The document provides an overview of the San Andreas Fault system in California, describing its topography, fault characteristics, earthquake history, and major earthquakes. Some key points:
- The San Andreas Fault is visible on the ground as a sharp linear feature that cuts across the landscape.
- Major earthquakes on the fault include the 1906 San Francisco earthquake (Magnitude 7.9), the 1857 Fort Tejon earthquake (Magnitude 7.9), the 1971 San Fernando earthquake (Magnitude 6.4), and the 1989 Loma Prieta earthquake (Magnitude 6.9).
- The section of the fault between Parkfield and San Juan Bautista displays "fault creep", or continuous slow displacement without
The San Andreas Fault is a continental transform fault that extends roughly 1,200 kilometers through California. It forms the boundary between the Pacific Plate and the North American Plate. The fault results in right-lateral strike-slip motion, with the left side moving northward and the right side moving southward. Major earthquakes are caused by the build up of stress from this motion at various segments of the fault. The fault has had a significant impact throughout California's history, causing damage from earthquakes and other natural disasters.
The document discusses different types of earthquake damage through a series of photos. It begins with background on earthquakes and then shows various examples of structural failures from earthquakes, including collapsed buildings and bridges. Subsequent photos illustrate land shifting, landslides, liquefaction, resulting fires and tsunamis, and their human impacts. The document aims to demonstrate the wide-ranging effects earthquakes can have through real examples of damage.
The document summarizes different types of volcanic eruptions and igneous activity. It discusses factors that influence the violence of eruptions like magma composition, temperature, and dissolved gases. It also describes different types of volcanoes like shield volcanoes, cinder cones, and composite cones. Plate tectonics provide mechanisms for magma generation at convergent and divergent plate boundaries as well as intraplate hotspots.
This document discusses active faults and earthquake source zones in the Philippines. It defines an active fault as one that has moved within the last 10,000 years. The three types of faults are described as normal, thrust/reverse, and strike-slip. Some of the most destructive earthquakes in Philippine history are noted, including the 1990 Luzon earthquake. The Philippine Fault Zone and Valley Fault System are identified as two of the most important active faults. Trenches are also described as earthquake generators where tectonic plates are subducting. The potential impacts of worst case earthquakes on the West Valley Fault and Manila Trench impacting Metro Manila are presented.
This document discusses key concepts around folding and faulting in the Earth's crust. It describes how fold mountains like the Himalayas are formed by compressional forces causing rock layers to bend and crumple. The Himalayas were formed by the collision of the Indian and Eurasian tectonic plates around 50 million years ago. Faulting is caused by fractures in the crust along which rock masses move, and can result in normal faults, reverse faults, and transform faults. Block mountains and rift valleys can form from the vertical displacement of rock blocks along these fault lines. The Great Rift Valley extending through Africa provides an example of a rift valley formed by tectonic forces tearing apart the Earth's crust.
Earthquacke Elastic Rebound Theory Types of WavesShakeel Ahmad
1) The document discusses the causes and types of earthquakes. It explains that earthquakes are caused by the sudden release of built-up energy between tectonic plates, which generates seismic waves.
2) It describes the elastic rebound theory of earthquakes, which states that stress gradually builds up along faults until it is suddenly released, causing the plates to snap back in an earthquake.
3) There are different types of seismic waves generated - P waves, S waves, and surface waves including Rayleigh and Love waves. P and S waves travel through the earth's interior as body waves, while surface waves travel along the surface.
Study of plate tectonics of the earth, or plate movement, Jahangir Alam
a) Wegener’s Evidence (Continental Drift)
b) History of Plate Tectonics
c) Breakup and Appearence of Pangea
WHAT IS A PLATE?
Major continental and oceanic plates include:
Types of Earth’s Crust:
Plate tectonics (from the Late Latin tectonicus) is a scientific theory which describes the large scale motions of Earth's lithosphere.
THE DYNAMIC EARTH:
The earth is a dynamic planet, continuously changing both externally and internally. The earth’s surface is constantly being changed by endo-genetic processes resulting in volcanism and tectonism, and exogenetic processes such as erosion and deposition. These processes have been active throughout geological history. The processes that change the surface feature are normally very slow (erosion and deposition) except some catastrophic changes that occur instantaneously as in the case of volcanism or earthquakes. The interior of the earth is also in motion. Deeper inside the earth, the liquid core probably flows at a geologically rapid rate of a few tenths of mm/s. Several hypotheses attempted to explain the dynamism of the earth.
+ Horizontal movement hypothesis
+ Continental drift, displacement hypothesis
Development of the plate tectonic theory.
Plate tectonic theory arose out of the hypothesis of continental drift proposed by Alfred Wegener in 1912. He suggested that the present continents once formed a single land mass that drifted apart, thus releasing the continents from the Earth's core and likening them to "icebergs" of low density granite floating on a sea of denser basalt.
Seafloor Spreading
The first evidence that the lithospheric plates did move came with the discovery of variable magnetic field direction in rocks of differing ages.
The document discusses the structure and composition of the Earth, including the crust, mantle, outer core, and inner core. It also discusses plate tectonics and the different types of plate boundaries: constructive, destructive, conservative, and collision. At destructive boundaries, oceanic plates are subducted under continental plates, forming volcanoes. At collision boundaries, continental plates push together to form mountain ranges. At constructive boundaries, plates move apart and new crust is formed.
The San Andreas Fault is a continental transform fault that extends roughly 1,200 kilometers through California. It forms the boundary between the Pacific Plate and the North American Plate. The fault results in right-lateral strike-slip motion, with the left side moving northward and the right side moving southward. Major earthquakes are caused by the build up of stress from this motion at various segments of the fault. The fault has had a significant impact throughout California's history, causing damage from earthquakes and other natural disasters.
The document discusses different types of earthquake damage through a series of photos. It begins with background on earthquakes and then shows various examples of structural failures from earthquakes, including collapsed buildings and bridges. Subsequent photos illustrate land shifting, landslides, liquefaction, resulting fires and tsunamis, and their human impacts. The document aims to demonstrate the wide-ranging effects earthquakes can have through real examples of damage.
The document summarizes different types of volcanic eruptions and igneous activity. It discusses factors that influence the violence of eruptions like magma composition, temperature, and dissolved gases. It also describes different types of volcanoes like shield volcanoes, cinder cones, and composite cones. Plate tectonics provide mechanisms for magma generation at convergent and divergent plate boundaries as well as intraplate hotspots.
This document discusses active faults and earthquake source zones in the Philippines. It defines an active fault as one that has moved within the last 10,000 years. The three types of faults are described as normal, thrust/reverse, and strike-slip. Some of the most destructive earthquakes in Philippine history are noted, including the 1990 Luzon earthquake. The Philippine Fault Zone and Valley Fault System are identified as two of the most important active faults. Trenches are also described as earthquake generators where tectonic plates are subducting. The potential impacts of worst case earthquakes on the West Valley Fault and Manila Trench impacting Metro Manila are presented.
This document discusses key concepts around folding and faulting in the Earth's crust. It describes how fold mountains like the Himalayas are formed by compressional forces causing rock layers to bend and crumple. The Himalayas were formed by the collision of the Indian and Eurasian tectonic plates around 50 million years ago. Faulting is caused by fractures in the crust along which rock masses move, and can result in normal faults, reverse faults, and transform faults. Block mountains and rift valleys can form from the vertical displacement of rock blocks along these fault lines. The Great Rift Valley extending through Africa provides an example of a rift valley formed by tectonic forces tearing apart the Earth's crust.
Earthquacke Elastic Rebound Theory Types of WavesShakeel Ahmad
1) The document discusses the causes and types of earthquakes. It explains that earthquakes are caused by the sudden release of built-up energy between tectonic plates, which generates seismic waves.
2) It describes the elastic rebound theory of earthquakes, which states that stress gradually builds up along faults until it is suddenly released, causing the plates to snap back in an earthquake.
3) There are different types of seismic waves generated - P waves, S waves, and surface waves including Rayleigh and Love waves. P and S waves travel through the earth's interior as body waves, while surface waves travel along the surface.
Study of plate tectonics of the earth, or plate movement, Jahangir Alam
a) Wegener’s Evidence (Continental Drift)
b) History of Plate Tectonics
c) Breakup and Appearence of Pangea
WHAT IS A PLATE?
Major continental and oceanic plates include:
Types of Earth’s Crust:
Plate tectonics (from the Late Latin tectonicus) is a scientific theory which describes the large scale motions of Earth's lithosphere.
THE DYNAMIC EARTH:
The earth is a dynamic planet, continuously changing both externally and internally. The earth’s surface is constantly being changed by endo-genetic processes resulting in volcanism and tectonism, and exogenetic processes such as erosion and deposition. These processes have been active throughout geological history. The processes that change the surface feature are normally very slow (erosion and deposition) except some catastrophic changes that occur instantaneously as in the case of volcanism or earthquakes. The interior of the earth is also in motion. Deeper inside the earth, the liquid core probably flows at a geologically rapid rate of a few tenths of mm/s. Several hypotheses attempted to explain the dynamism of the earth.
+ Horizontal movement hypothesis
+ Continental drift, displacement hypothesis
Development of the plate tectonic theory.
Plate tectonic theory arose out of the hypothesis of continental drift proposed by Alfred Wegener in 1912. He suggested that the present continents once formed a single land mass that drifted apart, thus releasing the continents from the Earth's core and likening them to "icebergs" of low density granite floating on a sea of denser basalt.
Seafloor Spreading
The first evidence that the lithospheric plates did move came with the discovery of variable magnetic field direction in rocks of differing ages.
The document discusses the structure and composition of the Earth, including the crust, mantle, outer core, and inner core. It also discusses plate tectonics and the different types of plate boundaries: constructive, destructive, conservative, and collision. At destructive boundaries, oceanic plates are subducted under continental plates, forming volcanoes. At collision boundaries, continental plates push together to form mountain ranges. At constructive boundaries, plates move apart and new crust is formed.
This document contains a science lesson on plate tectonics. It begins with welcome messages and learning objectives. It then reviews concepts about convergent plate boundaries through multiple choice questions and answers. Examples and diagrams are provided to illustrate subduction zones and the three types of convergent boundaries. The document continues with a similar format reviewing concepts about divergent plate boundaries through true/false questions. Examples are used to explain the two types of divergent boundaries and the motion and features associated with each.
The document discusses how stress deforms and shapes the Earth's crust through folding, faulting, and other tectonic processes. It describes the three main types of folds and faults, and how convergent, divergent, and strike-slip boundaries each produce different styles of deformation. Various mountain-building processes are also summarized, including folded mountains, fault-block mountains, and volcanic mountains formed at plate boundaries.
Earthquakes occur along faults in the Earth's crust where blocks of rock move due to stress. There are three main types of faults - normal faults where one block moves down, reverse faults where one block moves up, and strike-slip faults where blocks move horizontally. When stress is released, energy radiates outward from the focus in the form of seismic waves, including primary, secondary, and surface waves. Seismographs can detect and record these waves to locate the epicenter and measure the earthquake's magnitude. Earthquakes can cause severe damage through ground shaking, landslides, fires and liquefaction, but damage can be reduced through monitoring, predicting earthquake activity, and enforcing strict building codes for earthquake-resistant construction.
This document discusses plate tectonics and the structure of the Earth. It explains that the Earth's crust is broken into huge plates that drift atop the mantle. It describes the three layers of the Earth - the crust, mantle, and core. It discusses how the continents were once joined together in a supercontinent called Pangaea before drifting apart due to plate tectonics. There are three types of plate boundaries - divergent boundaries where plates move apart, convergent boundaries where they move together, and transform boundaries where they slide past each other.
This document summarizes a presentation on stress and its types. It defines stress as a force acting on an area. It describes three main types of stress: compressional stress which causes rocks to push together and can result in reverse faults; tensional stress which pulls rocks apart and can cause normal faults; and shear stress which acts in opposite directions parallel to each other and can produce strike-slip faults. It concludes that plate tectonics movements generate stress at plate boundaries through compression at converging boundaries and tension at diverging boundaries.
Earth System History, Timeline of Earth Events, Geologic History Earth Scienc...www.sciencepowerpoint.com
This PowerPoint is one small part of the Geology Topics unit from www.sciencepowerpoint.com. This unit consists of a five part 6000+ slide PowerPoint roadmap, 14 page bundled homework package, modified homework, detailed answer keys, 12 pages of unit notes for students who may require assistance, follow along worksheets, and many review games. The homework and lesson notes chronologically follow the PowerPoint slideshow. The answer keys and unit notes are great for support professionals. The activities and discussion questions in the slideshow are meaningful. The PowerPoint includes built-in instructions, visuals, and review questions. Also included are critical class notes (color coded red), project ideas, video links, and review games. This unit also includes four PowerPoint review games (110+ slides each with Answers), 38+ video links, lab handouts, activity sheets, rubrics, materials list, templates, guides, 6 PowerPoint review Game, and much more. Also included is a 190 slide first day of school PowerPoint presentation.
Areas of Focus within The Geology Topics Unit: -Plate Tectonics, Evidence for Plate Tectonics, Pangea, Energy Waves, Layers of the Earth, Heat Transfer, Types of Crust, Plate Boundaries, Hot Spots, Volcanoes, Positives and Negatives of Volcanoes, Types of Volcanoes, Parts of a Volcano, Magma, Types of Lava, Viscosity, Earthquakes, Faults, Folds, Seismograph, Richter Scale, Seismograph, Tsunami's, Rocks, Minerals, Crystals, Uses of Minerals, Types of Crystals, Physical Properties of Minerals, Rock Cycle, Common Igneous Rocks, Common Sedimentary Rocks, Common Metamorphic Rocks.
This unit aligns with the Next Generation Science Standards and with Common Core Standards for ELA and Literacy for Science and Technical Subjects. See preview for more information
If you have any questions please feel free to contact me. Thanks again and best wishes. Sincerely, Ryan Murphy M.Ed www.sciencepowerpoint@gmail.com
This presentation gives detailed information about earthquake , its types , waves , faults , especially in asian countries .A detailed case study of earthquake In NEPAL in 2015 is also covered in this with pictures . Also how it is measured and its warning system , vulnerability, deployment and future aspects has been covered .
HOPE YOU LIKE IT AND GET FULL INFORMATION!!!!!
1. The document discusses different types of mountain formation including folded mountains formed by plate collisions at convergent boundaries, fault-block mountains formed by uplift along normal faults, and domed mountains formed by uplifting of basement rock.
2. Mountain building occurs through processes like folding, faulting, and metamorphism of rock layers as tectonic plates converge. Different mountain types result from ocean-ocean, ocean-continental, and continental-continental plate collisions.
3. After mountain building, thickened crust undergoes isostatic adjustment through regional uplift to reach a new equilibrium with the mantle.
The document discusses various geological structures including outcrops, rock deformation, folds, faults, and joints. It defines key terms like strike and dip which are used to describe the orientation of deformed rocks. It explains different types of folds such as anticlines, synclines, overturned folds, and plunging folds. It also describes various types of faults including normal faults, thrust faults, strike-slip faults, and transform faults. Additionally, it discusses joints as fractures in rocks where there is no relative displacement and classifies joints based on their orientation. In summary, the document provides an overview of structural geology and the terminology used to describe deformed rocks and geological structures.
The document discusses plate tectonics and describes how the Earth's lithosphere is broken into plates that move over time. It explains that plate tectonics built upon Alfred Wegener's theory of continental drift, which proposed that the continents were once joined together in a supercontinent called Pangaea. There are nine major tectonic plates and three types of plate boundaries - divergent boundaries which create mid-ocean ridges and rift valleys, convergent boundaries which cause subduction and mountain building, and transform boundaries where plates slide past each other like the San Andreas Fault. Convection currents in the Earth's mantle provide the driving force for plate movements.
Prentice Hall Earth Science ch10 volcanoesTim Corner
The document discusses factors that affect the violence of volcanic eruptions including the composition, temperature, and dissolved gases of magma. More viscous magma produces more violent eruptions as gases cannot escape as easily. There are three main types of volcanoes - shield volcanoes formed from fluid basaltic lava, cinder cones formed from pyroclastic material from a single vent, and composite cones which are the most violent type formed from both lava and pyroclastic material. The document also briefly mentions plutons, which are intrusive igneous rocks that form from cooling magma underground.
This document describes different types of faults and what causes earthquakes. It explains that normal faults occur due to tension and drop one side down, while thrust faults occur due to compression and raise one side up. Strike-slip faults cause the sides to scrape past each other due to shearing. Earthquakes are caused when plates get stuck and release energy in sudden jerks, sending out seismic waves from the focus. The epicenter is where the waves reach the surface above the focus.
The document discusses various shoreline processes driven by wave motion. It explains that waves form as energy moves through water, with water particles moving in a circular pattern. As waves approach shallow water, they break due to friction, piling up water that rushes onto the shore and moves sediment. Waves typically approach the shore at an angle and carry sediment along the coast in a zig-zag pattern through longshore transport. Breaking waves can also transport sediment diagonally inland during swash before the sediment moves seaward during backwash.
The document discusses earthquakes, including their causes, types, effects, and measurement. Earthquakes are caused by the sudden release of stress along faults within the earth's crust. They can be shallow, mid-focus, or deep, and cause both primary (P) waves and secondary (S) waves. The magnitude and intensity of quakes are measured using the Richter scale and Mercalli scale, respectively. Major quakes frequently occur at plate boundaries and have caused widespread damage throughout history.
Earthquakes are caused by the sudden release of elastic energy stored in rock. The focus is where the earthquake originates within the earth, and the epicenter is the point directly above on the surface. Seismographs record earthquake waves, including P and S body waves and surface waves, which can be used to locate the epicenter. Earth's interior consists of layers defined by composition - the crust, mantle, and core - and by physical properties like density and rigidity.
This document discusses various coastal landforms and processes. It begins with defining terms related to waves and wave action. It then explains processes of marine erosion and how they can shape cliff coastlines and form wave-cut platforms. It describes how waves can transport and deposit sediment. Landforms like spits, bars, and salt marshes are discussed along with their formation. Finally, it covers coral reef types and theories about their formation, and how sea level changes can impact coral reefs.
The document discusses the theory of plate tectonics. [1] The Earth's crust and upper mantle are broken into sections called plates that move around on top of the mantle. [2] The lithosphere comprises the crust and part of the upper mantle and "floats" on the asthenosphere, which is the plastic layer below. [3] There are two types of plates - ocean plates below oceans and continental plates below continents.
This report contains the brief introduction to earthquake,its effect,causes etc..
And case study of kuchha(bhuj),Gujarat Earthquake on 26th january,2001
The San Andreas Fault is a continental transform fault that extends through California for over 800 miles. It forms the boundary between the Pacific and North American tectonic plates, with the Pacific plate moving northward. The fault is divided into three segments with varying earthquake risks, with the southern segment posing the greatest risk as it passes within 35 miles of Los Angeles. Studies of the fault seek to better understand and predict earthquake activity to mitigate damage from future large quakes.
The San Andreas Fault system runs over 800 miles through California. It is located between the Pacific and North American tectonic plates, which are slowly moving past each other in opposite directions. Major earthquakes regularly occur along the fault as the plates shift, causing damage through ground shaking, landslides, and other effects. Scientists study the fault to better understand earthquake risks and how to mitigate future disasters.
This document contains a science lesson on plate tectonics. It begins with welcome messages and learning objectives. It then reviews concepts about convergent plate boundaries through multiple choice questions and answers. Examples and diagrams are provided to illustrate subduction zones and the three types of convergent boundaries. The document continues with a similar format reviewing concepts about divergent plate boundaries through true/false questions. Examples are used to explain the two types of divergent boundaries and the motion and features associated with each.
The document discusses how stress deforms and shapes the Earth's crust through folding, faulting, and other tectonic processes. It describes the three main types of folds and faults, and how convergent, divergent, and strike-slip boundaries each produce different styles of deformation. Various mountain-building processes are also summarized, including folded mountains, fault-block mountains, and volcanic mountains formed at plate boundaries.
Earthquakes occur along faults in the Earth's crust where blocks of rock move due to stress. There are three main types of faults - normal faults where one block moves down, reverse faults where one block moves up, and strike-slip faults where blocks move horizontally. When stress is released, energy radiates outward from the focus in the form of seismic waves, including primary, secondary, and surface waves. Seismographs can detect and record these waves to locate the epicenter and measure the earthquake's magnitude. Earthquakes can cause severe damage through ground shaking, landslides, fires and liquefaction, but damage can be reduced through monitoring, predicting earthquake activity, and enforcing strict building codes for earthquake-resistant construction.
This document discusses plate tectonics and the structure of the Earth. It explains that the Earth's crust is broken into huge plates that drift atop the mantle. It describes the three layers of the Earth - the crust, mantle, and core. It discusses how the continents were once joined together in a supercontinent called Pangaea before drifting apart due to plate tectonics. There are three types of plate boundaries - divergent boundaries where plates move apart, convergent boundaries where they move together, and transform boundaries where they slide past each other.
This document summarizes a presentation on stress and its types. It defines stress as a force acting on an area. It describes three main types of stress: compressional stress which causes rocks to push together and can result in reverse faults; tensional stress which pulls rocks apart and can cause normal faults; and shear stress which acts in opposite directions parallel to each other and can produce strike-slip faults. It concludes that plate tectonics movements generate stress at plate boundaries through compression at converging boundaries and tension at diverging boundaries.
Earth System History, Timeline of Earth Events, Geologic History Earth Scienc...www.sciencepowerpoint.com
This PowerPoint is one small part of the Geology Topics unit from www.sciencepowerpoint.com. This unit consists of a five part 6000+ slide PowerPoint roadmap, 14 page bundled homework package, modified homework, detailed answer keys, 12 pages of unit notes for students who may require assistance, follow along worksheets, and many review games. The homework and lesson notes chronologically follow the PowerPoint slideshow. The answer keys and unit notes are great for support professionals. The activities and discussion questions in the slideshow are meaningful. The PowerPoint includes built-in instructions, visuals, and review questions. Also included are critical class notes (color coded red), project ideas, video links, and review games. This unit also includes four PowerPoint review games (110+ slides each with Answers), 38+ video links, lab handouts, activity sheets, rubrics, materials list, templates, guides, 6 PowerPoint review Game, and much more. Also included is a 190 slide first day of school PowerPoint presentation.
Areas of Focus within The Geology Topics Unit: -Plate Tectonics, Evidence for Plate Tectonics, Pangea, Energy Waves, Layers of the Earth, Heat Transfer, Types of Crust, Plate Boundaries, Hot Spots, Volcanoes, Positives and Negatives of Volcanoes, Types of Volcanoes, Parts of a Volcano, Magma, Types of Lava, Viscosity, Earthquakes, Faults, Folds, Seismograph, Richter Scale, Seismograph, Tsunami's, Rocks, Minerals, Crystals, Uses of Minerals, Types of Crystals, Physical Properties of Minerals, Rock Cycle, Common Igneous Rocks, Common Sedimentary Rocks, Common Metamorphic Rocks.
This unit aligns with the Next Generation Science Standards and with Common Core Standards for ELA and Literacy for Science and Technical Subjects. See preview for more information
If you have any questions please feel free to contact me. Thanks again and best wishes. Sincerely, Ryan Murphy M.Ed www.sciencepowerpoint@gmail.com
This presentation gives detailed information about earthquake , its types , waves , faults , especially in asian countries .A detailed case study of earthquake In NEPAL in 2015 is also covered in this with pictures . Also how it is measured and its warning system , vulnerability, deployment and future aspects has been covered .
HOPE YOU LIKE IT AND GET FULL INFORMATION!!!!!
1. The document discusses different types of mountain formation including folded mountains formed by plate collisions at convergent boundaries, fault-block mountains formed by uplift along normal faults, and domed mountains formed by uplifting of basement rock.
2. Mountain building occurs through processes like folding, faulting, and metamorphism of rock layers as tectonic plates converge. Different mountain types result from ocean-ocean, ocean-continental, and continental-continental plate collisions.
3. After mountain building, thickened crust undergoes isostatic adjustment through regional uplift to reach a new equilibrium with the mantle.
The document discusses various geological structures including outcrops, rock deformation, folds, faults, and joints. It defines key terms like strike and dip which are used to describe the orientation of deformed rocks. It explains different types of folds such as anticlines, synclines, overturned folds, and plunging folds. It also describes various types of faults including normal faults, thrust faults, strike-slip faults, and transform faults. Additionally, it discusses joints as fractures in rocks where there is no relative displacement and classifies joints based on their orientation. In summary, the document provides an overview of structural geology and the terminology used to describe deformed rocks and geological structures.
The document discusses plate tectonics and describes how the Earth's lithosphere is broken into plates that move over time. It explains that plate tectonics built upon Alfred Wegener's theory of continental drift, which proposed that the continents were once joined together in a supercontinent called Pangaea. There are nine major tectonic plates and three types of plate boundaries - divergent boundaries which create mid-ocean ridges and rift valleys, convergent boundaries which cause subduction and mountain building, and transform boundaries where plates slide past each other like the San Andreas Fault. Convection currents in the Earth's mantle provide the driving force for plate movements.
Prentice Hall Earth Science ch10 volcanoesTim Corner
The document discusses factors that affect the violence of volcanic eruptions including the composition, temperature, and dissolved gases of magma. More viscous magma produces more violent eruptions as gases cannot escape as easily. There are three main types of volcanoes - shield volcanoes formed from fluid basaltic lava, cinder cones formed from pyroclastic material from a single vent, and composite cones which are the most violent type formed from both lava and pyroclastic material. The document also briefly mentions plutons, which are intrusive igneous rocks that form from cooling magma underground.
This document describes different types of faults and what causes earthquakes. It explains that normal faults occur due to tension and drop one side down, while thrust faults occur due to compression and raise one side up. Strike-slip faults cause the sides to scrape past each other due to shearing. Earthquakes are caused when plates get stuck and release energy in sudden jerks, sending out seismic waves from the focus. The epicenter is where the waves reach the surface above the focus.
The document discusses various shoreline processes driven by wave motion. It explains that waves form as energy moves through water, with water particles moving in a circular pattern. As waves approach shallow water, they break due to friction, piling up water that rushes onto the shore and moves sediment. Waves typically approach the shore at an angle and carry sediment along the coast in a zig-zag pattern through longshore transport. Breaking waves can also transport sediment diagonally inland during swash before the sediment moves seaward during backwash.
The document discusses earthquakes, including their causes, types, effects, and measurement. Earthquakes are caused by the sudden release of stress along faults within the earth's crust. They can be shallow, mid-focus, or deep, and cause both primary (P) waves and secondary (S) waves. The magnitude and intensity of quakes are measured using the Richter scale and Mercalli scale, respectively. Major quakes frequently occur at plate boundaries and have caused widespread damage throughout history.
Earthquakes are caused by the sudden release of elastic energy stored in rock. The focus is where the earthquake originates within the earth, and the epicenter is the point directly above on the surface. Seismographs record earthquake waves, including P and S body waves and surface waves, which can be used to locate the epicenter. Earth's interior consists of layers defined by composition - the crust, mantle, and core - and by physical properties like density and rigidity.
This document discusses various coastal landforms and processes. It begins with defining terms related to waves and wave action. It then explains processes of marine erosion and how they can shape cliff coastlines and form wave-cut platforms. It describes how waves can transport and deposit sediment. Landforms like spits, bars, and salt marshes are discussed along with their formation. Finally, it covers coral reef types and theories about their formation, and how sea level changes can impact coral reefs.
The document discusses the theory of plate tectonics. [1] The Earth's crust and upper mantle are broken into sections called plates that move around on top of the mantle. [2] The lithosphere comprises the crust and part of the upper mantle and "floats" on the asthenosphere, which is the plastic layer below. [3] There are two types of plates - ocean plates below oceans and continental plates below continents.
This report contains the brief introduction to earthquake,its effect,causes etc..
And case study of kuchha(bhuj),Gujarat Earthquake on 26th january,2001
The San Andreas Fault is a continental transform fault that extends through California for over 800 miles. It forms the boundary between the Pacific and North American tectonic plates, with the Pacific plate moving northward. The fault is divided into three segments with varying earthquake risks, with the southern segment posing the greatest risk as it passes within 35 miles of Los Angeles. Studies of the fault seek to better understand and predict earthquake activity to mitigate damage from future large quakes.
The San Andreas Fault system runs over 800 miles through California. It is located between the Pacific and North American tectonic plates, which are slowly moving past each other in opposite directions. Major earthquakes regularly occur along the fault as the plates shift, causing damage through ground shaking, landslides, and other effects. Scientists study the fault to better understand earthquake risks and how to mitigate future disasters.
- Conservative (passive) plate boundaries occur where two tectonic plates slide horizontally past one another in opposite directions, causing friction and earthquakes along the fault line where they meet.
- As the plates move, a gap is created behind each one called a fault. The best known example is the San Andreas Fault in California, where the Pacific and North American Plates slide past each other.
- Major earthquakes, like the 1906 San Francisco earthquake, are caused by the built-up friction along the fault line being suddenly released as the plates shift. These earthquakes can cause widespread damage.
Sonoma County is located in Northern California, bounded by mountains, wetlands, coastal bluffs, and fertile farmland. The San Andreas Fault runs through the county, producing occasional earthquakes. The climate varies from coastal to inland areas, with wet, cool winters and dry, hot summers. Precipitation ranges from 45 inches annually on the coast to half that inland. Native Miwok Indians originally inhabited the area, followed by Spanish and Mexican settlers who established ranches in the early 19th century. Agriculture, including grape vines imported in the mid-19th century, remains an important part of the county's economy today.
The Corps of Engineers responded immediately to address the unfolding crisis caused by the 1980 eruption of Mount St. Helens. They focused first on flood control and restoring river navigability. In the following months, the Corps cleared debris, dredged channels, and raised levees to protect against potential flooding and restore normal flow. Longer term, the eruption influenced volcanology research and the development of the National Volcano Early Warning System to better monitor volcanoes and warn the public of eruptions.
The Mount St. Helens eruption in 1980 caused widespread damage and required both immediate and long-term responses. The U.S. Army Corps of Engineers immediately worked to address floods, restore river navigability, and clear debris. They also raised levees and dredged rivers in the following months. Long-term, the eruption influenced volcanology research, leading to the development of the National Volcano Early Warning System to better monitor volcanoes and warn the public of eruptions.
The 1906 San Francisco earthquake struck Northern California on April 18th with a magnitude of 7.8. Over 3,000 people were killed and 80% of San Francisco was destroyed by the earthquake and subsequent fires. The earthquake was caused by movement along the San Andreas Fault, where the Pacific and North American tectonic plates meet. Survivors were left homeless and faced hardship as the city worked to recover from the devastating natural disaster.
Mormon rocks etiwanda preserve power pointlschmidt1170
The document provides information about a field trip to Mormon Rocks and the Etiwanda Preserve. It discusses how the Mormon Rocks were formed by the San Andreas Fault and named after Mormon settlers. It describes the geology of the San Andreas Fault and the granular structure of the Mormon Rocks. It then gives details about the vegetation and wildlife at the Etiwanda Preserve, which was established to preserve habitat, and impacts from the Grand Prix Fire that burned over 60,000 acres.
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CARIBBEAN STUDIES Instrumental seismicity in jamaicacapesociology
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1. Topography, Fault Characteristics, and
Earthquake History Along the San
Andreas System
• When viewed from an
airplane, almost any part
of the San Andreas Fault
appears on the ground as a
sharp linear scar that cuts
across all features of the
landscape, displacing
ridges, valleys, and
streams faster than they
can be smoothed by
erosion and deposition. The San Andreas as it crosses the
Carrizo Plain in central California
2. • At the northern end of the
fault is the Mendocino
Triple Junction. This
boundary is the junction
between the Pacific,
North American, and
Gorda Plates, officially
placed at the isolated
village of Petrolia in
Humboldt County, and
epicenter of 3 large
earthquakes in 1992. On
April 25 and 26, 1992,
three earthquakes with
magnitudes between 6.0
and 7.0 shook the region.
This is one of the most
seismically active parts of
the state.
3. • From the Mendocino triple junction south to
Point Arena, the San Andreas Fault Zone lies
offshore. At Point Arena, the fault emerges from
the Pacific and can be traced to Fort Ross, where
it again runs offshore.
Point Arena
San Andreas Fault
Zone
4. • Further south, Tomales Bay is one of the
San Andreas Faults’ most striking
landforms, separating the Point Reyes
Peninsula from the mainland along a
narrow slash that extends south of Tomales
Bay to Bolinas Bay. From Bolinas Bay the
fault lies offshore, west of San Francisco,
until it intersects the San Francisco
Peninsula and remains on land for the rest
of its length.
Point Reyes Peninsula
Bolinas Lagoon, the San Andreas runs
beneath the lake, the North American Plate
is on the right, Pacific Plate is on the left.
Another view
of the
Tomales
Bay, the
North
American
Plate is on
the right,
Pacific Plate
on the left.
5. •As the San Andreas
system crosses the San
Francisco Bay Area,
movement is shared among
4 major right-lateral fault
zones, which in addition to
the San Andreas includes
the Rodgers Creek,
Hayward, Calaveras
Faults.
Rodgers Creek Fault
Hayward Fault
Calaveras Fault
San Andreas Fault
6. 1906 San Francisco Earthquake
• San Francisco in 1906 was a
prosperous city of 400,000
inhabitants, and a major center
for world trade and banking.
But at 5:12 AM on April 18, a
great earthquake brought
disaster to San Francisco and
surrounding areas. Centered on
the San Andreas Fault west of
the city, the earthquake
registered about ML 8.2, and was
felt as far away as Los Angeles
and central Nevada.
Golden Gate Avenue in San Francisco,
1906 following the earthquake but before
the fire that destroyed many of the
buildings
7. • In addition, a slight bend
in the San Andreas in the
Santa Cruz Mountains
area appears to have
caused the fault to
generate numerous faults
throughout the region.
One of these, the Sargent
Fault, is believed
responsible for the ML 7.1
(MW of 7.0) 1989 Loma
Prieta Earthquake.
Damage in Marina District, San Francisco
Damage
to historic
buildings
in Santa
Cruz
8. Central California: The Creeping
Segment and the Parkfield Area
• Between San Juan Bautista and Parkfield, the San
Andreas system behaves very differently from its
neighboring segments. This central segment
experiences numerous small earthquakes, usually
with magnitudes less than 4.0. The Calaveras and
Hayward Faults east of San Francisco Bay show a
similar pattern.
Left: The San
Andreas Fault as it
cuts just to the south
of the town of
Parkfield.
Right: Creeping
along the San
Andreas Fault has
caused offset across
this road.
9. • These faults display a
relatively constant, slow
displacement called
fault creep. The
continuous offset
displaces sidewalks,
curbs, and other cultural
features along the
faults.
Offset of culvert near Almaden Cienega Winery near Hollister
Distorted
Fence
across the
San
Andreas
Fault,,
Melendy
Ranch
Curb offset
in 1974
(above) and
in 1993
(below)
Hayward
10. The Carrizo Plain and the Fort
Tejon Earthquake
• Along this relatively straight,
relatively simple segment of the fault,
one can view the offset streams,
compressional ridges, linear valleys,
and sag ponds that characterize a
transform fault on land.
Aerial view of the San Andreas
as it crosses the Carrizo Plain
Wallace Creek,
offset by motion
along the San
Andreas
11. The 1857 Fort Tejon Earthquake
• On January 9, 1857, an
enormous earthquake
ruptured the San Andreas
Fault from Parkfield through
the Big Bend segment and
southeast at least to
Wrightwood, a total of at
least 360 kilometers. Fort
Tejon, a military outpost at
the southernmost end of the
Carrizo Plain was one of few
population centers near the
epicenter. There the ground
shook for 1 to 3 minutes.
The earthquake produced as
much as 9 meters of offset in
the Carrizo Plain and 3 to 4
meters in the Mojave Desert.
San Andreas Fault
Epicenter
1857 rupture
Garlock Fault
Rupture area (in red) of 1857 Ft. Tejon earthquake
12. The Big Bend: The San Andreas Fault System
in the Transverse Ranges and the San Gabriel
and San Bernardino Mountains
• From its junction with the
Garlock Fault, the San
Andreas Fault makes a
marked bend to the
southeast for about 120 km.
This segment is
appropriately referred to as
the Big Bend. Because of
the significant component
of compression in the
region, rocks are actively
being squeezed and
uplifted.
13. • As a result of the
compression, spectacular
mountain ranges have been
thrown up along the margins
of the fault, such as the San
Gabriel, San Bernardino,
and San Jacinto ranges. The
steep mountain slopes have
shed enormous quantities of
debris that are spread across
the range fronts in large
alluvial fans. The fans,
increasingly occupied by
high-density housing and
commercial developments,
are in many places cut by
reverse faults caused by
compression in this area.
14. • The right-lateral motion
along the San Andreas
system is taken up by a
number of different
number of fault strands
in the Big Bend segment
including the San
Jacinto, Whittier-
Elsinore, and Newport-
Inglewood Faults. The
San Andreas itself
defines the eastern end of
the Big Bend segment,
and at present is the most
active fault strand.
San Andreas Fault
San Jacinto Fault
Newport-Inglewood Fault
Whittier-Elsinore Fault
15. The 1933 Long Beach Earthquake
• The Long Beach earthquake
centered on the Newport-
Inglewood Fault struck March 10,
1933. Although it was a moderate
event with a moment magnitude of
6.2, the earthquake killed 120
people, injured hundreds, and
caused over $40 million in
damage. Poor construction
accounted for tragic failures of
school structures in the Long
Beach area (see left). Luckily, the
schools were almost empty when
the quake hit at 5:54 PM.
Following the earthquake, the
California legislature passed the
Field Act which requires state
approval and inspection of both
plans and construction of school
buildings.
16. The 1971 San Fernando Earthquake
• Early on the morning of February 9,
1971, a moderate earthquake (M 6.4)
shook the densely populated San
Fernando Valley. Although lasting
only 15 seconds, the earthquake
killed 58 people, destroyed 2
hospitals and a modern freeway
overpass, and caused over $500
million in damage. Had the shaking
lasted a mere 5 seconds longer the
tragedy would have been far worse.
The Van Norman Dam, built in 1915
overlooking the San Fernando
Valley, broke during the shaking.
Partly because the reservoir was only
half full, the dam held, and the
80,000 residents below were spared
from a disastrous flood.
17. • Due to this earthquake, three
important acts were passed by
the California legislature, the
Alquist-Priolo Earthquake
Zoning Act, the Dam Safety
Act and the Hospital Safety
Act. The Alquist-Priolo Act
prohibits the construction of
most human-occupied
structures within 50 feet of an
active fault. The Dam Safety
Act requires evaluation of the
safety of existing dams in
California and the Hospital
Safety act called for the
strengthening of construction
standards for hospitals.
Collapse of the Olive View Hospital, San
Fernando
Near collapse of the Van Norman Dam, San Fernando
18. Pallett Creek and Earthquake
Frequency
• Along the bank of Pallett
Creek, about 55 km northeast of
Los Angeles, is a marsh that
has been cut by a strand of the
San Andreas Fault. Deposits
here record amazing evidence
of past earthquakes on the San
Andreas Fault in southern
California. At least 12
earthquakes have broken the
sediments at Pallett Creek in the
past 1700 years at this site,
giving geologists the best
information about earthquake
history The San Andreas Fault as it cuts through and along the San Andreas.
offsets coal seams at Pallett Creek
19. The Southern San Andreas, the Salton
Trough and the Imperial Valley
• The Salton Trough, a
long desert valley that
contains both the
Imperial Valley and the
Salton Sea, is the most
striking feature of the
southern San Andreas
system. Bordered on
the east by the San
Andreas Fault and on
the west by the San
Jacinto Fault Zone, the
Salton Trough is about
390 kilometers long.
Map of the Salton Trough.
LANDSAT photo of the Salton
Trough region.
20. The San Andreas as it crosses just
north of the Salton Sea, near Palm
Springs.
The San Andreas as it crosses
through the Mecca Hills on
the eastern shore of the Salton
Sea.
21. • The transform plate boundary in
the region of the Salton Trough
shows some features
characteristic of the divergent
boundary immediately to the
south in Baja California,
Mexico. The trough is a pull-apart
basin that has formed
during the past 4 million years
as the Peninsular Ranges have
pulled away from North
America. The spreading has not
yet caused a mid-ocean ridge to
appear, as it has further south.
However volcanic rocks on the
southeastern side of the Salton
Sea appeared about 16,000
years ago.
Salton Sea
The San Andreas Fault (in red) as it
cuts across the Mecca Hills adjacent to
the Salton Sea
22. • Clues within these volcanic
rocks suggest that mid-ocean
ridge magma is
interacting with the
continental crust beneath the
Salton Trough and that
rifting is extending
northward from the Gulf of
California. The high flow
of heat in the area due to
rising magma is enough to
produce several geothermal
reservoirs; some of which
have been tapped for
geothermal energy.
Space shuttle image of Salton Sea and Gulf of
California.
Volcanic rocks at the southern end of the Salton Sea.
Evidence of magma close to the surface.
23. The Eastern California Shear
Zone
• A zone of faults known as the
Eastern California Shear Zone
(ECSZ) runs parallel to the San
Andreas Fault through the central
Mojave Desert. Many of the faults
are young normal faults, but right-lateral
motion also occurs on several,
including the Johnson Valley (JVF),
Homestead Valley (HVF), Emerson
(EF), Camprock (CRF), Lavic Lake
(LLF) and Bullion Faults (BF). The
pattern of activity on these faults
indicates they could correctly be
considered part of the boundary
between the Pacific and North
American Plates.
CRF
EF
HVF
JVF
LLF
BF
San Andreas
24. • Several moderate earthquakes have
ruptured the faults of the ECSZ,
including the 1975 Galway Lake (ML
5.2), the 1979 Homestead Valley (ML
5.6) and the April 1992 Joshua Tree
(ML 6.1) events. The Joshua Tree
earthquake was followed on June 28,
1992 by the Landers Earthquake ML
7.3 – the largest earthquake in
historical times in the Mojave Desert
and the largest to strike anywhere in
southern California since the Kern
County Earthquake of 1952.
Offset roads by
Landers Fault
Tower destroyed by
fault motion
Fault rupture
through
Landers
25. • Three hours after the Landers
mainshock, a second
earthquake of ML 6.2 struck
near Big Bear Lake, about
twenty miles west of Landers.
The Big Bear Earthquake was
west of the ECSZ, and on a
left-lateral fault that trends
northeast. Because this
earthquake struck a more
populated area than did
Landers, it was more
destructive. Despite the great
amount of damage there was
no surface rupture in this
quake, nor was there a surface
fault that could be related to
Roof damage to restaurant in Big Bear City
This rather large boulder was dislodged during the Big the mainshock rupture.
Bear Earthquake and landed on Highway 138 blocking
traffic.
26. • Seven years later, on October 16, 1999, a ML 7.1
earthquake was accompanied by surface rupture in the
Marine Corps Training Center between Twentynine
Palms and Barstow. It was named the Hector Mine
Earthquake because there was no populated place close
enough to supply a name. The earthquake ruptured
both the Bullion Fault and the previously unknown
Lavic Lake Fault. Even though the earthquake was
northeast of the lineup of events marking the ECSZ,
the trend of the rupture was the same: north-northwest.
27. Left: Aerial photo
of Lavic Lake Fault
rupture
Above: Offset tire tracks along
Bullion Fault rupture
Right: Inside the
fault