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0004 Understand the components and evolution of the Earth system

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0004
Understand the components and evolution of the Earth system.

The 3 basic rock types. Ask GeoMan... What are the 3 basic types of rocks? Just as any person can be put into one of two main categories of human being, all rocks can be put into one of three fundamentally different types of rocks. They are as follows: Igneous Rocks Igneous rocks are crystalline solids which form directly from the cooling of magma. This is an exothermic process (it loses heat) and involves a phase change from the liquid to the solid state. Sedimentary Rocks In most places on the surface, the igneous rocks which make up the majority of the crust are covered by a thin veneer of loose sediment, and the rock which is made as layers of this debris get compacted and cemented together.

Clastic: your basic sedimentary rock. Click here for more on sedimentary processes and rocks (RCC). Metamorphic Rocks The metamorphics get their name from "meta" (change) and "morph" (form). Click here to ask GeoMan a question Return to Ask GeoMan's Index of Questions Return to GeoMan's Home Page. The 3 basic rock types. Radioactive Dating. The technique of comparing the abundance ratio of a radioactive isotope to a reference isotope to determine the age of a material is called radioactive dating. Many isotopes have been studied, probing a wide range of time scales. The isotope 14C, a radioactive form of carbon, is produced in the upper atmosphere by neutrons striking 14N nuclei. The neutron is captured by the 14N nucleus and knocks out a proton. Thus, we have a different element, 14C.

Once living things die, they no longer can exchange carbon with the environment. Perhaps you have heard of Ice Man, a man living in the Alps who died and was entombed in glacial ice until recently when the ice moved and melted. The boat of a pharaoh was discovered in a sealed crypt and reassembled in a museum near the pyramids (see Fig. 13-4). Other methods of dating are used for non-living things. 40K decays with a half-life of 1.3 ´ 109 years to 40Ar which can be trapped in rocks.

Evolution and the Fossil Record by John Pojeta, Jr. and Dale A. Springer. Dating the Fossil Record (Previous Page || Next Page) The study of the sequence of occurrence of fossils in rocks, biostratigraphy, reveals the relative time order in which organisms lived. Although this relative time scale indicates that one layer of rock is younger or older than another, it does not pinpoint the age of a fossil or rock in years.

The discovery of radioactivity late in the 19th century enabled scientists to develop techniques for accurately determining the ages of fossils, rocks, and events in Earth's history in the distant past. For example, through isotopic dating we've learned that Cambrian fossils are about 540-500 million years old, that the oldest known fossils are found in rocks that are about 3.8 billion years old, and that planet Earth is about 4.6 billion years old. About 90 chemical elements occur naturally in the Earth. To help in the identification and classification of elements, scientists have assigned an atomic number to each kind of atom.

TropicalConnections_GeologicalTimeWithMajorEvolutionaryEventsInFossilRecord_KruczynskiFletcher.pdf. Geologic and Biological Timeline of the Earth. Astronomical and geological evidence indicates that the Universe is approximately 13,700 million years old, and our solar system is about 4,567 million years old. Earth's Moon formed 4,450 million years ago, just 50 million years after the Earth's formation. Because the composition of the rocks retrieved from the Moon by the Apollo missions is very similar to rocks from the Earth, it is thought that the Moon formed as a result of a collision between the young Earth and a Mars-sized body, sometimes called Theia, which accreted at a Lagrangian point 60° ahead or behind the Earth. A cataclysmic meteorite bombardment (the Late Heavy Bombardment) of the Moon and the Earth 3,900 million years ago is thought to have been caused by impacts of planetesimals which were originally beyond the Earth, but whose orbits were destabilized by the migration of Jupiter and Saturn during the formation of the solar system.

Simplified model of the formation of the Moon (my = millions of years) Glossary. ThePlanetWeLiveOn-Chapter4.pdf. Formation of Fault Block Mountains. Fault block mountains are distinguished by great sheer rock faces. These form when enormous underground pressure forces a whole rock mass to break away from another. The line at which this break takes place is called a fault. On one side of this break the rocks rise; on the other side they sink down. An example of this process, however on a much smaller scale, was the 1906 San Francisco earthquake, when a series of tremors dislocated the rock strata by as much as 21 feet along the fault line that ran right through the city. Some of the most spectacular mountain scenery anywhere are the great rock walls of the Sierra Nevada which are actually the sides of huge tilted fault blocks.

Because of these characteristics the Sierras rise fairly gently from the West, only about 200 feet per mile. HomeDisclaimer. Geology Cafe.com. Behavior of the Lithosphere: (Crust and Upper Mantle) Subdivisions used in geologic discussions relating to "Plate Tectonics Theory" (discussed below) include: lithosphere—the rocky outer portion of the Earth, consist of the crust and upper mantle (about the upper 60 miles below the Earth's surface).

It is the solid "brittle" zone of the earth where earthquakes occur. asthenosphere—the upper portion of the mantle underlying the lithosphere where heat and pressure is great enough for materials to flow "like plastic. " This movement is driven by the heat derived from within the deeper parts of the mantle and core that cause materials to flow by gravitational convection (see Figure 5-5). Gravitational convection works as follows—Adding heat causes materials (solid and molten) to expand, loose density, and rise; whereas cooling material shrinks and increases in density, and sinks. Ocean crust—part of Earth's lithosphere that underlies ocean basins. The "Continental Drift Hypothesis" Spreading center. Rift valley. A rift valley forms where the Earth’s crust, or outermost layer, is spreading or splitting apart. This kind of valley is often narrow, with steep sides and a flat floor.

Rift valleys are also called grabens, which means “ditch” in German. While there is no official distinction between a graben and a rift valley, a graben usually describes a small rift valley. Rift valleys differ from river valleys and glacial valleys because they are created by tectonic activity and not by the process of erosion. Rift valleys are created by plate tectonics. Many rift valleys have been found underwater, along the large ridges that run throughout the ocean.

This occurs along the northern crest of the Mid-Atlantic Ridge, where the North American plate and the Eurasian plate are splitting apart. In the Pacific Ocean, the East Pacific Rise has created rift valleys where the Pacific plate is separating from the North American plate, Riviera plate, Cocos plate, Nazca plate, and Antarctic plate. Great Rift Valley. 3 types of volcano structures.

Scientists describe 10 types of volcanoes but 3 types of volcano structures are most often discussed. The 3 main types of volcano structures are listed below with brief descriptions. 3 types of volcano structures Source : Volcanoes (A Firefly Guide) isbn 1-55297-683-1 Composite Volcanoes These types of volcanoes are also known as a stratovolcano. It is a cone shaped mountain with steep, smooth, barren slopes often with a single plume of smoke emitted from a single central vent.

In Costa Rica the Poas, Arenal, and Irazu volcanoes are examples of composite volcanoes. Shield Volcanoes A large volcanic structure with long gentle slopes built up almost entirely from fluid lava flows. The shape of this type of volcano is more like a dome than a tall cone. The largest active volcano in the world is a shield volcano in Hawaii named Mauna Loa.

They are the simplest of volcano structures and are prevalent in Western North America and elsewhere in the world. More volcano links Costa Rica volcano links. Volcanodiagram. 3. Journey Through Earth. In the style of Jules Verne’s book Journey to the Center of the Earth, take your students on a walk, using sidewalk chalk to mark the boundaries between the different ... SummaryIn the style of Jules Verne’s book Journey to the Center of the Earth, take your students on a walk, using sidewalk chalk to mark the boundaries between the different layers inside our planet. After you pass through each layer, tell your students about the layer of the Earth they just traveled through. This lesson was developed by Eric Muller of the Exploratorium Teachers’ Institute. Here you will find a student handout for taking notes during the walk, a teacher cheat sheet and some assessment ideas.

Earth's Layers: Layers not drawn to scale. Image courtesy of Jeremy Kemp.VocabularyInner coreOuter coreMantleLithosphereCrust Time10 min introduction35-40 min walk GroupingWhole class Materials SettingSidewalk around 2-3 city blocks (640+ meter loop) Teacher BackgroundThe earth is composed of many distinct layers. Plate Tectonics Vocabulary flashcards. Tectonic Plates. The edges of these plates, where they move against each other, are sites of intense geologic activity, such as earthquakes, volcanoes, and mountain building. Plate tectonics is a relatively new theory and it wasn't until the 1960's that Geologists, with the help of ocean surveys, began to understand what goes on beneath our feet. Where is the Evidence for Plate Tectonics? It is hard to imagine that these great big solid slabs of rock could wander around the globe.

Scientists needed a clue as to how the continents drifted. The discovery of the chain of mountains that lie under the oceans was the clue that they were waiting for. Click here for the Scotland story Picture the following in your mind: You have a nine piece jigsaw (now there's a challenge). What do you think will happen to the puzzle? Now let's think back to our plates being created at the mid-ocean ridges, it seems to be a good idea but if this is the only type of plate movement then the world would get bigger and bigger. Plate Tectonics.

Ask GeoMan... What is plate tectonics? There are really only two processes: one that forms the physical earth, and another that beats up the surface and tears it apart through weathering and erosion. The formational process is called tectonics, and is manifested to those of us living on earth by earthquakes, volcanos, and mountain building in general. The earth is really just a sphere of liquid rock (magma) which has cooled to the solid state where exposed to the coldness of space. We call this cold and rigid outer shell the crust, and it is actually rather thin in comparison to the overall diameter of our planet. Because of the heat and pressure beneath the surface, this crust is constantly being subjected to stresses which break it up. Plates are moving towards each other, and the crust of the earth is shortened. GeoMan's RCC Continental Drift and Plate Tectonics section GeoMan's Grants Pass High School Geology Home Page AskGeoMan: Plate Boundary Summary. The 3 basic rock types.

Observing the Three Types of Rocks. The name of a rock reflects certain characteristics. For example, obsidian will resemble glass and scoria will usually be dark red with holes. Rock names also refer to a texture. For example granite will have interlocking minerals and sandstone will have a gritty, sandy feel. Young children need to experience these characteristics before they can internalize the name of a rock.

They need to describe and compare the characteristics, as they learn the rock’s name. IGNEOUS OBSIDIAN - Also known as volcanic glass. Types of Rocks: The Three Major Rock Groups. Did you know that lava is molten rock that reaches the earth's surface? Furthermore, did you know that rocks exist in three general forms: igneous, sedimentary and metamorphic? This lesson describes these rock types and examples of each. Explore our library of over 10,000 lessons You now have full access to our lessons and courses, watch the lesson now or keep exploring. You've watched a video!

Now you are officially smarter, check out the next video or take the quiz to keep learning. You took a quiz! You just finished your first lesson. You're making great progress. You've learned so much, but only scratched the surface. Getting a perfect score on a quiz is how you gain course progress. You're getting the hang of this! Look how far you've come! Keep clicking that 'next lesson' button whenever you finish a lesson and its quiz. You're 25% of the way through this course! Two days in a row, nice!

Rock Cycle: Igneous, Sedimentary, and Metamorphic rocks. In this lesson, we will discuss the three main types of rocks and how they are formed. The lesson also gives an introduction into how matter locked in rocks can be cycled through the earth. Explore our library of over 10,000 lessons You now have full access to our lessons and courses, watch the lesson now or keep exploring. You've watched a video! Now you are officially smarter, check out the next video or take the quiz to keep learning. You took a quiz! Getting a perfect score on a quiz is how you gain course progress. You just finished your first lesson. You're making great progress. You've learned so much, but only scratched the surface. Getting a perfect score on a quiz is how you gain course progress. You're getting the hang of this! Look how far you've come! Keep clicking that 'next lesson' button whenever you finish a lesson and its quiz.

You're 25% of the way through this course! Two days in a row, nice! Geology Kitchen: 3 Types of Rocks - Ms. Shon's Spectacular Science. Earth Structure, Materials, Systems, & Cycles. Geology Cafe.com. Essential concepts of chemistry related to earth materials Basic concepts of chemistry are essential to understanding the physical and chemical properties of earth materials (minerals, rocks, organic matter, etc.). The chemical characteristics of earth materials are reflect the environments how and where they are formed, they also determine their potential fate when exposed to chemical changes. For instance, rocks and minerals formed deep underground may not be stable in the surface environment where they are exposed to water, air, temperature changes, and other physical and chemical conditions.

All matter is made up of atoms, and atoms are made up of atomic particles (electrons, protons, and neutrons - see Figure 2-5). A chemical element is a pure chemical substance consisting of one type of atom distinguished by its atomic number, which is the number of protons in its nucleus. Common examples of elements are iron, copper, silver, gold, hydrogen, carbon, nitrogen, and oxygen.