Earth science 9.4
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Paleomagnetism is the study of changes in Earth's magnetic field as shown by patterns of magnetism in rocks formed over time. It supports the theory of plate tectonics by showing how Earth's magnetic field, which can be normal or reversed polarity, is recorded in rocks and how this has changed as continents moved over geologic time. Hot spots are concentrations of heat in the mantle capable of producing magma and rising to Earth's surface, providing additional evidence for plate tectonics.
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Earth Science 9 4
Paleomagnetism is the study of changes in Earth's magnetic field as shown by patterns of magnetism in rocks formed over time. It supports the theory of plate tectonics by showing that rocks can have normal or reverse magnetic polarity depending on their age and location, indicating movements of tectonic plates over Earth's surface throughout geological history. Evidence like paleomagnetism, seafloor spreading, earthquake patterns, and hot spots all provide support for the theory of plate tectonics.
Mark the Boundaries Act 2
This document discusses plate tectonics and describes the distribution of active volcanoes, earthquake epicenters, and major mountain belts. It explains that places where most earthquakes and volcanic activity occur mark the boundaries between lithospheric plates. As the plates slowly move relative to each other along these boundaries, geologic events like earthquakes, volcanoes, and mountain formation take place. The objectives are to describe this distribution and determine the scientific basis for dividing the lithospheric plates.
PLATE TECTONICS(GRADE10SCIENCE 1STQUARTER MODULE1)
This tacklesabout locating epicenter,3 typesof plate boundaries hotspot.
A ppt presentation for module 1 in 1st quarter in grade 10sciencein the Philippines.
Feel free tomessage mefor any corrections/suggestions forimprovement.
ÖNCEL AKADEMİ: SOLID EARTH GEOPHYSICS
The document discusses several topics related to oceanic lithosphere and plate tectonics. It describes how subducting oceanic plates can be delineated by inclined zones of seismicity, known as Wadati-Benioff zones, that studies show are colder than the surrounding mantle. It also explains how oceanic crust and lithosphere thicken away from mid-ocean ridges due to isostatic compensation, and how oceanic plates move away from ridges and eventually descend at subduction zones as they reheat. Heat drives plate tectonics as the cooling oceanic lithosphere forms strong plates that move and interact at plate boundaries.
Let’s mark the boundaries
This document discusses plate tectonics and describes the distribution of active volcanoes, earthquake epicenters, and major mountain belts. It notes that places where most earthquakes originate and some mountains and volcanoes formed mark the boundaries of lithospheric plates. Each plate slowly moves relative to the others, causing geological events like volcanoes and earthquakes to occur along their boundaries. Plates are large pieces of the upper Earth that move as single units above the mantle, and important processes happen at their margins such as mountain building, quakes, and volcanic eruptions.
Split and separate!
The document contains answers to questions about plate tectonics and the movement of lithospheric plates. It explains that the stripes on the diagram represent rocks with normal and reverse magnetic polarities. The middle split represents the mid-ocean ridge, where seafloor spreading occurs and new crust is formed. The mid-ocean ridge is where the forces that push the lithospheric plates originate from. Magma rises from below the crust at the ridge and hardens to form new seafloor that moves away from the ridge. Subduction occurs at the side slits. The Earth does not get larger as plates move apart because as new crust is created at ridges, old crust is destroyed elsewhere.
Seafloor magnetic polarity 2
A transform boundary is a plate boundary where plates slide past each other laterally. The San Andreas Fault in California is the closest transform boundary to us.
Earth's magnetic field periodically reverses polarity over geological time. When this happens, newly formed igneous rocks record the change, with magnetic minerals aligning to the new field orientation. By examining the alternating normal and reversed polarity bands in sea floor sediments on both sides of mid-ocean ridges, scientists can see evidence of past magnetic field reversals that provide information about plate tectonic movements over time.
Module 1 intro
- Earthquakes are caused by the theory of plate tectonics. They frequently occur at plate boundaries. The focus is the point of rupture underground, while the epicenter is the point on the surface directly above the focus.
- Seismology is the study of earthquakes, seismologists study earthquakes, and seismographs are used to measure and record seismic waves. There are different types of seismic waves.
- Volcanoes form from accumulations of erupted materials from vents in the Earth's surface. They consist of a vent, crater, and volcanic cone built up of layers of lava, ash, and rock. The main types are composite, shield, and cinder cones.
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Earth Science 9 4
Paleomagnetism is the study of changes in Earth's magnetic field as shown by patterns of magnetism in rocks formed over time. It supports the theory of plate tectonics by showing that rocks can have normal or reverse magnetic polarity depending on their age and location, indicating movements of tectonic plates over Earth's surface throughout geological history. Evidence like paleomagnetism, seafloor spreading, earthquake patterns, and hot spots all provide support for the theory of plate tectonics.
Mark the Boundaries Act 2
This document discusses plate tectonics and describes the distribution of active volcanoes, earthquake epicenters, and major mountain belts. It explains that places where most earthquakes and volcanic activity occur mark the boundaries between lithospheric plates. As the plates slowly move relative to each other along these boundaries, geologic events like earthquakes, volcanoes, and mountain formation take place. The objectives are to describe this distribution and determine the scientific basis for dividing the lithospheric plates.
PLATE TECTONICS(GRADE10SCIENCE 1STQUARTER MODULE1)
This tacklesabout locating epicenter,3 typesof plate boundaries hotspot.
A ppt presentation for module 1 in 1st quarter in grade 10sciencein the Philippines.
Feel free tomessage mefor any corrections/suggestions forimprovement.
ÖNCEL AKADEMİ: SOLID EARTH GEOPHYSICS
The document discusses several topics related to oceanic lithosphere and plate tectonics. It describes how subducting oceanic plates can be delineated by inclined zones of seismicity, known as Wadati-Benioff zones, that studies show are colder than the surrounding mantle. It also explains how oceanic crust and lithosphere thicken away from mid-ocean ridges due to isostatic compensation, and how oceanic plates move away from ridges and eventually descend at subduction zones as they reheat. Heat drives plate tectonics as the cooling oceanic lithosphere forms strong plates that move and interact at plate boundaries.
Let’s mark the boundaries
This document discusses plate tectonics and describes the distribution of active volcanoes, earthquake epicenters, and major mountain belts. It notes that places where most earthquakes originate and some mountains and volcanoes formed mark the boundaries of lithospheric plates. Each plate slowly moves relative to the others, causing geological events like volcanoes and earthquakes to occur along their boundaries. Plates are large pieces of the upper Earth that move as single units above the mantle, and important processes happen at their margins such as mountain building, quakes, and volcanic eruptions.
Split and separate!
The document contains answers to questions about plate tectonics and the movement of lithospheric plates. It explains that the stripes on the diagram represent rocks with normal and reverse magnetic polarities. The middle split represents the mid-ocean ridge, where seafloor spreading occurs and new crust is formed. The mid-ocean ridge is where the forces that push the lithospheric plates originate from. Magma rises from below the crust at the ridge and hardens to form new seafloor that moves away from the ridge. Subduction occurs at the side slits. The Earth does not get larger as plates move apart because as new crust is created at ridges, old crust is destroyed elsewhere.
Seafloor magnetic polarity 2
A transform boundary is a plate boundary where plates slide past each other laterally. The San Andreas Fault in California is the closest transform boundary to us.
Earth's magnetic field periodically reverses polarity over geological time. When this happens, newly formed igneous rocks record the change, with magnetic minerals aligning to the new field orientation. By examining the alternating normal and reversed polarity bands in sea floor sediments on both sides of mid-ocean ridges, scientists can see evidence of past magnetic field reversals that provide information about plate tectonic movements over time.
Module 1 intro
- Earthquakes are caused by the theory of plate tectonics. They frequently occur at plate boundaries. The focus is the point of rupture underground, while the epicenter is the point on the surface directly above the focus.
- Seismology is the study of earthquakes, seismologists study earthquakes, and seismographs are used to measure and record seismic waves. There are different types of seismic waves.
- Volcanoes form from accumulations of erupted materials from vents in the Earth's surface. They consist of a vent, crater, and volcanic cone built up of layers of lava, ash, and rock. The main types are composite, shield, and cinder cones.
Plate Tectonics
Wegener first proposed continental drift in the early 20th century, suggesting that continents were once joined together in a supercontinent called Pangaea. While evidence like matching coastlines and fossil distributions supported drift, Wegener could not explain the forces driving plate motions. In the 1960s, the new theory of plate tectonics emerged, proposing that Earth's outer layer is broken into rigid plates that move over the mantle. At plate boundaries, plates diverge, converge, or slide past each other, creating geological features like mid-ocean ridges and subduction zones. Paleomagnetic and seafloor spreading evidence confirmed plate tectonics, and mantle convection is now understood to be the primary driver of
Plate Tectonics
The document summarizes key concepts about plate tectonics from a textbook chapter. It discusses:
1) Evidence that initially supported continental drift theory including matching continents, fossil matches, and rock structures.
2) The development of the plate tectonics theory to explain continental movement, with rigid plates that move over Earth's mantle.
3) The three main types of plate boundaries - divergent where plates move apart, convergent where they move together, and transform where they grind past each other.
Sea floor spreading
Scientists in the 1950s used sonar to map the mid-ocean ridge and discovered it was not flat but contained underwater mountains. This discovery led them to research what the ridge was and how it formed. Evidence from molten rock samples, magnetic stripes in the ocean crust, and the ages of rocks drilled from the ocean floor supported Harry Hess' theory from 1960 of sea-floor spreading, where new crust forms at mid-ocean ridges and spreads outward over time.
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The document discusses the theories of continental drift, seafloor spreading, and plate tectonics. It provides details on the original proponent of continental drift theory, Alfred Wegener, in 1915. It also outlines various geological, climatic, and biological evidence that supports continental drift. The document then discusses the sea floor spreading theory proposed by Harry Hess in the 1960s, which helped explain continental drift. It notes evidence that the ocean floor becomes progressively younger near mid-ocean ridges. Finally, it describes how the theories of continental drift and sea floor spreading were combined into the comprehensive theory of plate tectonics.
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This document discusses tectonic landscapes and the distribution of earthquakes and volcanoes around the world. It aims to describe the global distribution of these geological events and name specific eruptions and quakes. Students will learn about the inner and outer core, mantle, and crust of the Earth by making an egg model. The formation of the Earth's continents through plate tectonics is also examined, with evidence for continental drift presented. Real-time maps of current earthquakes and volcanic activity are provided.
Evidence of Sea-Floor Spreading
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.
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In this presentation,it is taking about plate tectonics and sea floor spreading with suitable diagrams respectively. During and just after World War II, the technological improvement to submarines led to an improvement in underwater navigation and surveying that revealed many intriguing underwater features. The most important of these were immense, continuous chains of volcanic mountains running along the ocean basins. These features are now termed mid-ocean ridges or more accurately, oceanic ridge systems.
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The document summarizes plate tectonics and the structure and dynamics of the Earth. It describes the four main layers of the Earth and explains that plate tectonics involves the constant motion of tectonic plates due to convection currents in the mantle. It provides evidence that supported the theory of continental drift and discusses how sea floor spreading and subduction at trenches cause the plates to move over time.
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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.
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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.
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Wegener first proposed continental drift in the early 20th century, suggesting that continents were once joined together in a supercontinent called Pangaea. While evidence like matching coastlines and fossil distributions supported drift, Wegener could not explain the forces driving plate motions. In the 1960s, the new theory of plate tectonics emerged, proposing that Earth's outer layer is broken into rigid plates that move over the mantle. At plate boundaries, plates diverge, converge, or slide past each other, creating geological features like mid-ocean ridges and subduction zones. Paleomagnetic and seafloor spreading evidence confirmed plate tectonics, and mantle convection is now understood to be the primary driver of
Plate Tectonics
The document summarizes key concepts about plate tectonics from a textbook chapter. It discusses:
1) Evidence that initially supported continental drift theory including matching continents, fossil matches, and rock structures.
2) The development of the plate tectonics theory to explain continental movement, with rigid plates that move over Earth's mantle.
3) The three main types of plate boundaries - divergent where plates move apart, convergent where they move together, and transform where they grind past each other.
Sea floor spreading
Scientists in the 1950s used sonar to map the mid-ocean ridge and discovered it was not flat but contained underwater mountains. This discovery led them to research what the ridge was and how it formed. Evidence from molten rock samples, magnetic stripes in the ocean crust, and the ages of rocks drilled from the ocean floor supported Harry Hess' theory from 1960 of sea-floor spreading, where new crust forms at mid-ocean ridges and spreads outward over time.
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Continental drift &and sea floor spreading
The document discusses the theories of continental drift, seafloor spreading, and plate tectonics. It provides details on the original proponent of continental drift theory, Alfred Wegener, in 1915. It also outlines various geological, climatic, and biological evidence that supports continental drift. The document then discusses the sea floor spreading theory proposed by Harry Hess in the 1960s, which helped explain continental drift. It notes evidence that the ocean floor becomes progressively younger near mid-ocean ridges. Finally, it describes how the theories of continental drift and sea floor spreading were combined into the comprehensive theory of plate tectonics.
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This document discusses tectonic landscapes and the distribution of earthquakes and volcanoes around the world. It aims to describe the global distribution of these geological events and name specific eruptions and quakes. Students will learn about the inner and outer core, mantle, and crust of the Earth by making an egg model. The formation of the Earth's continents through plate tectonics is also examined, with evidence for continental drift presented. Real-time maps of current earthquakes and volcanic activity are provided.
Evidence of Sea-Floor Spreading
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.
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In this presentation,it is taking about plate tectonics and sea floor spreading with suitable diagrams respectively. During and just after World War II, the technological improvement to submarines led to an improvement in underwater navigation and surveying that revealed many intriguing underwater features. The most important of these were immense, continuous chains of volcanic mountains running along the ocean basins. These features are now termed mid-ocean ridges or more accurately, oceanic ridge systems.
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Platetectonics theory
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.
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This document provides an overview of plate tectonics and the evidence that supports the theory. It discusses how early scientists like Alfred Wegener proposed that continents move over time (continental drift). Wegener noticed matching land features and fossil evidence between continents. Later, Harry Hess confirmed Wegener's ideas by discovering that new crust forms at mid-ocean ridges, providing evidence of sea-floor spreading as plates move apart. Convection currents in the mantle caused by heat from the Earth's core are now understood to drive the movement of tectonic plates.
Plate tectonic Theory
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.
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Grade 10 Earth Science 1st quater : Plate tectonics
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Behavior is defined as the way an organism reacts to internal or external changes. There are different types of behaviors including innate behaviors which appear fully formed the first time without experience, and learned behaviors which develop through experience. The major types of learning are habituation, classical conditioning, operant conditioning, and insight learning, each involving different processes of forming associations between stimuli and responses.
D:\Students Documents\Biology 1 1
Science is an organized way of using evidence from observations and experiments to build knowledge about the natural world and make predictions. It involves making observations to gather data, making inferences based on prior knowledge, developing hypotheses as possible explanations, and using those explanations to understand nature and forecast future events. The overall goal of science is to investigate, explain, and predict natural phenomena.
Biology 9 2
The Krebs cycle breaks down pyruvic acid into carbon dioxide through a series of energy-extracting reactions. The electron transport chain then uses the high-energy electrons produced in the Krebs cycle to convert ADP into ATP. The Krebs cycle and electron transport chain are key stages of aerobic cellular respiration that extract energy from organic molecules through oxidative reactions requiring oxygen.
Earth Science 10
Intraplate volcanism occurs within tectonic plates away from boundaries and results from hotter than normal mantle material called mantle plumes rising toward the surface. Plate motions provide mechanisms for mantle rock melting which generates magma at boundaries, while intraplate volcanism specifically occurs when mantle plumes independently rise from deeper in the mantle.
Earth Science 9 2
The theory of plate tectonics proposes that Earth's outer shell consists of individual, rigid plates that interact at boundaries, causing earthquakes, volcanoes, and mountains. There are three types of plate boundaries: divergent boundaries where plates move apart like oceanic ridges; convergent boundaries where plates move together; and transform boundaries where plates slide past each other without creating or destroying lithosphere. According to the theory, the lithosphere consists of plates that are continually shifting and changing shape at these boundary interactions.
Earth science 25.2
The document summarizes the evolution of stars from their birth as protostars through their death as black holes or neutron stars. It describes protostars, supernovae, white dwarfs, neutron stars, pulsars, and black holes. Key concepts are that nuclear fusion begins in protostars once the core reaches 10 million K, all stars eventually run out of fuel and collapse due to gravity, and the sun will progress from nebula to main sequence star to red giant to planetary nebula to white dwarf and finally black dwarf.
Biology 13
Scientists use genetic engineering techniques like restriction enzymes, gel electrophoresis, and polymerase chain reaction to manipulate DNA. Restriction enzymes cut DNA at specific sequences. Gel electrophoresis separates DNA fragments by size. Polymerase chain reaction allows scientists to copy specific genes. Together these methods allow scientists to extract, cut, analyze, and replicate DNA to produce recombinant DNA and study and change genetic code.
Earth Science 19 2
This document defines and describes various atmospheric circulation patterns and pressure systems:
- Cyclones are low pressure centers with counterclockwise winds in the Northern Hemisphere. Anticyclones are high pressure centers with clockwise winds.
- Trade winds blow eastward on both sides of subtropical high pressure belts. Westerlies blow west to east between the subtropical highs and polar regions.
- Polar easterlies blow from polar highs toward subpolar lows but are not as persistent as trade winds. The polar front separates cold polar and warm tropical air masses.
- Monsoons are seasonal wind reversals over large continents like Asia, blowing from land to sea in winter and sea to land in
20 5
Funguslike protists absorb nutrients from dead and decaying matter like fungi, but contain centrioles and lack chitin cell walls. Slime molds play key roles in recycling organic material. Oomycetes thrive on dead organic matter in water and some parasitize plants, with all funguslike protists obtaining nutrients from non-living sources essential to decomposition.
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Biology 26.1
This document defines key terms related to the animal kingdom, including invertebrates, vertebrates, feedback inhibition, blastula, protostomes, deuterostomes, radial symmetry, bilateral symmetry, and more. It describes animals as multicellular, eukaryotic heterotrophs and outlines their essential functions of feeding, respiration, circulation, excretion, response, movement, and reproduction. Complex animals are noted to have high cell specialization, internal organization, bilateral symmetry, a head with sense organs, and a body cavity.
Biology 26.2
Sponges contain specialized cells like choanocytes that use flagella to move water through the sponge for feeding, respiration, circulation, and excretion. They have structures like spicules made of calcium carbonate or silica that form their skeleton, and archaeocytes that produce these spicules. Sponges reproduce through internal fertilization and larval stages, and some can form protective gemmules during unfavorable conditions.
Biology 22.5
Angiosperms are flowering plants that reproduce sexually through flowers. Flowers contain ovaries that surround and protect seeds. Angiosperms are divided into monocots and dicots based on whether their seeds have one cotyledon (monocot) or two cotyledons (dicot). Flowering plants can also be annuals, biennials, or perennials depending on whether their life cycle is one, two, or more than two years.
Earth science 13.1
The document discusses Precambrian time from 4.56 billion years ago until the Cambrian period over 4 billion years later. It describes shields as flat expanses of ancient metamorphic rock within continental interiors. Stromatolites are layered mounds formed from algae trapping sediment and calcium carbonate. Earth's original atmosphere lacked oxygen but primitive organisms evolved photosynthesis which began releasing oxygen into the atmosphere around 2.5 billion years ago.
Earth science 13.4
The Cenozoic Era saw the rise of mammals as the dominant land animal, replacing reptiles. Flowering plants known as angiosperms also became the dominant land plant over gymnosperms. Major geological events like mountain building, volcanism, and earthquakes occurred in western regions due to plate tectonics during this era. Mammals were better adapted than reptiles for more active lifestyles through bearing live young and maintaining steady body temperatures.
Earth science 13.2
The Paleozoic Era saw an explosion of life, as the continents of Gondwana and Laurasia formed most of the southern and northern portions of the supercontinent Pangea. During the Cambrian, Ordovician, and Silurian periods, life was restricted to the seas surrounding Gondwana, which contained the continents of present-day South America, Africa, Australia, Antarctica, and parts of Asia. By the end of the Paleozoic Era, around 400 million years ago, all continents had fused into the single landmass of Pangea, and plants first began moving from waterside habitats onto land.
Earth science 13.3
The Mesozoic era was the Age of Reptiles, where reptiles like dinosaurs quickly became the dominant land animals due to developing shelled eggs. Gymnosperms also dominated as the prominent plant during this time. A major geological event was the breakup of the supercontinent Pangea. Many reptile groups went extinct at the end of the Mesozoic era.
Earth science 9.1
Continental drift is the hypothesis that the continents were once joined together and have since drifted apart. Originally proposed by Wegener, it suggests the continents were part of a supercontinent called Pangaea approximately 200 million years ago that has since broken apart, moving the landmasses into their current positions. Fossil and rock evidence support this idea, including matching fossil organisms and mountain ranges found on separate continents today that indicate the continents were once joined.
Earth science 8.2
This document discusses seismograms and the different types of seismic waves that are recorded, including P waves, S waves, and surface waves. It explains that seismograms amplify and electronically record ground motion from earthquakes, allowing scientists to determine the epicenter location using travel time graphs from multiple seismographs. The document also covers historical intensity and magnitude scales used to describe earthquake size and introduces moment magnitude as the most widely used scale today because it estimates the energy released.
Biology 28 2 groups of arthropods
This document defines and describes key anatomical terms used to classify groups of arthropods. It discusses the cephalothorax, thorax, and abdomen found in crustaceans, as well as specific structures like the carapace, mandibles, chelipeds, swimmerets, chelicerae, pedipalps, and spinnerets. It concludes with three key concepts: arthropods are classified by body segments and appendages, especially mouthparts; crustaceans typically have two antennae, two or three body sections, and mandibles; and chelicerates have chelicerae mouthparts and two body sections, with nearly all having four pairs of walking legs.
Biology 2.4
Chemical reactions involve reactants being converted into products through breaking and forming chemical bonds, requiring a minimum amount of energy called the activation energy. Catalysts like enzymes speed up reactions by lowering this activation energy, with enzymes being protein catalysts that facilitate substrate reactions within cells.
Earth science 12.3
This document discusses radiometric dating and how it is used to determine the absolute ages of rocks and minerals. It explains key concepts such as radioactivity, half-life, and how comparing ratios of radioactive isotopes like carbon-14 and carbon-12 can be used to calculate radiocarbon dates for samples. Radiometric dating relies on the fact that radioactive isotopes decay at a constant rate and comparing the amounts of parent and daughter isotopes allows the age of a sample to be estimated.
Earth science 9.1
Continental drift is the hypothesis that the continents were once joined together and have since drifted apart. Originally proposed by Wegener, it suggests the continents were part of a supercontinent called Pangaea approximately 200 million years ago that has since broken apart, moving the landmasses into their current positions. Fossil and rock evidence support this idea, including matching fossil organisms and mountain ranges found on separate continents today that indicate the continents were once joined.
Earth science 7.3
Wind shapes landscapes through processes like deflation, desert pavement formation, and loess and dune deposition. Deflation is the lifting and removal of loose material by wind. Desert pavement is a layer of coarse pebbles created when wind removes finer material. Loess deposits are windblown silt deposits that form blanket-like layers, while dunes are ridges of wind-deposited sand that can vary in shape depending on wind and vegetation factors.
Earth science 7.2
Much of the weathered debris in deserts comes from mechanical weathering like alluvial fans formed where stream slopes abruptly decrease. While chemical weathering is less common, over long periods clays and thin soils can form. Desert streams are ephemeral, only flowing after rain, and often drying up before reaching oceans due to evaporation and soil infiltration. Most desert erosion comes from running water, though wind also erodes deserts, water does the most erosional work.
Earth science 7.1
Glaciers are large masses of ice that originate on land from compacted snow and move due to gravity. During an ice age, large ice sheets form on continents and flow outward, carving U-shaped valleys and depositing unsorted sediment called till. Valley glaciers are smaller glaciers confined to mountain valleys that flow due to plastic deformation and basal sliding between the ice and bedrock.
Earth science 6.3
Groundwater exists below the surface in the saturated zone where all spaces between rock and sediment are filled with water. The water table marks the top of this zone, and groundwater moves slowly through porous and permeable materials. Springs form where the water table intersects the surface, and overuse or contamination can threaten groundwater supplies in some areas. Karst regions have irregular terrain with sinkholes caused by erosion of soluble rock by groundwater in caverns below the water table.
Earth science 6.2
This document defines key terms related to streams and their processes, including bed load, capacity, alluvium, delta, natural levee, floodplain, flood, drainage basin, divide. It also describes concepts such as how streams erode and deposit sediment according to flow velocities, and how flooding occurs and can be mitigated. The overall work of streams is to shape the landscape through erosion, transportation, and deposition of sediment within drainage basins.
Earth science 6.1
The document discusses key concepts about running water and the water cycle. It defines terms like infiltration, transpiration, gradient, stream channel, discharge, tributary, base level, and meander. It explains that water constantly circulates among the oceans, atmosphere, geosphere, and biosphere in the water cycle. Balance in the cycle means annual precipitation equals evaporation globally. A stream's ability to erode and transport materials depends on its velocity, while gradient decreases and discharge increases from headwaters to the mouth.
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Earth science 9.4
- 1. Testing Plate Tectonics 9.4
- 2. Paleomagnetism • The study of changes in Earth’s magnetic field, as shown by patterns of magnetism in rocks that have formed overtime.
- 3. Normal Polarity • A magnetic field that is the same as that which exists in the present.
- 4. Reverse Polarity • A magnetic field opposite to that which exists at present.
- 5. Hot Spot • A concentration of heat in the mantle capable of producing magma; which rises to Earth’s surface.
- 6. Key Concept • What evidence supports the theory of plate tectonics? –Continental drift, seafloor spreading, palemagnetism, earthquake patterns, ocean drilling, and ocean hot spots.
- 7. Key Concept • How does paleomagnetism support the theory of plate tectonics? –By showing how Earth’s magnetic field affects rocks overtime.