The document discusses how paleomagnetic evidence can provide support for continental drift theory.
1) Rocks become magnetized as they solidify according to the Earth's magnetic field orientation at the time. Measurements of ancient rocks show alternating magnetic polarities, indicating the magnetic field has reversed many times in the past.
2) Apparent polar wander curves, which plot the changing location of the magnetic poles relative to different continents over time, do not align when continents are separated. However, the curves align when the continents are configured as part of an assembled supercontinent, providing evidence they have drifted apart.
This document discusses various geological structures including folds, faults, and joints. It defines folds as bent rock layers, and describes key parts of folds such as the crest, trough, limbs, and axial plane. It also categorizes different types of folds based on their symmetry, plunge, and other characteristics. The document then defines faults as fractures with displacement, and explains fault terminology including the fault plane, footwall, hanging wall, and types of movement. Finally, it briefly introduces joints as fractures found in rocks.
A map is a representation of Earth's surface that shows spatial relationships between objects by depicting their distance, direction, and size relative to each other on a flat surface. Maps convey information about a specific area and indicate its position relative to other parts of Earth. A geological map specifically shows the distribution and types of rocks and soils in an area. Geological maps are important tools used by geologists to understand Earth's structure and history, locate resources, and identify natural hazards.
This summary mind map covers various topics in physical geography including earth's internal structure, tectonic plates and forces, responses to tectonic hazards, landforms and phenomena, coastal features and processes, elements of weather and climate, climate change, and extreme weather events. Some key points include:
- Earth's structure includes the core, mantle, crust, asthenosphere and lithosphere. Tectonic forces include convection currents and slab-pull forces.
- Plate boundaries include transform, convergent and divergent boundaries. Responses to hazards involve preparation, short-term emergency response, and long-term recovery and infrastructure improvement.
- Coastal landforms are created by erosion and deposition processes driven
1. Minerals are naturally occurring, inorganic crystalline solids with a definite chemical composition.
2. Minerals form repeating patterns within crystals that can be cubic, tetragonal, hexagonal, orthorhombic, monoclinic, or triclinic.
3. Physical properties of minerals include color, streak, luster, hardness, cleavage, and fracture.
The document discusses several topics related to mineral economics, including:
1. Limiting factors in mining such as minerals being immobile and depleting over time, requiring companies to find new deposits as production costs may rise.
2. A country's economic and social development reflects the discovery, exploration, and depletion of its mineral resources over different periods.
3. For a country to control its mining destiny, it should have economic policies addressing financing, marketing, and valuation of mines and mineral deposits.
1) Geophysical surveys have been using measurements of the Earth's magnetic field for nearly 500 years since Gilbert showed that the Earth behaves like a large magnet.
2) Gravity and magnetic surveying methods are similar in that they both measure naturally occurring fields (potential fields), can use identical physical representations like magnetic monopoles, and have similar data acquisition and interpretation.
3) However, magnetic surveying also has differences from gravity - magnetic susceptibility of rocks can vary more than density, magnetism can be attractive or repulsive unlike gravity, magnetic sources always occur in pairs unlike gravity, and the magnetic field is time-dependent unlike gravity.
Quartz is a mineral composed mainly of silicon dioxide that is the second most abundant mineral on Earth. It can be found in various forms of rock all over the world. A large quartz vein was discovered in Gwinnett County, Georgia in 2008. Quartz has a variety of uses including as a component of computer chips and circuit boards due to its piezoelectric properties, and as decorative gemstones.
This document provides an overview of igneous rocks and their classification. It discusses that igneous rocks crystallize from magmas, which can be felsic, intermediate, or mafic depending on their silica content. Igneous rocks are classified based on mineral content using diagrams like the QAPF diagram. The ordering of mineral crystallization from cooling magma is explained by Bowen's reaction series. Common igneous minerals like feldspars, pyroxenes, amphiboles, and micas are described in terms of their composition, properties, and where they occur in the crystallization sequence. Phase diagrams provide additional insight into crystallization beyond Bowen's series.
This document discusses various geological structures including folds, faults, and joints. It defines folds as bent rock layers, and describes key parts of folds such as the crest, trough, limbs, and axial plane. It also categorizes different types of folds based on their symmetry, plunge, and other characteristics. The document then defines faults as fractures with displacement, and explains fault terminology including the fault plane, footwall, hanging wall, and types of movement. Finally, it briefly introduces joints as fractures found in rocks.
A map is a representation of Earth's surface that shows spatial relationships between objects by depicting their distance, direction, and size relative to each other on a flat surface. Maps convey information about a specific area and indicate its position relative to other parts of Earth. A geological map specifically shows the distribution and types of rocks and soils in an area. Geological maps are important tools used by geologists to understand Earth's structure and history, locate resources, and identify natural hazards.
This summary mind map covers various topics in physical geography including earth's internal structure, tectonic plates and forces, responses to tectonic hazards, landforms and phenomena, coastal features and processes, elements of weather and climate, climate change, and extreme weather events. Some key points include:
- Earth's structure includes the core, mantle, crust, asthenosphere and lithosphere. Tectonic forces include convection currents and slab-pull forces.
- Plate boundaries include transform, convergent and divergent boundaries. Responses to hazards involve preparation, short-term emergency response, and long-term recovery and infrastructure improvement.
- Coastal landforms are created by erosion and deposition processes driven
1. Minerals are naturally occurring, inorganic crystalline solids with a definite chemical composition.
2. Minerals form repeating patterns within crystals that can be cubic, tetragonal, hexagonal, orthorhombic, monoclinic, or triclinic.
3. Physical properties of minerals include color, streak, luster, hardness, cleavage, and fracture.
The document discusses several topics related to mineral economics, including:
1. Limiting factors in mining such as minerals being immobile and depleting over time, requiring companies to find new deposits as production costs may rise.
2. A country's economic and social development reflects the discovery, exploration, and depletion of its mineral resources over different periods.
3. For a country to control its mining destiny, it should have economic policies addressing financing, marketing, and valuation of mines and mineral deposits.
1) Geophysical surveys have been using measurements of the Earth's magnetic field for nearly 500 years since Gilbert showed that the Earth behaves like a large magnet.
2) Gravity and magnetic surveying methods are similar in that they both measure naturally occurring fields (potential fields), can use identical physical representations like magnetic monopoles, and have similar data acquisition and interpretation.
3) However, magnetic surveying also has differences from gravity - magnetic susceptibility of rocks can vary more than density, magnetism can be attractive or repulsive unlike gravity, magnetic sources always occur in pairs unlike gravity, and the magnetic field is time-dependent unlike gravity.
Quartz is a mineral composed mainly of silicon dioxide that is the second most abundant mineral on Earth. It can be found in various forms of rock all over the world. A large quartz vein was discovered in Gwinnett County, Georgia in 2008. Quartz has a variety of uses including as a component of computer chips and circuit boards due to its piezoelectric properties, and as decorative gemstones.
This document provides an overview of igneous rocks and their classification. It discusses that igneous rocks crystallize from magmas, which can be felsic, intermediate, or mafic depending on their silica content. Igneous rocks are classified based on mineral content using diagrams like the QAPF diagram. The ordering of mineral crystallization from cooling magma is explained by Bowen's reaction series. Common igneous minerals like feldspars, pyroxenes, amphiboles, and micas are described in terms of their composition, properties, and where they occur in the crystallization sequence. Phase diagrams provide additional insight into crystallization beyond Bowen's series.
Guidelines for lithological, structural and geomorphic interpretationNikhil Sherekar
The document discusses guidelines for lithological, structural, and geomorphic interpretation from aerial photographs. It explains that aerial photos can be used to interpret rock types based on differences in topography, slopes, drainage, geometry, and other features. Structural features like dipping beds, folded structures, faults, and joints can also be identified from aerial photos. Lastly, geomorphic interpretation from aerial photos allows detailed mapping and analysis of landforms, drainage patterns, and other terrain features to study geomorphology.
Geodynamics studies mantle convection and plate tectonics to understand phenomena like seafloor spreading and mountain building. It provides fundamentals for how the solid Earth works as a heat engine. Early theorists like Wegener and Du Toit proposed continental drift to explain geological similarities between continents. In the 1960s, seafloor mapping and studies of magnetic pole positions in rocks supported plate tectonics, where convection in the mantle drives the motion of rigid tectonic plates. This theory was accepted when it provided a unifying framework and mechanism to explain observations of geology and geophysics.
This document provides information on minerals, rocks, and their properties. It defines minerals as naturally occurring solid materials with a defined chemical composition and internal structure. The most common elements in Earth's crust are oxygen, silicon, aluminum, iron, calcium, sodium, and potassium. Minerals are divided into silicate and non-silicate groups. Key silicate minerals include quartz, feldspar, mica, amphibole, pyroxene, olivine, and garnet. Non-silicates include carbonates, oxides, sulfides, phosphates, and native elements. Physical properties used to identify minerals include color, streak, luster, hardness, crystal shape, cleavage, fracture, and specific
The document describes an activity where students are broken into groups to learn about different tectonic plate boundaries. Students first watch a presentation on plate tectonics. They are then divided into home groups and assigned to research one of three boundary types: convergent, divergent, or transform. After researching, students return to their home groups to teach each other about the boundary they learned.
1. Harry Hess proposed the theory of seafloor spreading in 1962, which provided evidence that Wegener's theory of continental drift was correct. Hess theorized that new ocean crust is formed at mid-ocean ridges through volcanic eruptions and then spreads outwards, pushing older crust farther away.
2. Evidence for seafloor spreading includes rock formations only possible from cooled lava, magnetic stripe patterns in ocean crust recording reversals of Earth's magnetic field, and drilling samples showing younger rock nearer to ridges.
3. Seafloor spreading is driven by convection currents in the Earth's mantle; subduction zones allow parts of ocean crust to sink back into the mantle and regulate ocean size.
The Integration of Geospatial Technologies: GIS and GPS Lindsey Landolfi
This document discusses the integration of Geographic Information Systems (GIS) and Global Positioning Systems (GPS). It describes how GIS and GPS technologies can be combined in various ways, including data-focused integration where GPS data is collected in the field and later imported into a GIS database, and technology-focused integration where GPS capabilities are fully embedded within a GIS application. The benefits of integration include improved data accuracy and increased productivity. Examples of integrated GIS and GPS applications in use by government agencies are provided.
The document discusses plate tectonics and the evidence that supports the theory. It explains that the Earth's crust is broken into plates that move relative to each other. There are three main types of plate boundaries: divergent, convergent, and transform. Evidence for plate tectonics includes the locations of earthquakes and volcanoes along plate boundaries, as well as the movement of continents over geologic time as described by Alfred Wegener's theory of continental drift.
1. Geology is the science that studies the physical structure and composition of the Earth, as well as the processes that act on it.
2. Geology provides knowledge about construction materials like stones and clay that are important for civil engineering projects. It also helps understand natural geological processes like erosion that impact projects.
3. Geology is important for understanding groundwater resources and interpreting drilling data for projects like dams and bridges to ensure stable foundations.
Rock samples near mid-ocean ridges provided evidence for sea floor spreading. The youngest rocks were found near the ridges, with older rocks located farther away, showing that new crust was being created at the ridges over time. Additional evidence came from magnetic striping patterns in the rocks, which recorded changes in Earth's magnetic field during the formation of new ocean crust along the ridges. Hydrothermal vents at the ridges also indicated that magma chambers must be close to the surface in order to heat the water emerging from the vents.
The document discusses plate tectonic theory and provides evidence for plate tectonics. It explains that the lithosphere is broken into plates that move atop the asthenosphere due to convection currents in the mantle. There are three types of plate boundaries - divergent where plates move apart, convergent where they move together, and transform where they slide past each other. Plate tectonics helps explain geological phenomena like volcanoes, earthquakes, and mountain building.
Continental Drift Theory proposed that the continents were once joined together in a single landmass called Pangaea. Evidence for this theory included:
1) The matching coastline edges of continents like Africa and South America, and geological features that lined up across continents.
2) Similar fossil species found in matching geological formations along coastlines now separated by oceans.
3) Identical aged rock formations and tillite deposits along the separated coastlines, indicating they were once attached.
This theory was initially rejected due to the lack of an explained physical mechanism for continental drift, but was later supported by the development of plate tectonic theory.
This document discusses petrology, which is the branch of geology that studies rocks and the conditions under which they form. It describes the three main classes of rocks - igneous, sedimentary, and metamorphic - and their key characteristics. Igneous rocks form from cooling magma, either deep underground as plutonic rocks or at the surface as volcanic rocks. Sedimentary rocks are formed from the lithification of sediments. Metamorphic rocks form from the alteration of existing rocks through heat, pressure, and chemically active fluids in the Earth's crust.
El documento proporciona 3 pasos para crear un slidecast: 1) Subir la presentación de diapositivas a Slide, 2) Añadir el archivo MP3, 3) Sincronizar las diapositivas con el archivo de audio MP3.
Gadhavi Sunilkumar Shankarbhai is an experienced senior marketing leader with over 20 years of experience in sales, marketing, business development, and operations management in the cable and wire industry. He is currently the Senior Manager of Marketing at KEI Industries Ltd. in Ahmedabad, where he has helped increase annual revenue and profits to INR 11 crores. He has a strong track record of developing innovative marketing strategies and business plans, implementing sales programs, managing distributors and dealers, and acquiring new business opportunities. He holds an MBA in Marketing and a Bachelor's degree in Instrumentation and Control Engineering.
Diplomação dos políticos eleitos em 2016 nas cidades Apuiarés, General Sampai...zedalegnas
O documento discute a importância da educação para o desenvolvimento econômico e social de um país. A educação é essencial para promover a inovação, a produtividade e o crescimento econômico sustentável a longo prazo. Investimentos em educação também melhoram os padrões de vida da população e promovem uma sociedade mais igualitária e justa.
This document proposes a model for harnessing wind energy from trains to power electrical components. It involves mounting horizontal axis wind turbines on the rooftops of train cars. The turbines would charge batteries that power lights, fans, and other devices inside the train. Mathematical models are presented to calculate the expected power output from turbines on a train moving at 60 km/hr. It is estimated that 27 turbines installed on one car could generate 483 Watts, enough to power all interior lights and still have 123 Watts remaining to power additional items like fans or mobile chargers. Harnessing wind energy in this way could provide an auxiliary power source to complement existing battery systems.
Praveen Kumar Raju C has over 9 years of experience implementing and supporting Oracle E-Business Suite applications. He has extensive experience with Oracle HRMS, Payroll, Financials and other modules. Some of his project experiences include serving as the technical lead for implementations at the Ministry of Foreign Affairs in Saudi Arabia and Al Rajhi Bank. He is proficient in forms, reports, workflows and other technical components of Oracle E-Business Suite.
Dipesh Sangtani is seeking an operations management position that allows for continued growth. He has 5 years of experience in operations management, trade finance, foreign exchange, and client relationship management. Currently an officer at Bank of Baroda, he is responsible for managing trade finance facilities and processing import and export documentation. He also has experience as an analyst providing research to financial institutions in Europe.
Infographie - Repreneurs, cédants : c'est quoi la garantie d'actif et de pass...FIDAQUITAINE
La garantie d’actif ou de passif, est un engagement du vendeur à indemniser l’acheteur si l’actif diminue ou si le passif augmente après la cession, mais portant sur des événements antérieurs à cette cession.
Let's Get 'Wild': 6 Adventure Activities To Do In & Around MaharahstraPankaj Sabnani
If you stay in Maharashtra and suffer from boring weekends, it's perhaps an indication that you need some adventure in your life. This presentation talks about 6 different adventure activities you can experience all through the year!
Guidelines for lithological, structural and geomorphic interpretationNikhil Sherekar
The document discusses guidelines for lithological, structural, and geomorphic interpretation from aerial photographs. It explains that aerial photos can be used to interpret rock types based on differences in topography, slopes, drainage, geometry, and other features. Structural features like dipping beds, folded structures, faults, and joints can also be identified from aerial photos. Lastly, geomorphic interpretation from aerial photos allows detailed mapping and analysis of landforms, drainage patterns, and other terrain features to study geomorphology.
Geodynamics studies mantle convection and plate tectonics to understand phenomena like seafloor spreading and mountain building. It provides fundamentals for how the solid Earth works as a heat engine. Early theorists like Wegener and Du Toit proposed continental drift to explain geological similarities between continents. In the 1960s, seafloor mapping and studies of magnetic pole positions in rocks supported plate tectonics, where convection in the mantle drives the motion of rigid tectonic plates. This theory was accepted when it provided a unifying framework and mechanism to explain observations of geology and geophysics.
This document provides information on minerals, rocks, and their properties. It defines minerals as naturally occurring solid materials with a defined chemical composition and internal structure. The most common elements in Earth's crust are oxygen, silicon, aluminum, iron, calcium, sodium, and potassium. Minerals are divided into silicate and non-silicate groups. Key silicate minerals include quartz, feldspar, mica, amphibole, pyroxene, olivine, and garnet. Non-silicates include carbonates, oxides, sulfides, phosphates, and native elements. Physical properties used to identify minerals include color, streak, luster, hardness, crystal shape, cleavage, fracture, and specific
The document describes an activity where students are broken into groups to learn about different tectonic plate boundaries. Students first watch a presentation on plate tectonics. They are then divided into home groups and assigned to research one of three boundary types: convergent, divergent, or transform. After researching, students return to their home groups to teach each other about the boundary they learned.
1. Harry Hess proposed the theory of seafloor spreading in 1962, which provided evidence that Wegener's theory of continental drift was correct. Hess theorized that new ocean crust is formed at mid-ocean ridges through volcanic eruptions and then spreads outwards, pushing older crust farther away.
2. Evidence for seafloor spreading includes rock formations only possible from cooled lava, magnetic stripe patterns in ocean crust recording reversals of Earth's magnetic field, and drilling samples showing younger rock nearer to ridges.
3. Seafloor spreading is driven by convection currents in the Earth's mantle; subduction zones allow parts of ocean crust to sink back into the mantle and regulate ocean size.
The Integration of Geospatial Technologies: GIS and GPS Lindsey Landolfi
This document discusses the integration of Geographic Information Systems (GIS) and Global Positioning Systems (GPS). It describes how GIS and GPS technologies can be combined in various ways, including data-focused integration where GPS data is collected in the field and later imported into a GIS database, and technology-focused integration where GPS capabilities are fully embedded within a GIS application. The benefits of integration include improved data accuracy and increased productivity. Examples of integrated GIS and GPS applications in use by government agencies are provided.
The document discusses plate tectonics and the evidence that supports the theory. It explains that the Earth's crust is broken into plates that move relative to each other. There are three main types of plate boundaries: divergent, convergent, and transform. Evidence for plate tectonics includes the locations of earthquakes and volcanoes along plate boundaries, as well as the movement of continents over geologic time as described by Alfred Wegener's theory of continental drift.
1. Geology is the science that studies the physical structure and composition of the Earth, as well as the processes that act on it.
2. Geology provides knowledge about construction materials like stones and clay that are important for civil engineering projects. It also helps understand natural geological processes like erosion that impact projects.
3. Geology is important for understanding groundwater resources and interpreting drilling data for projects like dams and bridges to ensure stable foundations.
Rock samples near mid-ocean ridges provided evidence for sea floor spreading. The youngest rocks were found near the ridges, with older rocks located farther away, showing that new crust was being created at the ridges over time. Additional evidence came from magnetic striping patterns in the rocks, which recorded changes in Earth's magnetic field during the formation of new ocean crust along the ridges. Hydrothermal vents at the ridges also indicated that magma chambers must be close to the surface in order to heat the water emerging from the vents.
The document discusses plate tectonic theory and provides evidence for plate tectonics. It explains that the lithosphere is broken into plates that move atop the asthenosphere due to convection currents in the mantle. There are three types of plate boundaries - divergent where plates move apart, convergent where they move together, and transform where they slide past each other. Plate tectonics helps explain geological phenomena like volcanoes, earthquakes, and mountain building.
Continental Drift Theory proposed that the continents were once joined together in a single landmass called Pangaea. Evidence for this theory included:
1) The matching coastline edges of continents like Africa and South America, and geological features that lined up across continents.
2) Similar fossil species found in matching geological formations along coastlines now separated by oceans.
3) Identical aged rock formations and tillite deposits along the separated coastlines, indicating they were once attached.
This theory was initially rejected due to the lack of an explained physical mechanism for continental drift, but was later supported by the development of plate tectonic theory.
This document discusses petrology, which is the branch of geology that studies rocks and the conditions under which they form. It describes the three main classes of rocks - igneous, sedimentary, and metamorphic - and their key characteristics. Igneous rocks form from cooling magma, either deep underground as plutonic rocks or at the surface as volcanic rocks. Sedimentary rocks are formed from the lithification of sediments. Metamorphic rocks form from the alteration of existing rocks through heat, pressure, and chemically active fluids in the Earth's crust.
El documento proporciona 3 pasos para crear un slidecast: 1) Subir la presentación de diapositivas a Slide, 2) Añadir el archivo MP3, 3) Sincronizar las diapositivas con el archivo de audio MP3.
Gadhavi Sunilkumar Shankarbhai is an experienced senior marketing leader with over 20 years of experience in sales, marketing, business development, and operations management in the cable and wire industry. He is currently the Senior Manager of Marketing at KEI Industries Ltd. in Ahmedabad, where he has helped increase annual revenue and profits to INR 11 crores. He has a strong track record of developing innovative marketing strategies and business plans, implementing sales programs, managing distributors and dealers, and acquiring new business opportunities. He holds an MBA in Marketing and a Bachelor's degree in Instrumentation and Control Engineering.
Diplomação dos políticos eleitos em 2016 nas cidades Apuiarés, General Sampai...zedalegnas
O documento discute a importância da educação para o desenvolvimento econômico e social de um país. A educação é essencial para promover a inovação, a produtividade e o crescimento econômico sustentável a longo prazo. Investimentos em educação também melhoram os padrões de vida da população e promovem uma sociedade mais igualitária e justa.
This document proposes a model for harnessing wind energy from trains to power electrical components. It involves mounting horizontal axis wind turbines on the rooftops of train cars. The turbines would charge batteries that power lights, fans, and other devices inside the train. Mathematical models are presented to calculate the expected power output from turbines on a train moving at 60 km/hr. It is estimated that 27 turbines installed on one car could generate 483 Watts, enough to power all interior lights and still have 123 Watts remaining to power additional items like fans or mobile chargers. Harnessing wind energy in this way could provide an auxiliary power source to complement existing battery systems.
Praveen Kumar Raju C has over 9 years of experience implementing and supporting Oracle E-Business Suite applications. He has extensive experience with Oracle HRMS, Payroll, Financials and other modules. Some of his project experiences include serving as the technical lead for implementations at the Ministry of Foreign Affairs in Saudi Arabia and Al Rajhi Bank. He is proficient in forms, reports, workflows and other technical components of Oracle E-Business Suite.
Dipesh Sangtani is seeking an operations management position that allows for continued growth. He has 5 years of experience in operations management, trade finance, foreign exchange, and client relationship management. Currently an officer at Bank of Baroda, he is responsible for managing trade finance facilities and processing import and export documentation. He also has experience as an analyst providing research to financial institutions in Europe.
Infographie - Repreneurs, cédants : c'est quoi la garantie d'actif et de pass...FIDAQUITAINE
La garantie d’actif ou de passif, est un engagement du vendeur à indemniser l’acheteur si l’actif diminue ou si le passif augmente après la cession, mais portant sur des événements antérieurs à cette cession.
Let's Get 'Wild': 6 Adventure Activities To Do In & Around MaharahstraPankaj Sabnani
If you stay in Maharashtra and suffer from boring weekends, it's perhaps an indication that you need some adventure in your life. This presentation talks about 6 different adventure activities you can experience all through the year!
This document provides an overview of Mormonism as a competing religious worldview. It discusses key aspects of Mormon theology such as Joseph Smith's founding of the religion, the Book of Mormon, and distinctive Mormon teachings like humans becoming gods, polygamy, and Jesus visiting North America. The document also examines criticisms of Mormonism regarding historical and archaeological issues with its founding claims and compares it to a Christian worldview based on Jesus' statements about the exclusive truth and narrow path to salvation.
The uppermost layer of soil consists of humus, sand, mud and rock particles. Humus consists of decayed plants and animal remains. Weathering is the breaking down of rocks into smaller pieces through physical or chemical processes. Factors like climate, parent rock type and land slope determine the type of soil formed. The major soil layers are topsoil, subsoil and bedrock.
Informe actividades 2015- Comisión Cuenca Amecameca y CompañíaComisionCuenca
Este documento presenta un informe de actividades de 2014 de la Comisión de Cuenca de los Ríos Amecameca y la Compañía. Detalla numerosas reuniones y eventos realizados por la Comisión con autoridades gubernamentales, organizaciones civiles y comunidades locales relacionadas con la gestión del agua y proyectos de saneamiento en la región. También incluye fotografías de algunas de estas actividades y reuniones.
Vijay Tripathi is applying for the position of Senior Manager Marketing. He has over 25 years of experience in marketing roles of increasing responsibility. He has a proven track record of successful marketing initiatives that have driven customer loyalty and business development. Vijay emphasizes his strong communication and relationship building skills, which he believes are among his greatest strengths. He looks forward to discussing how he can further advance the visibility of the company.
Genesis' mystery of God creating Our Universe is explored through lens of Computer-like Universe Tools verse by verse in the Bible's Genesis 1 & 2 Accounts with thought provoking questions.
* What is the nature of time?
* Was light created when God said "Let there be light?"
* How was the earth lighted with day & night before the sun, moon, and stars were created?
* What scientific possibilities did God illustrate in the creation account?
Universe Tools Paradigm
Universe Schematic
Literal Creator Days
Thought Experiment
Challenging statements & questions & explanations
* What are Literal Creator Days?
* How does this compare to other viewpoints?
* When do science and God's Word fit together?
Learn more at http://creationopia.wordpress.com and http://bibleopia.wordpress.com
anatomy of the lower extremity veins, CVI , ambulatory venous hypertension, varicose veins , clinical examination and performance of various tests of the varicose veins
1) O documento discute a igreja mórmon, incluindo sua fundação por Joseph Smith em 1830 e suas principais crenças como a existência de profetas modernos e revelações adicionais.
2) Os mórmons têm quatro escrituras sagradas além da Bíblia, incluindo o Livro de Mórmon.
3) O documento fornece refutações bíblicas de algumas das crenças mórmons como a natureza de Deus e a inspiração da Bíblia.
The document discusses geomagnetism and Earth's magnetic field. It begins with an introduction that provides background on magnetic fields and the objective to show how Earth's magnetic field affects geomagnetism. It then describes Earth's magnetic field, factors that influence it like temperature and the dynamo effect in the core. Evidence for the magnetic field includes interactions with solar winds seen in the magnetosphere and auroras. The conclusion notes debate around whether a magnetic field reversal may currently be underway and uncertainties around the field's future behavior.
The Earth's magnetic field is generated by electrical currents in the liquid outer core. The magnetic field traps charged particles from the solar wind in the Van Allen radiation belts. Rocks record the magnetic field at the time of formation, allowing scientists to study how the magnetic poles have reversed in the past. The magnetic field shields the Earth from solar wind and cosmic rays.
The document discusses the origin of Earth's magnetic field. It states that Earth's magnetic field is generated in the liquid outer core by electrical currents from convection and the planet's rotation. This dynamo process produces the main geomagnetic field. The magnetic field also has sources from the crust and ionosphere. The document then discusses methods for observing and measuring the geomagnetic field.
This document discusses plate tectonics and plate boundaries. It defines plates as rigid lithospheric slabs and plate tectonics as the process of plate motions. There are six major and 20 minor identified plates that move over the asthenosphere. Plate boundaries are where tectonic activity occurs and are divided into three types: divergent boundaries where plates move apart, convergent boundaries where plates move towards each other, and transform boundaries where plates move sideways relative to each other. Sea-floor spreading and paleomagnetism provide evidence for plate tectonics theory.
The document discusses the Earth's magnetic field and how it is generated by convection currents in the outer core. Rocks become magnetized as they form, recording the orientation and strength of the magnetic field at that time. Studying the magnetic signatures in rocks of different eras has revealed that the magnetic poles have reversed positions many times in the past and have also shifted locations gradually, providing evidence that continents have moved over time. The Earth's magnetic field is prone to periodic reversals over thousands of years, with the last one occurring around 800,000 years ago. The field has declined in strength in recent centuries, suggesting another reversal of the poles may be due in around 1500 years.
1) The document discusses plate tectonics, describing the different types of plates (oceanic and continental), how there are 6 major and 20 minor tectonic plates, and the three types of plate boundaries - divergent, convergent, and transform.
2) It provides details on sea floor spreading and paleomagnetism as evidence for plate tectonics, describing how sea floor spreading occurs at mid-ocean ridges and how paleomagnetism records the magnetic properties in older rocks.
3) Plate tectonics theory postulates that the lithosphere is made up of these rigid tectonic plates that move over Earth's surface, and that geological activities occur at plate boundaries.
£££ Jack Oughton - Planetary Science Presentation 03 - A Brief Guide To Terre...Jack Oughton
The document discusses the Earth's magnetic field and magnetic polar reversals. It explains that the field is generated by convection currents in the Earth's liquid outer core, known as the geodynamo. The magnetic poles have changed positions many times throughout history, as evidenced by the magnetic orientations locked in ancient lava and rock. While a reversal takes thousands of years, the magnetic field does not disappear completely during this process. The current field protects life on Earth from solar radiation.
Magnetic reversal is a process where the Earth's magnetic poles switch places. The magnetic field reverses approximately every 400,000 years, as shown by magnetic stripes in volcanic rocks on the seafloor. These reversals are caused by changes in the flow of the Earth's liquid outer core. Studying the magnetic patterns in seafloor rocks provides evidence for the theory of seafloor spreading, as it allows scientists to construct a record of past magnetic polarity.
This document summarizes key concepts about magnetism and magnetic fields from a university physics textbook:
1) It describes how magnetic resonance imaging (MRI) uses magnetic fields to visualize soft tissues, and discusses the earth's magnetic field and how compasses work based on it.
2) It explains how magnetic fields are created by moving charges and currents, and exert forces on other moving charges. Magnetic poles always come in pairs, unlike electric charges which can be isolated.
3) It discusses applications of magnetic fields like particle accelerators, magnetic bottles for plasma containment, and the Van Allen radiation belts around Earth.
This is my magnetism presentation.
Copyrighted images have been removed and replaced with a URL or a suitable replacement image from Wikimedia Commons.
The document discusses the dynamo theory of the Earth's magnetism. It proposes that electric currents produced by the movement of liquid iron in the Earth's outer core generate the planet's magnetic field. Convection currents provide the energy needed to sustain the magnetic field over geological timescales. Paleomagnetic studies of fossil magnetism in rocks support the idea that the Earth's magnetic poles have reversed polarity multiple times in the past, consistent with the dynamo theory.
Magnetic reversal occurs when the Earth's magnetic poles flip so that the North Pole becomes the South Pole and vice versa. Scientists can detect magnetic reversals by studying the magnetic minerals in volcanic rocks on the seafloor. As the rocks cool from lava, the magnetic minerals align with the Earth's magnetic field at that time. The pattern of alternating magnetic stripes on opposite sides of seafloor spreading ridges provides evidence that the seafloor is spreading. On average, there are 4-5 magnetic reversals per million years, and the matching magnetic patterns on opposite sides of ridges indicate the seafloor is spreading at a rate of about 2.5 cm per year.
The document discusses the history and theories of Earth's magnetism. It explains that ancient Chinese and Greeks discovered magnetic rocks that pointed north. In 1600, William Gilbert proposed that Earth itself acts as a giant spherical magnet based on his experiments. This led to the question of what causes Earth's magnetism. Early theories proposed Earth's core was a permanent magnet, but this was disproven. Later, the dynamo theory emerged, attributing magnetism to electric currents in Earth's liquid outer core driven by convection. Paleomagnetic studies of fossil magnets in rocks support that Earth's magnetic poles have reversed many times.
Sir William Gilbert hypothesized in the late 1500s that Earth acts as a giant magnet, explaining why compasses point north. While Earth's core is too hot to be the source of magnetism, the circulation of molten material in the core is related to Earth's magnetic field. Earth's magnetic poles are located in northern Canada and Antarctica, differing from the geographic poles. Earth's magnetic field can magnetize ferromagnetic materials like iron over long periods of time.
1. The document summarizes a presentation on magnetic survey methods given on May 21, 2020. It discusses concepts like magnetic susceptibility of rocks, elements that make up Earth's magnetic field like the core and mantle, and how magnetic polarity reversals are recorded in rocks.
2. Key factors that control magnetic susceptibility of rocks are magnetic minerals like olivine and magnetite. Susceptibility can also depend on mineral grain alignment. Magnetic fabrics provide information on rock composition and formation processes.
3. Earth has layers of increasing density, from less dense continental crust to denser mantle and core. The outer core generates convection currents that power the magnetic field, and the inner solid core rotates to produce it.
- The document discusses the topic of magnetism, including bar magnets, the Earth's magnetism, and magnetic properties of materials.
- It describes how William Gilbert established several postulates about magnetism in 1600, including that the Earth acts as a giant bar magnet and a bar magnet will point north-south when suspended.
- The document also discusses how the magnetic field lines of a bar magnet resemble those of a solenoid, suggesting bar magnets can be thought of as many circulating currents.
The document summarizes Earth's structure and composition. It describes that Earth has distinct layers including the crust, mantle, and core. The crust and upper mantle form Earth's lithosphere which is separated into tectonic plates. The mantle circulates heat via convection currents which drive plate tectonics. Earth's inner core is solid iron while the outer core is liquid nickel-iron alloy. Earth's magnetic field is generated by convection currents in the outer core which protects life from solar radiation.
Earth’s magnetic field, called the geomagnetic field, is the magnetic field that extends from the earth’s interior out into space. When the solar wind, a stream of charged particles emanating from the sun, interacts with the earth’s magnetic field, most of them are trapped in the Van Allen radiation belt and protects the earth from the harmful charged particles and cosmic rays. The earth exhibits like a bar magnet in which the North geographic pole actually represents the South pole of the earth’s magnetic field, and conversely the South geographic pole corresponds to the North pole of the earth’s magnetic field. The scientists described the cause of the earth’s magnetism that the magnetic field is generated by electric currents due to the motion of convection currents from a mixture of molten iron and nickel in the earth’s outer core these convection currents are caused by heat escaping from the core, a natural process called a geodynamo. The circulating ions that are highly conducting in the outer core of the earth result in the formation of the current loops. These current loops are the reason behind the formation of the magnetic field. Then paleomagnetism is developed to measure the magnetism in rocks that was induced by the earth’s magnetic field. In this paper, cause of the earth’s magnetism is enlightened in a new way. The existence of molten iron and nickel in the earth’s outer core is incorrect because of this high temperature evolving in the outer core of the earth, the materials in other layers also melt. Actually the cause of the earth’s magnetism is the interaction of electric fields electric current induced by the solar wind coronal discharge and the movement of the earth including both rotations about its own axis and the sun as per Faraday and Lenz’s laws of electromagnetic induction. For this cause, all other planets and the satellites e.g., moon in the solar system are having magnetic field which obstructs the maximum high energy particles from the sun solar wind to discharge on their surfaces. Dr. Pijush Kanti Bhattacharjee "Identification Cause of Earth’s Magnetism" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-6 | Issue-3 , April 2022, URL: https://www.ijtsrd.com/papers/ijtsrd49534.pdf Paper URL: https://www.ijtsrd.com/engineering/electrical-engineering/49534/identification-cause-of-earth’s-magnetism/dr-pijush-kanti-bhattacharjee
Similar to How can Earth's magnetic field be used to give evidence for plate tectonics? (20)
How can Earth's magnetic field be used to give evidence for plate tectonics?
1. How Can Earthʼs Magnetic Field be
Used to Give Evidence for
Continental Drift?
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2. Table of Contents
Magnetic Rocks! 3
1.1 The Origin of Magnetic Properties! 3
1.2 Magnetic Domains! 3
Earthʼs Magnetic Field! 4
2.1 Origin of the Main Field! 4
2.2 Periodic Reversal of the Main Field! 5
2.3 Secular Variation! 7
Paleomagnetic Evidence for Plate Tectonics! 8
3.1 Measuring the Magnetic Field in Rocks! 8
3.2 Apparent Polar Wander (APW)! 8
3.3 Effects of Polar Reversal, Secular Change and Westward Drift! 9
Glossary! 10
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3. Magnetic Rocks
1.1 The Origin of Magnetic Properties
Many minerals throughout the Earthʼs crust contain Iron, which is well know for itʼs magnetic properties.
Ferromagnetic minerals such as magnetite, Fe3O4, are given magnetic properties by the magnetic dipole
moment of an electron. The magnetic dipole moment of an electron comes from the fundamental property an
electron has, called spin, it causes the electron to act like a small bar magnet12.
The arrangement of electrons in the orbitals surrounding the nucleus will be in such a way as to produce the
lowest possible energy state. What this means is that one electron will occupy each d-orbital before
electrons are paired in the same d-orbital3. Iron ions have partially filled d-orbitals4, which accounts for many
characteristics including ferromagnetism. The unpaired electrons have the same spin and so many of these
electrons across the d-orbitals results in a strong total dipole moment. If the electrons were to pair in the
orbitals the opposite spins would cancel each other out and there would be no net dipole moment from the
atom.
Fig 1.1!! On the left, the actual arrangement of electrons in the 3d orbitals. On the right, if the
! ! electrons were to be paired in the 3d orbitals it would raise the energy of the orbitals as a
! ! result of electron repulsion.
1.2 Magnetic Domains
Minerals are composed of multiple domains, each of which exhibits a crystalline structure. The domains vary
in size but are generally on the nanometre scale. Within each of the domains the magnetic moments are
aligned, however in an unmagnetised mineral the domains are randomly arranged so that their magnetic
moments tend to cancel out and the mineral has no net magnetic field. However the magnetic moments can
be aligned when a magnetic field is applied to the rock as it is heated above itʼs Curie temperature. Under
these conditions the domains which are aligned with the field expand at the expense of surrounding, un-
aligned domains. The magnetisation of rocks occurs naturally during their formation due to the Earthʼs
magnetic field.
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1 Nave, R. Magnetic Dipole Moment, (2004), HyperPhysics, accessed: http://hyperphysics.phy-astr.gsu.edu/
hbase/magnetic/magmom.html ,28.01.2015.
2 Wolfson, R., Essential University Physics, vol. 1, (2007), Pearson Education Inc., Addison Wesley.
3 Lister, T., Renshaw, J., AS Chemistry, 14-19, (2008), Nelson Thornes.
4 Lister, T., Renshaw, J., A2 Chemistry, 214, (2009), Nelson Thornes.
4. Earthʼs Magnetic Field
2.1 Origin of the Main Field
Although the exact processes which produce the Earthʼs magnetic field are still not completely understood, it
has been known since the 1950s that it arrises from the dynamo effect within the core. The dynamo effect
within the Earth is produced by electromagnetic induction within the outer core56. Electromagnetic induction
occures as convection currents cause the electrically conducting molten material of the Earthʼs outer core to
circulate, a charge is built up by friction between the various layers. As the core rotates relative to the Earthʼs
surface, these outward convection currents are organised into loops by the Coriolis effect78 . The circulating
charge forms several current loops. This is why the magnetic field generated by the Earth looks very similar
to that of a current loop.
Fig. 2.1"" The circulating electric currents caused by the Coriolis effect produce a magnetic field
" " around the Earth.
To understand how the current loops in the Earth are produced we first have to look at convection currents
within the outer core. As material close to the core is heated it rises upwards toward the surface where it
spreads out, cools and then sinks back down. This produces loops of moving charge. However, if we
consider the entire Earth we can see that each convection current has a partner current moving in the
opposite direction. This would produce a magnetic field with opposite polarisation and so the Earth would
have no net magnetic field. The current loops described initially are produced by the Coriolis effect.
The Coriolis effect can be observed when we consider different reference frames. If we consider the Earthʼs
reference frame then we observe the traditional convection currents as described above. However if we
consider a reference frame in which the Earth rotates, for example that of the Earthʼs axis, then we see that
the currents raditating outwards and dropping inwards are organised into spirals.
To better understand the Coriolis effect we can imagine a spinning disc, with a marble that moves in a
straight line along the disk from the centre to the edge. Relative to the spinning disc the marble moves in a
straight line, however to an observer watching the spinning disc the marble moves with a curved path. Try to
picture the path of the marble through the observers reference frame as both the disc spins away from the
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5 Bott, Martin H. P., The Interior of the Earth, 169-174, (1971), Edward Arnold.
6 Garland, George D., Introduction to Geophysics, 229-233, (1971), W. B. Saunders Company.
7 Nave, R., The Dynamo Effect, (2006), HyperPhysics, accessed: http://hyperphysics.phy-astr.gsu.edu/
hbase/magnetic/magearth.html 18.01.2015.
8 Vandenbrouck, F., Berthier, L., Gheusi, F., Coriolis Force in Geophysics: an Elementray Introduction and
Examples, 359, (2000), European Journal of Physics 21.4.
5. observer and the marble moves towards the edge of the disc. The line traced on the disc by the marble
moves away from the observer and so at the start of the cycle when the marble is at the centre, it is closer to
the observer than at the end of the cycle when it is furthest from the observer.
Fig 2.2!! The Coriolis effect shown on a spinning disc. On the left - the system from the reference
! ! frame of the viewer. On the right - the system from the reference frame of the disc.
Fig. 2.3"" Without the Coriolis effect the magnetic field would cancel each other out, and the earth
! ! would have no net magnetic field.
2.2 Periodic Reversal of the Main Field
At constructive plate boundaries on the ocean floor, tectonic plates pull apart and molten material from the
mantle rises to the surface. Initially this molten rock is above the Curie temperature, allowing it to be
magnetised by the Earthʼs magnetic field. After rising to the surface it solidfies to form a new sea bed. The
solidifed rock is permanetly magnetised in accordance with the prevailent magnetic field surrounding the
Earth.
By measuring the magnetisation of the rock surrounding these plate margins we find that the ocean floor is
composed of bands with alternating magnetic polarisation, that is to say there are some bands of rock with a
magnetic polarisation opposite to the current field surrounding the Earth. We can discount local anomalies in
the Earthʼs magnetic field as the source for this reversed polarisation because this reversed polarisation is
present along the entire length of the plate bounary.
The real proof of alternating polarisation in the Earthʼs magnetic field lies in the radioactive dating of
reversely polarised mineral samples. Some rocks are capable of self-reversal, and so in order to ammount
substantial proof we must find several examples of reverse polarity which can be dated to the same period.
Fortunately this evidence is available for rocks as old as 360 million years. The time between reversals is
extremely varied, with some periods lasting just 106 years and others lasting up to 107 years910.
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9 Garland, George D., Introduction to Geophysics, 296, (1971), W. B. Saunders Company.
10 Bott, Martin H. P., The Interior of the Earth, 165-168, (1971), Edward Arnold.
6. Fig 2.4!! A time-scale of magnetic field reversion based on a uniform spreading rate in the South
Atlantic Ocean. Periods of polarity in the same direction as the current field are shown in black. Local
magnetic anomalies are shown by dotted lines on the left, the numbers assigned to prominent anomalies are
also shown on the left11.
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11 Heirtzler, J. R., others, Marine Magnetic Anomalies, Geomagnetic Field Reversals and Motions of Ocean
Floor and Continents, 2123, (1968), Journal of Geophysical Research, vol. 73, AMER Geophysical Union.
7. 2.3 Secular Variation
Secular variation describes the changes to the Earthʼs magnetic fields on the time-scale of years. The
changes were first noted when plotting a graph of the declination in major cities, for example London in
154012. The changes occur in the direction, declination and magnitude of the field. In order to measure
secular change, readings must be taken over a period of many days; the greatest change in the field is that
which occurs on a daily basis. An average can then be taken from all these readings so establish how the
magnetic field changes over 10 or more years1314.
Fig 2.5!! Mapping of the changes in the Earthʼs magnetic field in London over 430 years15.
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12 Garland, George D., Introduction to Geophysics, 237, (1971), W. B. Saunders Company.
13 Gass, I. G., Smith, P. J., Wilson, R. C. L., Understanding the Earth, 72-75, (1972), The Artemis Press.
14 Bullard, E. C., The Secular Change in the Earthʼs Magnetic Field, 248-257, (1948), Geophysical
Supplements to the Monthly Notices of the Royal Astronomical Society 5.7.
15 Gass, I. G., Smith, P. J., Wilson, R. C. L., Understanding the Earth, 74, (1972), The Artemis Press.
8. Paleomagnetic Evidence for Plate Tectonics
3.1 Measuring the Magnetic Field in Rocks
The field around a sample of magnetised rock, is the same as that of a bar magnet. In fact, the first magnets
to be discovered were sample of magnetite rock. We know from A-level physics that a changing magnetic
field will produce an EMF in a coil of wire. Thus, by spinning a sample of rock near a coil we can measure
the magnetic field.
A spinner magnetometer works by spinning a magnet between two ends of an iron core, around which a coil
of wire is wound. The iron core is magnetised by the spinning magnet, and the field is directed through the
core, linking the turns in the coil. As the magnet spins and itʼs orientation changes, the direction of the
magnetic field through the core changes producing a change in the magnetic flux, which according to
Faradayʼs law produces an EMF in the coil. By placing a voltmeter across the coil we can measure the EMF
produced.
As the magnet spins with an angular velocity ω, the angle between the field and the core at time t is given by
(1), and so the flux through the coil is then given by (2)
(1)
(2)
According to Faradayʼs law, the EMF is given by the negative rate of change of flux. For a coil with multiple
turns this is (3). So in the case of a magnet spinning in a coil, this is expressed as (4).
(3)
(4)
We then solve the differential, to give the equation (5) which describes a cosinusoidal graph, where the
maximum EMF is (6).
(5)
(6)
By solving equation (6) for the three perpendicular axis of the magnetic sample, we can describe the
magnetic field using three vectors and hence find its direction and magnitude.
3.2 Apparent Polar Wander (APW)
By analysing rock samples and determining the direction of their magnetic field, we can know the postion of
the poles relative to that land mass. To know the latitude we look at the declination of the magnetic field, that
is, the angle at which the field point into or out of the Earthʼs surface. In the Northern Hemishpere rocks have
a negative angle of declination, in the Southern Hemisphere, the reverse. Closer to the poles the magnitude
of the angle is greater than that at the Equator, and at the Equator it is 0°. To know the orientation of the land
mass, we simply align the field lines of the sample with those of the Earth, so that the south pole of the
sample points towards magnetic north1617.
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16 Nield, T., Supercontinent, 197-198, (2007), Granta Publications.
17 Besse, J., Courtillot, V., Revised and synthetic apparent polar wander paths of the African, Eurasian, North
American and Indian plates, and true polar wander since 200 Ma, 4029-4050 (1991) Journal of Geophysical
Research: Solid Earth (1978–2012) 96.B3
9. When we take these measurements for samples from the same land mass but with age differences of
millions of years, we find that the magnetic poles appear to wander. Intially it was though that this was due to
secular change or perhaps an effect, visible only on million year time-scales, linked to pole reversal.
However, when we try to combine the APW maps of different continents, we find that they donʼt fit together. It
appears as though the poles have wandered differently for different land masses. The explanation for this is
that the land masses themselves move. When we overlay the APW maps for now seperate land masses
which are believed to have once been joined as part of the same land mass, we find that the overlap
perfectly. Giving us evidence for continental migration.
Fig 3.1!! APW curves for samples from different continents since the Precambrian period. Solid
curves show where palaeomagnetic data from three or more levels in geological time follow a fairly
consistent sequence. Pole positions are relative to: ■ China; ● Greenland; ▲ Madagascar. Letters refer to PE,
Precambrian; E, Cambrian; O, Ordovician; S, Silurian; D, Devonian; C, Carboniferous; P, Permian; Tr,
Triassic; J, Jurassic; K, Cretaceous; LT, MT, UT, Lower, Middle and Upper Tertiary18.
3.3 Effects of Polar Reversal, Secular Change and Westward Drift
Clearly when trying to map the APW, the effects of Polar Reversal and Secular Change must be taken into
account. Polar reversal is simple to correct for as it is clear when the poles have suddenly switched. Polar
reversal takes just thousands of years, which is a short time in comparison to the hundreds of millions of
years over which the continents drift. The direction of the magnetic field in the samples can simply be
reversed for according to the direction of the magnetic field at the time.
Secular Change is slightly more difficult to correct for, as some of the samples that are used will have come
from rock samples which have cooled past their Curie point over the space of a few years. However, as
Secular Change is largely localised, it is possible to average out the magnetic field over a suitable area to
obtain the average direction of the field.
Westward drift is a fairly simple phenomenon, in which the magnetic field appears to drift Westward over
time. It is explained simply by the fact that the outer core, which produces the Earthʼs magnetic field, rotates
around the Earthʼs axis with a slower angular velocity than the crust, and hence the magnetic field appears
to drift westward relative to the surface. The average rate of drift over all latitudes is 0.18°. This can be
accounted for by simply subtracting the apparent addtional westward drift of the continents and assuming
that the rate of westward drift has remained fairly constant over the time-scale of millions of years1920 .
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18 Deutsch, Ernst, The Rock Magnetic Evidence for Continental Drift, In Continental Drift, ed. Garland, G. D.,
(1966), University of Toronto Press.
19 Garland, George D., Introduction to Geophysics, 240, (1971), W. B. Saunders Company.
20 Livermore, P. W., Hollerbach, R., Jackson, A., Electromagnetically driven westward drift and inner-core
superrotation in Earthʼs core, 15914-15918, (2013), Proceedings of the National Academy of Sciences,
110.40.
10. Glossary
Curie Point or Temperature the temperature at
which the permanent magnetism of a material
becomes induced magnetism.
Declination the angle between magnetic north and
true north.
Dipole Moment see Magnetic Dipole.
Electron Spin the term used to describe the
intrinsic angular momentum of an electron.
Ferromagnetism the manner in which certain
materials, such as iron, form permanent magnets.
Inclination the angle into or out from the Earth at
which the field points.
Magnetic Dipole a north and south pole which
create a magnetic field traditionally flowing from
north to south.
Magnetometer a device for measuring the
magnitude and/or direction of a magnetic field.
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