The document provides information on map interpretation and contour maps. It begins with an introduction to maps and their basic elements such as title, key, scales, and contours. It then discusses contour patterns and how to interpret topographic features from contour maps such as ridges, valleys, slopes, and elevations. Contour maps represent elevations using contour lines that connect points of equal height. Contour maps are useful for engineering projects to determine optimal site selection and design of structures based on the topography.
This document provides an overview of cadastre and cadastral surveying. It discusses the basic components of a cadastre including cadastral surveying and mapping, land registration, and property taxation. It also describes parcel index maps, parcel maps, land tenure types, cadastral databases, the role of surveyors, procedures for cadastral surveying, and key aspects of boundaries and their demarcation. The overall purpose of cadastre and cadastral surveying is to precisely define and record land parcels to support land registration and ownership.
This document discusses various topics related to surveying including: the objectives and processes involved in surveying like decision making, fieldwork, data processing, mapping, and stakeout; different types of surveys like plane, geodetic, topographic, route, hydrographic, land, and military surveys; instruments used like theodolites, tacheometers, planes tables, and compasses; and concepts like bearings, meridians, and reducing bearings. The key aspects covered are the goal of producing maps, the consideration or disregard of earth's curvature depending on survey type, and classification based on area, instruments, or purpose.
This document describes how to read and interpret contour lines on topographic maps. It contains the following key points:
1. Contour lines connect points of equal elevation and are used to depict the shape and elevation changes of landforms.
2. Cross-sections can be drawn from contour lines to show the side profile of landforms between two points.
3. The spacing and shapes of contour lines indicate different landforms - closely spaced lines indicate steep slopes while widely spaced lines show gentle slopes. Common landforms like hills, valleys, ridges and plateaus each have distinguishing contour patterns.
4. Interpreting contour lines allows describing the overall landscape and calculating elevation changes across an area. The document provides instructions
Techniques of Land Surveying
The structure of Presentation:
Introduction to Land Survey
History of Land Survey
Types of Land Survey
Measurements
Modern Technologies
Geographical Information System
Photogrammetry
LiDAR
Airborne LiDAR
3D laser scanners
Surveying involves making measurements of natural and man-made features on earth and plotting them to form a map. It is used to establish boundaries, locations, and other purposes required by law such as property sales. There are different types of surveys including land, topographic, route, construction, hydrographic, mine, forestry, and control surveys that are carried out for various objectives like determining property boundaries, mapping topography, laying out infrastructure projects, and establishing reference points. Common land surveying techniques include measuring boundary lines, using triangulation, traversing, leveling, and using satellite positioning.
This document discusses contouring in surveying. It defines key terms like contour, contour line, and contour interval. It explains direct and indirect methods of contour surveying, including taking levels and establishing horizontal controls. It describes drawing contours and characteristics of contour maps, such as contours never intersecting except in cases of overhanging cliffs or vertical cliffs. Common contour line types are defined, like isobars and isotherms. Topographic maps and how to make a cross-section from a map are also summarized.
The document discusses different types of map projections used to represent the spherical Earth on a flat surface. It begins by explaining that map projections transform 3D global coordinates to 2D planar coordinates, which necessarily distorts properties like distances, angles, or areas. It then covers key projection categories (cylindrical, conic, azimuthal), their characteristic properties and examples. Specific projections discussed include Mercator, UTM, and polar stereographic. The document emphasizes that the appropriate projection depends on the map's intended use and which distortions are least important. It encourages map users to understand basic projection concepts.
This document provides an overview of cartography. It begins with definitions of cartography and discusses the importance and history of maps. The history section outlines some of the earliest maps from ancient civilizations like Babylonia, Egypt, and Greece. It also describes important contributions from figures like Ptolemy, including his world map and map projections. The document emphasizes that cartography has progressed from early conceptual maps to more accurate representations incorporating scientific principles.
This document provides an overview of cadastre and cadastral surveying. It discusses the basic components of a cadastre including cadastral surveying and mapping, land registration, and property taxation. It also describes parcel index maps, parcel maps, land tenure types, cadastral databases, the role of surveyors, procedures for cadastral surveying, and key aspects of boundaries and their demarcation. The overall purpose of cadastre and cadastral surveying is to precisely define and record land parcels to support land registration and ownership.
This document discusses various topics related to surveying including: the objectives and processes involved in surveying like decision making, fieldwork, data processing, mapping, and stakeout; different types of surveys like plane, geodetic, topographic, route, hydrographic, land, and military surveys; instruments used like theodolites, tacheometers, planes tables, and compasses; and concepts like bearings, meridians, and reducing bearings. The key aspects covered are the goal of producing maps, the consideration or disregard of earth's curvature depending on survey type, and classification based on area, instruments, or purpose.
This document describes how to read and interpret contour lines on topographic maps. It contains the following key points:
1. Contour lines connect points of equal elevation and are used to depict the shape and elevation changes of landforms.
2. Cross-sections can be drawn from contour lines to show the side profile of landforms between two points.
3. The spacing and shapes of contour lines indicate different landforms - closely spaced lines indicate steep slopes while widely spaced lines show gentle slopes. Common landforms like hills, valleys, ridges and plateaus each have distinguishing contour patterns.
4. Interpreting contour lines allows describing the overall landscape and calculating elevation changes across an area. The document provides instructions
Techniques of Land Surveying
The structure of Presentation:
Introduction to Land Survey
History of Land Survey
Types of Land Survey
Measurements
Modern Technologies
Geographical Information System
Photogrammetry
LiDAR
Airborne LiDAR
3D laser scanners
Surveying involves making measurements of natural and man-made features on earth and plotting them to form a map. It is used to establish boundaries, locations, and other purposes required by law such as property sales. There are different types of surveys including land, topographic, route, construction, hydrographic, mine, forestry, and control surveys that are carried out for various objectives like determining property boundaries, mapping topography, laying out infrastructure projects, and establishing reference points. Common land surveying techniques include measuring boundary lines, using triangulation, traversing, leveling, and using satellite positioning.
This document discusses contouring in surveying. It defines key terms like contour, contour line, and contour interval. It explains direct and indirect methods of contour surveying, including taking levels and establishing horizontal controls. It describes drawing contours and characteristics of contour maps, such as contours never intersecting except in cases of overhanging cliffs or vertical cliffs. Common contour line types are defined, like isobars and isotherms. Topographic maps and how to make a cross-section from a map are also summarized.
The document discusses different types of map projections used to represent the spherical Earth on a flat surface. It begins by explaining that map projections transform 3D global coordinates to 2D planar coordinates, which necessarily distorts properties like distances, angles, or areas. It then covers key projection categories (cylindrical, conic, azimuthal), their characteristic properties and examples. Specific projections discussed include Mercator, UTM, and polar stereographic. The document emphasizes that the appropriate projection depends on the map's intended use and which distortions are least important. It encourages map users to understand basic projection concepts.
This document provides an overview of cartography. It begins with definitions of cartography and discusses the importance and history of maps. The history section outlines some of the earliest maps from ancient civilizations like Babylonia, Egypt, and Greece. It also describes important contributions from figures like Ptolemy, including his world map and map projections. The document emphasizes that cartography has progressed from early conceptual maps to more accurate representations incorporating scientific principles.
Surveying is the science of determining the positions of points on or near the earth's surface. It involves decision making, fieldwork, data processing, mapping, and stakeout. The primary objectives of surveying are to prepare plans for estates, buildings, infrastructure, and to measure areas. Plane surveying considers the earth's surface flat over small areas, while geodetic surveying accounts for curvature over large areas. Distance is typically measured using tapes or chains, and errors are corrected for tape length and temperature.
This document provides an overview of land measurements and surveying. It discusses the different types of surveys like boundary surveys, topographic surveys, construction surveys, and as-built surveys. It also outlines the various agencies and jobs that use surveying, such as federal government agencies. Common surveying methods are also summarized, including measuring horizontal distances, angles, and elevation. The roles and responsibilities of land surveyors are briefly described.
Geodesy - Definition, Types, Uses and ApplicationsAhmed Nassar
literature review speaks about the geodesy and its relation to the figure of the earth. The definition of geodesy and the imagining of the earth's shape evolution throughout history, it passed at many important developments. We will discuss that geodesy almost interferes with all Geo- and Space sciences, by clarifying some of its uses and applications.
Map reading and interpretation involves examining maps to identify geographical information. Key skills for reading maps include identifying the title, scale, key, north direction, boundaries, and date. Drainage patterns like dendritic and trellised can be described from maps. Rock type is suggested by landforms, vegetation, and permeability. Climate can be inferred from latitude, altitude, water bodies, and vegetation. Topographical maps provide important geographical details about physical features, human activities, and population distribution.
Contours are lines on a map connecting points of equal elevation above sea level. They provide information about the height of land, difference in height between contours, slope of land determined by contour spacing, and shape of landforms. Contour patterns indicate slope - steep slopes have close contours, gentle slopes have widely spaced contours, and concave and convex slopes have variable spacing that reveals the landform shape.
The document discusses triangulation and trilateration methods for horizontal control surveys. It defines triangulation as establishing a network of triangles using measured baselines and calculated angles to determine station positions. Trilateration measures baseline lengths directly using EDM instead of calculating from angles. The document categorizes triangulation into three orders based on accuracy and describes ideal triangle configurations. It also discusses evaluating figure strength to maintain precision and defines well-conditioned triangles that minimize angular error effects.
Topographic maps show physical characteristics of an area such as rivers, streams, mountains, roads, and man-made structures. They use contour lines to indicate elevation and slope of the land, with closer lines representing a steeper slope. Elevation is noted in feet or meters and contour intervals show the change in elevation between lines. Features such as hills, summits, and depressions are represented symbolically.
1. Levelling is used to determine the relative heights of points and establish a common datum. It involves using a level instrument and staff to obtain precise elevation readings.
2. Key terms include benchmarks, backsight, foresight, and intermediate sight readings. Common level instruments are the dumpy level, tilting level, wye level, and automatic level.
3. Levelling methods include simple, differential, fly, check, profile, cross, and reciprocal levelling used for different applications such as construction works. Precise setup and focusing of the instrument are required before taking readings.
A map projection is a systematic transformation of the latitudes and longitudes of locations from the surface of a sphere or an ellipsoid into locations on a plane. Maps cannot be created without map projections.
This document discusses different types of map projections, including cylindrical, equal-area, and transverse Mercator projections. It provides properties and examples of each type. Specifically, it describes simple cylindrical projections as having straight parallels and meridians intersecting at right angles, with consistent distances but scale distortion away from the equator. It also outlines cylindrical equal-area projections as having decreasing distances between parallels but increasing distances between meridians, making it an equal-area projection but distorted at the poles. Finally, it explains transverse Mercator and Universal Transverse Mercator (UTM) projections use a 2D Cartesian system to locate positions on Earth within zones with minimal distortion.
Geography is defined as the science dealing with the location of living and non-living things on Earth and how they affect one another. The document discusses different types of maps used in geography including physical maps showing natural features, political maps showing governmental boundaries, regional maps showing distinct areas, climate maps showing temperature and precipitation patterns, and population maps showing where people live. An example political map of the United States is provided.
This document discusses aerial photogrammetry and provides definitions of key terms. It describes how aerial photographs are taken from aircraft and used to create topographic maps. The process involves establishing ground control points, planning flights and photography with proper overlap, interpreting photographs, using stereoscopes to view overlapping image pairs in 3D, and constructing maps through cartography. Precise measurement of ground coordinates is enabled through analyzing parallax differences between corresponding points in stereoscopic image pairs.
Contour lines on a topographical map represent imaginary lines connecting points of equal elevation above or below a datum. The vertical distance between contour lines is called the contour interval. Index contours are drawn with a heavier line every fifth contour to aid identification of elevations. Intermediate contours fall between index contours. Contour lines can be marked in the field using a homemade A-frame leveling device to identify points of equal height and indicate slope. The spacing of contour lines depends on the steepness of the slope, with closer lines used for steeper slopes to prevent soil erosion.
Clinometers are used in many professions to measure slopes and inclines. Geologists, surveyors, skiers, sailors, and cave surveyors use clinometers to measure heights, slopes, cloud heights, and map underground cave systems. City planners also use clinometers to ensure that roads and sidewalks do not exceed a 10% gradient, as steeper slopes can be dangerous and increase pollution from vehicles. The document provides examples of how clinometers are used in various fields and describes an activity where students measure hill gradients to determine if roads should be built.
The document discusses topographic maps and their numbering systems in India. It provides details on:
1) Topographic maps represent relief and also show features like transportation and settlements. They contain information like names, scales, and features.
2) In India, the Survey of India prepares topographic maps. Maps are part of two series - the India and Adjacent Country Series and the International Map of the World Series.
3) The India and Adjacent Country Series covers India in grids numbered from 40-92 that are divided into degree, quadrant, and special sheets at various scales with contour intervals.
Geodesy is the science of measuring and understanding the Earth. It involves determining the size, shape, and gravitational and magnetic fields of the Earth. Geodesy uses measurements from satellites, GPS, and fieldwork to model the Earth as a flattened ellipsoid with parameters like semi-major and semi-minor axes. An accurate mathematical model of the ellipsoid is needed for scientific and practical applications involving the representation of the Earth's shape.
This document outlines the steps to compute the closure, accuracy, and area of a traverse survey. It discusses key terms, sources of error, and a 9-step process to calculate closure, precision ratio, and area using the double meridian distance method. As an example, it works through the calculations for a 5-sided closed traverse, determining the closure is 0.49 feet, precision ratio is 1:4200, and total area is 6.126 acres.
This document discusses various tools used by geographers. It describes globes as 3D representations of Earth that are not portable, and maps as 2D graphic representations that are portable but distort Earth's surface. It also discusses satellites that provide geographic data, Geographic Information Systems that combine data layers, and GPS systems that transmit locations. The document outlines different types of maps and map projections, including planar, conical, cylindrical, and Mercator projections.
This document provides information about topographic maps, including:
1. Topographic maps show elevation, shape of the earth's surface using contour lines connecting points of equal elevation. Features like water, terrain, and human structures are shown through different colors and patterns.
2. Contour lines indicate elevation changes - closely spaced lines show steep slopes, widely spaced show gentle slopes. Contour lines never cross or branch. When crossing streams, they bend upstream. Closed contours indicate hills and depressions.
3. Topographic profiles show elevation changes along a line, often with vertical exaggeration to emphasize details. Gradient is the steepness of a slope. Constructing profiles involves connecting elevation points along a contour line slice
A map is a representation of all or part of the Earth drawn on a flat surface at a specific scale that uses symbols and colors to represent selected features of an area. Maps allow for accurate planning of journeys by showing landmarks, routes, and distances. There are different types of maps including general reference maps, thematic maps that illustrate a particular theme, and topographic maps that show landscape topography through contour lines.
Surveying is the science of determining the positions of points on or near the earth's surface. It involves decision making, fieldwork, data processing, mapping, and stakeout. The primary objectives of surveying are to prepare plans for estates, buildings, infrastructure, and to measure areas. Plane surveying considers the earth's surface flat over small areas, while geodetic surveying accounts for curvature over large areas. Distance is typically measured using tapes or chains, and errors are corrected for tape length and temperature.
This document provides an overview of land measurements and surveying. It discusses the different types of surveys like boundary surveys, topographic surveys, construction surveys, and as-built surveys. It also outlines the various agencies and jobs that use surveying, such as federal government agencies. Common surveying methods are also summarized, including measuring horizontal distances, angles, and elevation. The roles and responsibilities of land surveyors are briefly described.
Geodesy - Definition, Types, Uses and ApplicationsAhmed Nassar
literature review speaks about the geodesy and its relation to the figure of the earth. The definition of geodesy and the imagining of the earth's shape evolution throughout history, it passed at many important developments. We will discuss that geodesy almost interferes with all Geo- and Space sciences, by clarifying some of its uses and applications.
Map reading and interpretation involves examining maps to identify geographical information. Key skills for reading maps include identifying the title, scale, key, north direction, boundaries, and date. Drainage patterns like dendritic and trellised can be described from maps. Rock type is suggested by landforms, vegetation, and permeability. Climate can be inferred from latitude, altitude, water bodies, and vegetation. Topographical maps provide important geographical details about physical features, human activities, and population distribution.
Contours are lines on a map connecting points of equal elevation above sea level. They provide information about the height of land, difference in height between contours, slope of land determined by contour spacing, and shape of landforms. Contour patterns indicate slope - steep slopes have close contours, gentle slopes have widely spaced contours, and concave and convex slopes have variable spacing that reveals the landform shape.
The document discusses triangulation and trilateration methods for horizontal control surveys. It defines triangulation as establishing a network of triangles using measured baselines and calculated angles to determine station positions. Trilateration measures baseline lengths directly using EDM instead of calculating from angles. The document categorizes triangulation into three orders based on accuracy and describes ideal triangle configurations. It also discusses evaluating figure strength to maintain precision and defines well-conditioned triangles that minimize angular error effects.
Topographic maps show physical characteristics of an area such as rivers, streams, mountains, roads, and man-made structures. They use contour lines to indicate elevation and slope of the land, with closer lines representing a steeper slope. Elevation is noted in feet or meters and contour intervals show the change in elevation between lines. Features such as hills, summits, and depressions are represented symbolically.
1. Levelling is used to determine the relative heights of points and establish a common datum. It involves using a level instrument and staff to obtain precise elevation readings.
2. Key terms include benchmarks, backsight, foresight, and intermediate sight readings. Common level instruments are the dumpy level, tilting level, wye level, and automatic level.
3. Levelling methods include simple, differential, fly, check, profile, cross, and reciprocal levelling used for different applications such as construction works. Precise setup and focusing of the instrument are required before taking readings.
A map projection is a systematic transformation of the latitudes and longitudes of locations from the surface of a sphere or an ellipsoid into locations on a plane. Maps cannot be created without map projections.
This document discusses different types of map projections, including cylindrical, equal-area, and transverse Mercator projections. It provides properties and examples of each type. Specifically, it describes simple cylindrical projections as having straight parallels and meridians intersecting at right angles, with consistent distances but scale distortion away from the equator. It also outlines cylindrical equal-area projections as having decreasing distances between parallels but increasing distances between meridians, making it an equal-area projection but distorted at the poles. Finally, it explains transverse Mercator and Universal Transverse Mercator (UTM) projections use a 2D Cartesian system to locate positions on Earth within zones with minimal distortion.
Geography is defined as the science dealing with the location of living and non-living things on Earth and how they affect one another. The document discusses different types of maps used in geography including physical maps showing natural features, political maps showing governmental boundaries, regional maps showing distinct areas, climate maps showing temperature and precipitation patterns, and population maps showing where people live. An example political map of the United States is provided.
This document discusses aerial photogrammetry and provides definitions of key terms. It describes how aerial photographs are taken from aircraft and used to create topographic maps. The process involves establishing ground control points, planning flights and photography with proper overlap, interpreting photographs, using stereoscopes to view overlapping image pairs in 3D, and constructing maps through cartography. Precise measurement of ground coordinates is enabled through analyzing parallax differences between corresponding points in stereoscopic image pairs.
Contour lines on a topographical map represent imaginary lines connecting points of equal elevation above or below a datum. The vertical distance between contour lines is called the contour interval. Index contours are drawn with a heavier line every fifth contour to aid identification of elevations. Intermediate contours fall between index contours. Contour lines can be marked in the field using a homemade A-frame leveling device to identify points of equal height and indicate slope. The spacing of contour lines depends on the steepness of the slope, with closer lines used for steeper slopes to prevent soil erosion.
Clinometers are used in many professions to measure slopes and inclines. Geologists, surveyors, skiers, sailors, and cave surveyors use clinometers to measure heights, slopes, cloud heights, and map underground cave systems. City planners also use clinometers to ensure that roads and sidewalks do not exceed a 10% gradient, as steeper slopes can be dangerous and increase pollution from vehicles. The document provides examples of how clinometers are used in various fields and describes an activity where students measure hill gradients to determine if roads should be built.
The document discusses topographic maps and their numbering systems in India. It provides details on:
1) Topographic maps represent relief and also show features like transportation and settlements. They contain information like names, scales, and features.
2) In India, the Survey of India prepares topographic maps. Maps are part of two series - the India and Adjacent Country Series and the International Map of the World Series.
3) The India and Adjacent Country Series covers India in grids numbered from 40-92 that are divided into degree, quadrant, and special sheets at various scales with contour intervals.
Geodesy is the science of measuring and understanding the Earth. It involves determining the size, shape, and gravitational and magnetic fields of the Earth. Geodesy uses measurements from satellites, GPS, and fieldwork to model the Earth as a flattened ellipsoid with parameters like semi-major and semi-minor axes. An accurate mathematical model of the ellipsoid is needed for scientific and practical applications involving the representation of the Earth's shape.
This document outlines the steps to compute the closure, accuracy, and area of a traverse survey. It discusses key terms, sources of error, and a 9-step process to calculate closure, precision ratio, and area using the double meridian distance method. As an example, it works through the calculations for a 5-sided closed traverse, determining the closure is 0.49 feet, precision ratio is 1:4200, and total area is 6.126 acres.
This document discusses various tools used by geographers. It describes globes as 3D representations of Earth that are not portable, and maps as 2D graphic representations that are portable but distort Earth's surface. It also discusses satellites that provide geographic data, Geographic Information Systems that combine data layers, and GPS systems that transmit locations. The document outlines different types of maps and map projections, including planar, conical, cylindrical, and Mercator projections.
This document provides information about topographic maps, including:
1. Topographic maps show elevation, shape of the earth's surface using contour lines connecting points of equal elevation. Features like water, terrain, and human structures are shown through different colors and patterns.
2. Contour lines indicate elevation changes - closely spaced lines show steep slopes, widely spaced show gentle slopes. Contour lines never cross or branch. When crossing streams, they bend upstream. Closed contours indicate hills and depressions.
3. Topographic profiles show elevation changes along a line, often with vertical exaggeration to emphasize details. Gradient is the steepness of a slope. Constructing profiles involves connecting elevation points along a contour line slice
A map is a representation of all or part of the Earth drawn on a flat surface at a specific scale that uses symbols and colors to represent selected features of an area. Maps allow for accurate planning of journeys by showing landmarks, routes, and distances. There are different types of maps including general reference maps, thematic maps that illustrate a particular theme, and topographic maps that show landscape topography through contour lines.
A map is a representation of all or part of the Earth's surface drawn to scale. Maps use symbols and colors to represent features like landforms, roads, and vegetation. Contour lines connect points of equal elevation, allowing maps to depict three-dimensional terrain in two dimensions. Contour maps are useful for engineering projects to evaluate sites, trace grades, and calculate earthworks.
Topographic maps use contour lines to represent the three dimensional shape of the earth's surface. Contour lines connect points of equal elevation and the interval between lines indicates the steepness of slopes. A topographic profile can be created by slicing through a map along a line and plotting the elevations to show the shape and gradient of the terrain from the side.
This document provides information about topographic maps, including:
1. It defines topographic maps and lists their key features such as elevation, shape of land, water features, and human structures.
2. It explains how contour lines represent elevation and slope on topographic maps, with more closely spaced lines indicating steeper slopes and widely spaced lines indicating gentler slopes.
3. It provides instructions for constructing topographic profiles from contour map data and examples of profiles of different landforms.
This document provides an overview of maps and map elements. It discusses the different types of maps including general purpose maps, thematic maps, and topographic maps. It describes the basic elements of maps such as titles, scales, legends, and directions. Contour lines and how to read elevation and slope from topographic maps are explained in detail. The purpose and uses of contour maps for engineering projects are also summarized.
This document provides an introduction to maps and map elements. It discusses the basic components of maps including titles, scales, legends, and directions. It also describes different types of maps such as general reference maps, thematic maps, and topographic maps. Topographic maps are explained in detail, including how they use contour lines to show elevation changes and terrain features. The key elements of contour maps like contour intervals and index contours are defined. Finally, the document outlines the purposes and uses of contour maps for engineering projects.
This document provides an introduction to maps and map elements. It discusses the basic components of maps including titles, scales, legends, and directions. It also describes different map types such as general reference maps, thematic maps, and topographic maps. Topographic maps are explained in detail, including how they use contour lines to show elevation changes and terrain features. The key elements of contour maps like contour intervals and index contours are defined. Finally, the document outlines the purposes and uses of contour maps for engineering projects.
This document provides an overview of maps and map elements. It discusses the different types of maps including general purpose maps, thematic maps, and topographic maps. It describes the basic elements of maps such as titles, scales, legends, and directions. Contour lines and how to read elevation and slope from topographic maps are explained in detail. The purpose and uses of contour maps for engineering projects are also summarized.
Topographic maps use contour lines to represent the shape and elevation of land. Contour lines connect points of equal elevation and never touch or cross. Closely spaced lines indicate steep slopes, while widely spaced lines show gentle slopes. A contour interval is the elevation difference between lines. Topographic maps also use colors, symbols and labels to depict features like water, vegetation and man-made objects. Benchmarks provide exact elevation references and are marked on maps with their altitude in feet.
This document discusses key geographical skills and investigations, including topographical map reading skills, geographical data techniques, and geographical investigations. It covers topics such as reading topographical maps, interpreting scales, measuring distances, describing relief features, identifying landforms, calculating gradients, interpreting map symbols, describing patterns of vegetation and land use, and explaining relationships between relief and land use. It also discusses using photographs, satellite images, and different types of graphs to depict and analyze geographical data.
Topographic maps show elevation and surface features of land using contour lines to connect points of equal height. Contour lines never cross and indicate slope - closely spaced lines mean steep slopes while lines far apart indicate flat land. Topographic maps are used to understand the shape and elevation of the land.
This chapter discusses key geographical skills like map reading, interpreting data representations, and conducting fieldwork investigations. It covers topics such as reading grid references, compass directions, scales, measuring distances, interpreting reliefs and landforms on maps, and analyzing photographs and satellite images. Various types of graphs like line graphs, bar graphs, pie charts, and climographs are introduced to represent geographical data. The three phases of fieldwork - pre-fieldwork, during fieldwork, and post-fieldwork - are also outlined.
Contour lines on a map represent imaginary lines connecting points of equal elevation. The contour interval is the vertical distance between contour lines, and depends on factors like the terrain and map scale. Contour maps depict the shape of the land through the spacing and patterns of contour lines. Closely-spaced lines indicate steep slopes, while widely-spaced lines show flatter areas. Contour maps are useful for engineering projects to determine suitable sites, locate infrastructure alignments, and estimate earthworks and reservoir capacities.
Topographic maps use contour lines to represent elevation and slope of land. Contour lines connect points of equal elevation and never cross. Closer lines indicate steeper slopes while widely spaced lines show more gentle slopes. Index contours are bold lines labeled with the elevation. A benchmark is a point of known exact elevation marked as B.M. on maps. Map scale relates distances on a map to actual distances on land and can be ratio, graphical, or verbal.
This document provides an introduction to map interpretation and sketching for level 1 students. It covers basic map elements like titles, scales, legends, and contours. It describes different map types such as topographic maps and thematic maps. Topographic maps show elevation using contour lines, which represent points of equal height. The spacing of contour lines indicates steep or gentle slopes. Common features like valleys, ridges, hills and depressions are identified by the shape and direction of contour lines. The document is intended to teach students how to interpret maps and understand topographic information.
This document provides an overview of topographic maps, including what they are, how to read them, and what features they represent. Topographic maps use contour lines to show elevation and relief of landforms. Contour lines connect points of equal elevation, and the interval between lines indicates changes in height. Slope, streams, hills, and other terrain features are represented through the spacing and shapes of contour lines. Topographic maps also use colors, labels, and other symbols to depict cultural features, vegetation, and other map elements.
The document provides information on key concepts related to maps and map reading, including:
1) Maps are graphical representations of physical and cultural features on Earth's surface, with symbols used to denote features. Scale allows large areas to be shown on small maps and is expressed verbally, as a ratio, or with a bar scale.
2) Grid references use a system of eastings and northings to precisely locate features on maps divided into grids. Contour lines and spot heights indicate land elevation and relief. Hachures and shading are also used to represent relief.
3) Maps use colors to represent different features - green for forests, blue for water, etc. Settlement patterns, drainage patterns, transportation
An engineering drawing is a technical drawing that clearly defines and communicates a design. It allows for collaboration in design, procurement, manufacturing, quality control, and other areas. The document then discusses various topics related to engineering drawings including types of lines, dimensioning, lettering, and scales.
An engineering drawing is a technical drawing that clearly defines and communicates a design. It is used for collaboration, procurement, manufacturing, and quality control. The document discusses the role of graphics in visualization, communication, and documentation. It provides examples of engineering drawing applications in construction, manufacturing, and ships. The document also covers drawing instruments, types of lines, dimensioning, lettering, and scales used in engineering drawings.
Contour maps use contour lines to represent three-dimensional terrain in two dimensions. Contour lines connect points of equal elevation and their spacing indicates the steepness of slopes - lines closer together mean steeper terrain. Contour maps provide more detailed topographical information than other map types by depicting the shape and gradient of land and can be used to infer elevation changes even when numerical spot heights are not provided.
This document provides an introduction to reading and interpreting maps for geology and geography students. It covers key map elements like the title, scale, legend, and contours. Contours show elevations and can reveal landforms. Cross-sections help visualize terrain in 2D. The document teaches how to identify features like valleys, ridges, and hills based on contour patterns and recommends drawing cross-sections to confirm interpretations. It emphasizes that maps are a projection of 3D space onto a 2D surface.
This document provides an overview of basic water supply system operations, including sources of drinking water, advantages and disadvantages of surface water and groundwater sources, and treatment processes for both. It discusses intake processes like racks and screens, mixing, coagulation and flocculation, sedimentation, and filtration. Disinfection methods like chlorine, ultraviolet light, and ozone are also covered. The document concludes with descriptions of distribution system facilities such as pumps, storage, transmission mains, valves and hydrants.
The document discusses network models and compares the OSI model and TCP/IP model. It provides details on the layers of the OSI model including the 7 layers from physical to application layer. It describes the functions of each layer such as physical dealing with raw bit transmission, data link framing bits into frames, network routing packets, transport ensuring reliable data delivery, session controlling connections, presentation translating between systems, and application providing user interfaces. It also summarizes the similarities and differences between the OSI and TCP/IP models.
Sewer systems are piped networks that transport wastewater from source points like households to treatment facilities. There are several types of sewer systems depending on factors like topography and amount of wastewater. Conventional sewer systems combine wastewater and stormwater in large underground pipes while separate sewer systems transport them separately. Sewer systems require substantial resources to build and maintain but can provide sanitation convenience at scale.
1) The document discusses IP addressing and the different types of addresses used - physical, logical (IP), port, and specific addresses.
2) It describes the four classes of IP addresses - Class A, B, C, and D - and the network and host portions of each. Class A is for large networks, Class B for medium, and Class C for small networks.
3) Certain IP addresses are reserved and cannot be assigned to hosts, including network addresses, broadcast addresses, and the loopback address of 127.0.0.1. Proper allocation of addresses is important to avoid conflicts.
This document provides teaching and learning resources on geometrical constructions. It defines various 2D shapes like polygons, regular polygons, and irregular polygons. It lists the names of polygons according to the number of sides. It also describes 3D solids like cubes, cylinders, prisms, and pyramids. For cubes and cylinders, it provides the formulas to calculate their volume and surface area. It includes examples and diagrams of different types of prisms and pyramids. The resources were prepared by a group consisting of Vanesri Kasi, Yamuna Sandaran, and Tinagaran Magesparan for computer construction.
The document discusses various techniques for drawing geometric shapes and constructions. It covers topics such as drawing parallel and perpendicular lines, bisecting lines and angles, dividing lines into multiple sections, finding the center of arcs and circles, inscribing and circumscribing circles in triangles, drawing regular polygons like hexagons, constructing ellipses, and defining curves like cycloids, epicycloids, involutes, and Archimedean spirals. The document provides step-by-step instructions for performing each geometric construction or drawing.
Topographic maps provide three-dimensional information about natural and man-made features of landscapes using contour lines to show elevations. Contour lines connect points of equal height, with steeper slopes having lines closer together. Topographic maps depict mountains, valleys, plains, rivers, lakes, roads, boundaries, buildings and other structures, and are used for purposes like engineering, planning, military operations, and recreation. Satellite images can be matched to topographic maps using the shapes and elevations of the landscapes.
1) The document provides information on basic geometric elements such as points, lines, angles, and their construction. It also covers plane figures like triangles, quadrilaterals, polygons and circles.
2) Solid geometric shapes such as prisms, pyramids, cylinders and cones are described along with their geometric construction.
3) The document also summarizes methods for constructing common curves like ellipses, parabolas, hyperbolas and their geometric properties.
Engineering drawings are a graphical language used to communicate technical design information between engineers. There are different projection methods for engineering drawings, including orthographic projection and axonometric projection. Orthographic projection uses parallel lines of sight to produce accurate multi-view drawings that show the true shape and size of an object through multiple two-dimensional views. Axonometric projection shows an object's three dimensions in a single view, making it easier to understand but introducing distortions from the true shape and size. Understanding engineering graphics and different projection methods is essential for effective technical communication.
1. Contours are imaginary lines on a map that connect points of equal elevation. Contour maps show these lines, representing the topography of the land.
2. There are two main methods for creating contour maps - direct and indirect. The direct method involves precisely surveying points along contour lines in the field. The indirect method takes spot elevations across an area and interpolates the contour lines.
3. Common indirect techniques include surveying on a grid, along cross-sections, or using a tacheometer to measure multiple points from instrument stations. Spot elevations are plotted and contour lines drawn in between based on the terrain. The indirect method is faster but less precise than the direct method.
Contour lines on a topographical map represent imaginary lines connecting points of equal elevation above or below a datum. The vertical distance between contour lines is called the contour interval. Index contours are drawn with a heavier line every fifth contour to aid identification of elevations. Intermediate contours fall between index contours. Contour lines can be marked in the field using a homemade A-frame leveling device to identify points of equal height and indicate slope. The spacing of contour lines depends on the steepness of the slope, with closer lines used for steeper slopes to prevent soil erosion.
This document discusses different types of maps and their purposes. It explains that globes show the Earth as seen from space, with continents and oceans, while maps show the Earth on a flat surface so they can be carried. Maps contain elements like titles, legends, compass roses and scales. The document describes political, physical and other types of maps, and how grid systems of latitude and longitude allow precise locations to be identified using coordinates.
Contour maps use contour lines to connect points of equal elevation and represent the topography of a land area. Contour lines become closer together in steep slopes and farther apart in gradual slopes. They form a V pattern along valleys. Index contours are used to label elevations at regular intervals. The distance between contours is called the contour interval. Contour maps can show hills, depressions, and other geological features through patterns of concentric closed contours. They are generated from elevation points measured in the field.
Contour lines are lines connecting points of equal elevation on a map. They allow elevation information to be represented visually. Key characteristics of contour lines include:
- Contour lines are continuous and either close upon themselves or extend from the map boundary.
- They are generally parallel unless passing through cliffs or overhangs.
- Valleys are indicated by V-shaped lines pointing uphill and ridges by U-shaped lines pointing downhill.
- Closely spaced lines indicate steep slopes while widely spaced lines indicate gentle slopes.
- Closed contours indicate hills or depressions.
Proper interpolation between surveyed elevation points is required to accurately draw contour lines. This involves calculating proportional distances based on the elevation difference between points
Topographic maps provide elevation information about land in addition to location details. Contour lines connect points of equal elevation, with closer lines indicating steeper slopes. Topographic maps are useful for activities like hiking, camping, and search and rescue. They show elevation, slopes, depressions, benchmarks, and other terrain features using contour lines, hachures, and map scales.
This document provides an overview of maps and mapmaking. It discusses what maps are, the different types of maps, important map elements, and the basic mapmaking process. The key stages in making a map include choosing a map projection and reference system, collecting data, and using software tools for tasks like creating points, lines and polygons. The document also contrasts traditional manual mapmaking techniques with modern GIS-based mapping, noting that GIS allows for easier data retrieval, analysis and map production. It concludes by discussing the future role of GIS in mapping.
GraphSummit Singapore | The Future of Agility: Supercharging Digital Transfor...Neo4j
Leonard Jayamohan, Partner & Generative AI Lead, Deloitte
This keynote will reveal how Deloitte leverages Neo4j’s graph power for groundbreaking digital twin solutions, achieving a staggering 100x performance boost. Discover the essential role knowledge graphs play in successful generative AI implementations. Plus, get an exclusive look at an innovative Neo4j + Generative AI solution Deloitte is developing in-house.
TrustArc Webinar - 2024 Global Privacy SurveyTrustArc
How does your privacy program stack up against your peers? What challenges are privacy teams tackling and prioritizing in 2024?
In the fifth annual Global Privacy Benchmarks Survey, we asked over 1,800 global privacy professionals and business executives to share their perspectives on the current state of privacy inside and outside of their organizations. This year’s report focused on emerging areas of importance for privacy and compliance professionals, including considerations and implications of Artificial Intelligence (AI) technologies, building brand trust, and different approaches for achieving higher privacy competence scores.
See how organizational priorities and strategic approaches to data security and privacy are evolving around the globe.
This webinar will review:
- The top 10 privacy insights from the fifth annual Global Privacy Benchmarks Survey
- The top challenges for privacy leaders, practitioners, and organizations in 2024
- Key themes to consider in developing and maintaining your privacy program
Programming Foundation Models with DSPy - Meetup SlidesZilliz
Prompting language models is hard, while programming language models is easy. In this talk, I will discuss the state-of-the-art framework DSPy for programming foundation models with its powerful optimizers and runtime constraint system.
How to Get CNIC Information System with Paksim Ga.pptxdanishmna97
Pakdata Cf is a groundbreaking system designed to streamline and facilitate access to CNIC information. This innovative platform leverages advanced technology to provide users with efficient and secure access to their CNIC details.
Unlock the Future of Search with MongoDB Atlas_ Vector Search Unleashed.pdfMalak Abu Hammad
Discover how MongoDB Atlas and vector search technology can revolutionize your application's search capabilities. This comprehensive presentation covers:
* What is Vector Search?
* Importance and benefits of vector search
* Practical use cases across various industries
* Step-by-step implementation guide
* Live demos with code snippets
* Enhancing LLM capabilities with vector search
* Best practices and optimization strategies
Perfect for developers, AI enthusiasts, and tech leaders. Learn how to leverage MongoDB Atlas to deliver highly relevant, context-aware search results, transforming your data retrieval process. Stay ahead in tech innovation and maximize the potential of your applications.
#MongoDB #VectorSearch #AI #SemanticSearch #TechInnovation #DataScience #LLM #MachineLearning #SearchTechnology
Sudheer Mechineni, Head of Application Frameworks, Standard Chartered Bank
Discover how Standard Chartered Bank harnessed the power of Neo4j to transform complex data access challenges into a dynamic, scalable graph database solution. This keynote will cover their journey from initial adoption to deploying a fully automated, enterprise-grade causal cluster, highlighting key strategies for modelling organisational changes and ensuring robust disaster recovery. Learn how these innovations have not only enhanced Standard Chartered Bank’s data infrastructure but also positioned them as pioneers in the banking sector’s adoption of graph technology.
GraphSummit Singapore | The Art of the Possible with Graph - Q2 2024Neo4j
Neha Bajwa, Vice President of Product Marketing, Neo4j
Join us as we explore breakthrough innovations enabled by interconnected data and AI. Discover firsthand how organizations use relationships in data to uncover contextual insights and solve our most pressing challenges – from optimizing supply chains, detecting fraud, and improving customer experiences to accelerating drug discoveries.
Threats to mobile devices are more prevalent and increasing in scope and complexity. Users of mobile devices desire to take full advantage of the features
available on those devices, but many of the features provide convenience and capability but sacrifice security. This best practices guide outlines steps the users can take to better protect personal devices and information.
In his public lecture, Christian Timmerer provides insights into the fascinating history of video streaming, starting from its humble beginnings before YouTube to the groundbreaking technologies that now dominate platforms like Netflix and ORF ON. Timmerer also presents provocative contributions of his own that have significantly influenced the industry. He concludes by looking at future challenges and invites the audience to join in a discussion.
Removing Uninteresting Bytes in Software FuzzingAftab Hussain
Imagine a world where software fuzzing, the process of mutating bytes in test seeds to uncover hidden and erroneous program behaviors, becomes faster and more effective. A lot depends on the initial seeds, which can significantly dictate the trajectory of a fuzzing campaign, particularly in terms of how long it takes to uncover interesting behaviour in your code. We introduce DIAR, a technique designed to speedup fuzzing campaigns by pinpointing and eliminating those uninteresting bytes in the seeds. Picture this: instead of wasting valuable resources on meaningless mutations in large, bloated seeds, DIAR removes the unnecessary bytes, streamlining the entire process.
In this work, we equipped AFL, a popular fuzzer, with DIAR and examined two critical Linux libraries -- Libxml's xmllint, a tool for parsing xml documents, and Binutil's readelf, an essential debugging and security analysis command-line tool used to display detailed information about ELF (Executable and Linkable Format). Our preliminary results show that AFL+DIAR does not only discover new paths more quickly but also achieves higher coverage overall. This work thus showcases how starting with lean and optimized seeds can lead to faster, more comprehensive fuzzing campaigns -- and DIAR helps you find such seeds.
- These are slides of the talk given at IEEE International Conference on Software Testing Verification and Validation Workshop, ICSTW 2022.
Full-RAG: A modern architecture for hyper-personalizationZilliz
Mike Del Balso, CEO & Co-Founder at Tecton, presents "Full RAG," a novel approach to AI recommendation systems, aiming to push beyond the limitations of traditional models through a deep integration of contextual insights and real-time data, leveraging the Retrieval-Augmented Generation architecture. This talk will outline Full RAG's potential to significantly enhance personalization, address engineering challenges such as data management and model training, and introduce data enrichment with reranking as a key solution. Attendees will gain crucial insights into the importance of hyperpersonalization in AI, the capabilities of Full RAG for advanced personalization, and strategies for managing complex data integrations for deploying cutting-edge AI solutions.
Why You Should Replace Windows 11 with Nitrux Linux 3.5.0 for enhanced perfor...SOFTTECHHUB
The choice of an operating system plays a pivotal role in shaping our computing experience. For decades, Microsoft's Windows has dominated the market, offering a familiar and widely adopted platform for personal and professional use. However, as technological advancements continue to push the boundaries of innovation, alternative operating systems have emerged, challenging the status quo and offering users a fresh perspective on computing.
One such alternative that has garnered significant attention and acclaim is Nitrux Linux 3.5.0, a sleek, powerful, and user-friendly Linux distribution that promises to redefine the way we interact with our devices. With its focus on performance, security, and customization, Nitrux Linux presents a compelling case for those seeking to break free from the constraints of proprietary software and embrace the freedom and flexibility of open-source computing.
In the rapidly evolving landscape of technologies, XML continues to play a vital role in structuring, storing, and transporting data across diverse systems. The recent advancements in artificial intelligence (AI) present new methodologies for enhancing XML development workflows, introducing efficiency, automation, and intelligent capabilities. This presentation will outline the scope and perspective of utilizing AI in XML development. The potential benefits and the possible pitfalls will be highlighted, providing a balanced view of the subject.
We will explore the capabilities of AI in understanding XML markup languages and autonomously creating structured XML content. Additionally, we will examine the capacity of AI to enrich plain text with appropriate XML markup. Practical examples and methodological guidelines will be provided to elucidate how AI can be effectively prompted to interpret and generate accurate XML markup.
Further emphasis will be placed on the role of AI in developing XSLT, or schemas such as XSD and Schematron. We will address the techniques and strategies adopted to create prompts for generating code, explaining code, or refactoring the code, and the results achieved.
The discussion will extend to how AI can be used to transform XML content. In particular, the focus will be on the use of AI XPath extension functions in XSLT, Schematron, Schematron Quick Fixes, or for XML content refactoring.
The presentation aims to deliver a comprehensive overview of AI usage in XML development, providing attendees with the necessary knowledge to make informed decisions. Whether you’re at the early stages of adopting AI or considering integrating it in advanced XML development, this presentation will cover all levels of expertise.
By highlighting the potential advantages and challenges of integrating AI with XML development tools and languages, the presentation seeks to inspire thoughtful conversation around the future of XML development. We’ll not only delve into the technical aspects of AI-powered XML development but also discuss practical implications and possible future directions.
Essentials of Automations: The Art of Triggers and Actions in FMESafe Software
In this second installment of our Essentials of Automations webinar series, we’ll explore the landscape of triggers and actions, guiding you through the nuances of authoring and adapting workspaces for seamless automations. Gain an understanding of the full spectrum of triggers and actions available in FME, empowering you to enhance your workspaces for efficient automation.
We’ll kick things off by showcasing the most commonly used event-based triggers, introducing you to various automation workflows like manual triggers, schedules, directory watchers, and more. Plus, see how these elements play out in real scenarios.
Whether you’re tweaking your current setup or building from the ground up, this session will arm you with the tools and insights needed to transform your FME usage into a powerhouse of productivity. Join us to discover effective strategies that simplify complex processes, enhancing your productivity and transforming your data management practices with FME. Let’s turn complexity into clarity and make your workspaces work wonders!
Presentation of the OECD Artificial Intelligence Review of Germany
Maps-and-map-interpretation.docx
1. Map interpretation
Contents
• Part 1 - Introduction to maps
• Title
• Key (sometimes called legend or explanation)
• Scales
• Contours
• Part 2 – Map interpretation
• Contour patterns
2. Part 1 - Introduction to maps
• A map is a representation of all or part of the Earth
drawn on a flat surface at a specific scale.
• Maps use a variety of symbols and colours to represent
selected features of an area.
3. TYPES OF MAPS
• General purpose maps (reference maps, )
• show both natural and human-made features such as
coastlines, lakes, rivers, boundaries, settlements, roads,
rail lines, and others.
• Thematic maps, (special-purpose maps, )
illustrate the geographical distribution of a particular theme or
phenomenon. Landforms, aspects of climate, vegetation and
soil types, demographics, industry, manufacturing, and natural
resources are examples of common thematic maps.
• topographic maps.
• As the term suggests, these maps show the topography or
surface features of the landscape through the use of
contour lines.
5. The upper left side map is
political map for Europe
but the lower right-side map
is showing physical appearance
of Europe continent
6. • all maps share common properties or map basics that provide
information to assist the reader in studying and interpreting
the maps. and they are called map elements as listed below.
Map elements
• a title,
• scale,
• legend,
• date of publication,
• direction,
• information about the map projection. etc
7. Direction: Direction tells you which way to hold the map.
By convention, most maps are made with their top portion
directed at North. The North direction is generally indicated by
an arrow in the maps
Legend is a guide which lists symbols and colours used on a map
to represent different geographic features. Legend helps to identify
what symbols and colours represent
Scale: can be defined as the ratio of the distance between two
points on the map and the same two points on the Earth’s surface.
8.
9. topographic maps.
As the term suggests, these maps show the topography or
surface features of the landscape through the use of contour
lines.
Contours are lines on a map that join places of equal
elevation above sea level.
This three-dimensional effect allows for detailed study of
landscape and drainage features.
Topographic maps are usually of a large scale and show
many of the features of general-purpose maps in considerable
detail.
11. 1 km
Topographic profile
topographic profile is a diagram that shows the
change in elevation of the land surface along any
given line (an area “looked from the side”).
12. How to Make a Topographic Profile
This represents a very simple topographic map of a hill. The hill is steep on the left side (the
contour lines are very close together) and has a gentle slope on the right side. The numbers
represent the elevation of the contour lines. (*)
What would the hill look like if you were to slice it from left to right? (*)
13. 1
0
0
Thus you have a topographic profile. This is what the hill would look like if you were to cut it
along the profile line and look at it from the side. (*)
300
500 feet
400 feet
300 feet
200 feet
100 feet
Normally, the Earth’s surface is not this blocky. In a topographic profile a line is drawn from these
points (red dots) producing a smooth transition. (*)
200
4
0
0
14. Contour lines
•Contour An imaginary line on the ground surface joining the points
of equal elevation is known as contour.
•It facilitates depiction of the relief of terrain in a two-dimensional
plan or map.
•In other words, contour is a line in which the ground surface is
intersected by a level surface obtained by joining points of equal
elevation. This line on the map represents a contour and is called
contour line.
•Contouring is the science of representing the verticaldimension of
the terrain on a two-dimensional map.
16. Prepared by Eng Shuaib [Type here]
• Contour Map
• a map showing contour lines is known as Contour map.
• A contour map gives an idea of the altitudes of the surface
features as well as their relative positions in plan serves the
purpose of both, a planand a section.
17. Prepared by Eng Shuaib [Type here]
Basicelementsofcontourmaps:
index Contour Line is a bolded Contour lines with elevation numbers
above the sea level
Contour Interval (CI) – It is the vertical distance between any two
consecutive contours.
This interval depends upon
(i) the nature of the ground (i.e. whether flat or sleep).
(ii) the scale of the map
(iii) the purpose of the survey.
Horizontal equivalent (he) Horizontal equivalent is the horizontal
distance between two consecutive contour lines measured tothe scale of
the map.
Gradient - The steepness of a slope as measured in degrees,
percentage, or as a distance ratio (rise/run).
18. Prepared by Eng Shuaib [Type here]
lines
The difference in
elevation between
the two index
contours (800 - 700)
is 100. We cross
five lines as we go
from the 700 line to
the 800 line (NOTE:
We count the lines
between the index
contours, then ADD
one. In this case,
we have 4 lines + 1
= 5). Therefore is
we divide the
elevation
difference
(100) by the
numberof lines (5)
we will get the
contour interval. In
this
case it is 20.
19. Prepared by Eng Shuaib [Type here]
100
1400
5
35
200
4400
10
30
10
30
20
0
21. Prepared by Eng Shuaib [Type here]
General Features of Contour Lines
Topographic Maps can show:
elevation:
Contour lines connect
points of equal elevation.
Topographic Maps can show:
if the land is steep or gentle
Steep slopes are shown
by closely spaced contour
lines.
Gentle slopes are shown
by widely spaced contour
lines.
Contour lines do not
intersect, branch or cross.
22. Prepared by Eng Shuaib [Type here]
Topographic Maps can identify whether it is a ridge or a valley,
rivers and streams flow directions:
Contour line cross ridge line at right angles. If the higher values are inside
the bend or loop in the contour, it indicates a ridge.
Rule 9 - Contour lines create V (or U) patterns when they cross a ridge. The tip or blunt end of the V or U at a ridge ALWAYS points
downhill.
Contour lines form V’s that point upstream when they cross a stream. ■ It is important to remember that they point in the opposite direction as the flow of water.
The spur is the higher lying ground adjacent to the valley. • Spurs are identified as follows: – The rounded “Ushaped” contours point towards lower ground. – Spurs will
not have rivers present
• A valley may be identified in the following manner: – The sharp “V-shaped” contours point towards higher ground. – A valley usually has some form of river or stream
present.
23. Prepared by Eng Shuaib [Type here]
8) Contour line cross ridge or valley line at right angles.
24. Prepared by Eng Shuaib [Type here]
If the higher values are outside the bend it represents a valley.
When contour lines cross
streams they bend in upstream;
that means, the contour line
forms a 'V or U-shaped' with
the apex at the intersection
with the stream, and pointing
in an upstream direction.
25. Prepared by Eng Shuaib [Type here]
v) Contour line cross ridge or valley line atright angles.
If the higher values
are inside the bend or loop in the contour,
itindicates a Ridge.
Contour line cross ridge or valley line at right angles. If the higher values are inside the bend or
loop in the contour it indicates a ridge. 8) Contour line cross ridge or valley line at right angles.
If the higher values are outside the bend it represents a valley.
31. Prepared by Eng Shuaib [Type here]
index Contour Line : is a bolded Contour lines with elevation
numbers above the sea level
Contour Interval (CI) – It is the vertical distance between any
twoconsecutive contours.
This interval depends upon
(iv) the nature of the ground (i.e. whether flat or sleep).
(v) the scale of the map
(vi) the purpose of the survey.
Horizontal equivalent (he) Horizontal equivalent is the
horizontal distance between two consecutive contour lines
measured tothe scale of the map.
33. Prepared by Eng Shuaib [Type here]
uniformly spaced.
iv) A plane surface when they are straight, parallel
andequally spaced.
CHARACTERISTICS OF CONTOURS
i) All points in a contour line have the same elevation.
ii) Flat ground is indicated where the contours are
widelyseparated and steep-slope where they run close
together.
iii) Auniform slope is indicated when the contour lines are
36. Prepared by Eng Shuaib [Type here]
CHARACTERISTICS OF CONTOURS
i) A series of closed
contour lines on the 80
map represent a hill 75
, if the higher values 70
are inside 65
60
HILL
60
65
70
75
80
37. Prepared by Eng Shuaib [Type here]
CHARACTERISTICS OF CONTOURS
80
vii) A
series of 75
closed contour 70
lines on the map 65
indicate a
depression if the 60
higher values
areoutside
38. Prepared by Eng Shuaib [Type here]
60
65
70
75
80
A DEPRESSION
39. Prepared by Eng Shuaib [Type here]
CHARACTERISTICS OF CONTOURS
viii) Contour line cross ridge or valley line at
right angles. If the higher values
100
90
80
are inside the bend orloop in the contour, itindicates a
Ridge.
70
60
50
RIDGE LINE
40. Prepared by Eng Shuaib [Type here]
CHARACTERISTICS OF CONTOURS
vii) Contour line cross ridge or valley line at
right angles.
If the higher values are
outside the bend, it
100 represents aValley
90
80
70
60
50
VALLEY LINE
41. Prepared by Eng Shuaib [Type here]
CHARACTERISTICS OF CONTOURS
viii). Contours cannot end anywhere but close
on themselves either within or outside the
limits
of the map.
42. Prepared by Eng Shuaib [Type here]
CHARACTERISTICS OF CONTOURS
ix).
Contour lines cannot 40
merge or cross one 30
another on map 20
exceptin the case of
an overhanging cliff.
40 30 20 10
OVERHANGING CLIFF
10
43. Prepared by Eng Shuaib [Type here]
CHARACTERISTICS OF CONTOURS
x)Contour lines never run
into one another except
in the case of vertical cliff.
In this case, several Contours
coincide and the horizontal
equivalent becomes zero.
OVERHANGING CLIFF
VERTIC
CLIFF
10 20 30 40
50
30
50
40
20
10
44. Prepared by Eng Shuaib [Type here]
CHARACTERISTICS OF CONTOURS
XI) Depressions between
summits is called a saddle.
Itis represented by four sets
of contours as shown. It
represents a dip in a ridge
or
the junction of two ridges. 70
And in the case of a mountain
80 range, i t takes the form of
a 90
pass.
SADDLE 70
80
90
90
100
110
Line passing through the saddles and summits gives watershed line.
23
45. Prepared by Eng Shuaib [Type here]
200
150
100
50
Think where is the steepest slope on this island?
46. Prepared by Eng Shuaib [Type here]
Steepest slope –
contour lines are
closest together
Sparrow
point 227
.76
150
200
100
50
Sometimes spot heights can be shown as a dot with a noteof the
height of that particular place.
A trigonometrical point (or trig point) shows the highest point in
an area (in meters and is shown as a blue triangle
47. Prepared by Eng Shuaib [Type here]
the shape and pattern of the contour lines
52. Prepared by Eng Shuaib [Type here]
PURPOSE (uses) OF CONTOURING/CONTOUR MAP
Contour survey is carried out at the starting of any
engineering project such as a road, a railway, a canal,
adam, a building etc.
i) contour maps are prepared in order to select the
mosteconomical or suitable site.
ii) It helps to locate the alignment of a canal so that itshould follow a ridge line.
iii) It helps to mark the alignment of roads and railways so
that the quantity of earthwork both in cutting and
fillingshould be minimum.
53. Prepared by Eng Shuaib [Type here]
iv) It helps for getting information about the groundwhether it is flat, undulating or mountainous.
v) It helps to find the capacity of a reservoir and
volumeof earthwork especially in a mountainous
region.
vi) It helps to trace out the given grade of a particularroute.
vii) It helps to locate the physical features of the
groundsuch as a pond depression, hill, steep or small
slopes.
(Undulating – rising & falling
57. Prepared by Eng Shuaib [Type here]
Contours
• Contours are lines joining points of equal value.
This value on topographic maps is height (or
elevation/altitude) above mean sea level (MSL)
• Each successive contour represents an increase or
decrease in constant value. Often every 5th
contour
will be in bold to help identification
• Contours are normally associated with changes in
height, but they can represent any parameter
(e.g. thickness, pressure, rainfall). They can also
58. Prepared by Eng Shuaib [Type here]
be called iso-lines (e.g. isopachs, isobars, isohyets)
59. Prepared by Eng Shuaib [Type here]
Contours show the distribution and relative
size of any measured value
60. Prepared by Eng Shuaib [Type here]
Surface air pressure is measured in millibars
and is shown here as isobars
61. Prepared by Eng Shuaib [Type here]
Contours can show the distribution and
relative size of any measured value
This map shows the thickness
of the Earth’s crust (in kms)
This map shows rainfall
62. Prepared by Eng Shuaib [Type here]
data for Australia (in mm)
65. Prepared by Eng Shuaib [Type here]
Contours never cross and will at some point close, although
this may be off the map. Topographic contours that close
in concentric patterns delineate hills or depressions
1 km
66. Prepared by Eng Shuaib [Type here]
1 km
Contours are drawn perpendicular to the maximum slope,
with the spacing between contours indicating
the steepness of the slope
67. Prepared by Eng Shuaib [Type here]
Valley and
stream
Ridge
Based on the shape of contours, landforms such
as valleys and ridges can be recognised
1 km
68. Prepared by Eng Shuaib [Type here]
This image highlights the real shape of two hills
and how they are shown on a contour map
40m
30m
20m
10m
0 MSL
Image from OS Map reading made easy.
69. Prepared by Eng Shuaib [Type here]
https://www.ordnancesurvey.co.uk/resources/map-reading/index.html
70. Prepared by Eng Shuaib [Type here]
You can watch a video explaining how to read
contour lines on an Ordnance Survey map
Click here to play…
The Ordnance Survey website has further information on
all aspects of maps and map reading, including how to
work out grid references and take compass bearings
https://www.ordnancesurvey.co.uk/resources/map-reading/index.html
71. Prepared by Eng Shuaib [Type here]
Practical exercise 1
Drawing contours
72. Prepared by Eng Shuaib [Type here]
900m 920m 900m
835m
835m
880m
900m
700m 1070m
800m 900m
800m
800m
1100m
970m
950m
875m
975m
Presenter
2017-11-28 13:52:05
--------------------------------------------
Sometimes topographic maps are
shown w
i
t
hheight values at a given point,
rather than contours. These are called
‘spot height’ maps and they are rather
difficult to interpret. In order to get a
better idea of the shape of the land
surface the data can be contoured.
73. Prepared by Eng Shuaib [Type here]
The easiest way to draw a contour map based on spot heights is to simply
interpolate between the known values.
As you interpolate between points make sure you label the new values,
as it quickly becomes very confusing if you don’t!
Then join identical values with smooth curves to create contours that
simulate topography
800m 800m
Start by interpolating
between individual
points, labelling new
values as you go.
750m 750m
700m
750m 800m
Then join up all
the original and
interpolated points
of equal value to
form contours.
800m
850m
750m
700m
76. Prepared by Eng Shuaib [Type here]
Completing the contouring exercise
• Based on the contour map you have created:
• Where is the highest ground?
• Where is the lowest area?
• Describe the major landforms
• Mark on the most likely course of a stream and
determine in which direction it is flowing
Presenter
2017-11-28 13:52:06
--------------------------------------------
The highest ground is in the north (
>
1
1
0
0
m
)
.
The lowest area is in the SW, in the valley b
o
t
t
o
m(<700m).
The major landforms are a sinuous valley t
h
a
ttrends SW-NE,
then W-E, flanked by a broad ridge that trends NW-SE.
The ground rises from the valley bottom to a high point in
the north. The stream is flowing from east to west.
77. Prepared by Eng Shuaib [Type here]
970m
1100m
975m
900m
800m
950
900
850
920m
800m
875m
835m
900m
880m
950m
900m
700m 1070m
835m
Presenter
2017-11-28 13:52:07
--------------------------------------------
The highest ground is in the north (
>
1
1
0
0
m
)
.
The lowest area is in the SW, in the valley b
o
t
t
o
m
(<700m).
The major landforms are a sinuous valley t
h
a
ttrends
SW-NE, then W-E, flanked by a broad ridge that
trends NW-SE. The ground rises from the valley
bottom to a high point in the north. The stream is
flowing from east to west.
79. Prepared by Eng Shuaib [Type here]
Part 2 – Map interpretation
• Contour patterns can be used to recognise
distinctive landforms such as ridges,
valleys and hills
• Contours may appear as black or coloured lines
on maps, and are often supported by colour
shading to give an impression of relief
• Cross-sections provide a useful way of visualizing
the shape of the land surface, but care needs to be
taken in their construction, particularly in terms of
90. Prepared by Eng Shuaib [Type here]
and look towards Point B? It would go downhill to
the stream and then uphill again to Point B
91. Prepared by Eng Shuaib [Type here]
A useful technique to visualise landforms is to
draw a cross-section. This one is between
Points A and B on the previous map
No vertical exaggeration
A B
200
100
Valley with stream
0 100 200 300 400 500 600 700 800 900
Distance (metres)
This image shows a similar
valley in the area, confirming
the gentle slope angles
Contour
value
(metres)
92. Prepared by Eng Shuaib [Type here]
The X axis represents distance and the Y axis height
93. Prepared by Eng Shuaib [Type here]
When drawing cross-sections it is important to
be aware how the scales affect your
perception of slope angle
2x vertical exaggeration
A B
200 Valley with stream
100
0 100 200 300 400 500 600 700 800
Distance (metres)
The purpose will dictate the
scales you use. If the cross-
section is to highlight relative
changes in topography then a
vertical exaggeration is fine,
despite the fact that it increases
the angles of all sloping lines
If there is a need to add sub-
surface geology or calculate true
slope angles, then there should
be no vertical exaggeration
Contour
value
(metres)
94. Prepared by Eng Shuaib [Type here]
Compare the effects of vertical exaggeration
on the same cross-section
Notice how the change in
vertical exaggeration
affects the angles of slope
Bear this in mind when
drawing your own cross-
sections and decide how
much (if any) vertical
exaggeration is required
104. Prepared by Eng Shuaib [Type here]
contour, looking towards Point D. Would you be able to see Point D?
105. Prepared by Eng Shuaib [Type here]
Cross-section showing the broad, gentle ridge
between Points C and D
2x vertical exaggeration
200
100
C D
Ridge
Standing at Point C you
would be unable to see
Point D because the
crest of the ridge is
higher than Point D
Here some vertical
exaggeration is
appropriate because
0 100 200 300 400 500 600
Distance (metres)
the relief is very subtle
Contour
value
(metres)
106. Prepared by Eng Shuaib [Type here]
Practical exercise 2
Constructing cross-sections
107. Prepared by Eng Shuaib [Type here]
Before constructing a cross-
section, look at the contours
and try to imagine what the
surface topography looks like
Narrower range of contours
between 140-160m indicate
a relatively flat hill top
Widely spaced contours
showing less steep slopes
compared to those in the east
Closely spaced
contours showing
a steep slope
A A’
We will now draw our own cross-
section between Cowers Lane (A)
and Chevinside (A’)
108. Prepared by Eng Shuaib [Type here]
Label each contour height and
plot the value directly onto the
Y-axis of the cross-section
A
200m
A’
150m
100m
50m
Use graph paper to mark on
every time a contour crosses
the chosen line of section
110
105
100
95
90
85
109. Prepared by Eng Shuaib [Type here]
This surface should be drawn free
hand to give a natural shape that
honours the contours
A
200m
A’
150m
100m
50m 4x vertical exaggeration
Once all the contour heights along
the section have been plotted the
land surface can be added
110. Prepared by Eng Shuaib [Type here]
A A’
4x vertical exaggeration
East
West
A completed cross-section between A-A’
The vertical scale has been exaggerated in order to show
the subtle relief. To calculate the vertical exaggeration,
divide the horizontal scale (1cm to 200m) by the
vertical scale (1cm to 50m)
So, 200/50 = 4x vertical exaggeration
200m
150m
100m
50m
0
1 km 2 km 3 km
112. Prepared by Eng Shuaib [Type here]
Comparison between a vertically exaggerated
section and a true scale cross-section
200m
150m
100m
50m
0
200m
0
No vertical exaggeration
4x vertical exaggeration
113. Prepared by Eng Shuaib [Type here]
The vertically exaggerated section provides a clearer representation
of subtle landforms, the other a true representation of slope angles
114. Prepared by Eng Shuaib [Type here]
Learning outcomes
You have now been introduced to the basic elements
of topographic maps
You have used contours to identify common landforms
and begun to visualise them in 3-D
You can now construct cross-sections and understand
the concept of vertical exaggeration
115. Prepared by Eng Shuaib [Type here]
Handouts required for the practicals
Slide 50: print out at A4, in B/W, portrait format
Slide 51: print out at A4, in colour, portrait format
Slide 52: print out at A4, in colour, portrait format
Graph paper for constructing the cross-section