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Convection Currents
Convection Currents

... Convection currents can occur in liquids or gases. Common examples are in heating water on a stove, or the heat in a room. All you need is a heat source to drive it. ...
Plate Tectonics
Plate Tectonics

... 1. How is heat transferred? 2. What causes convection currents? 3. What causes convection currents in Earths mantle? 4. What is conduction? ...
Earth`s Interior
Earth`s Interior

... The 5 Layers Based on Physical Properties • Earth's physical layers, from the outside to the center, are the lithosphere, the  asthenosphere, the mesosphere, the outer core, and the inner core. • The lithosphere is the cold, brittle layer at Earth's surface. It is a solid layer that  contains all of ...
Presentation
Presentation

... Inferring Why are there areas of overlap? ...
Foundations of Social Studies GEOGRAPHY
Foundations of Social Studies GEOGRAPHY

... External Processes The surface of the earth is subject to forces which change its shape. The most important forces are weathering and erosion. Weathering occurs when rock surfaces decompose and begin to break up. Erosion refers to the actual movement of the broken particles away from their source. T ...
Topic 6 Earth`s Internal Structure and Tectonic Process Geography
Topic 6 Earth`s Internal Structure and Tectonic Process Geography

... Earth's interior is molten, all rocks are of volcanic origin, James Hutton (1795), Theory of the Earth ...
Rapid Changes in Earth`s Surface
Rapid Changes in Earth`s Surface

... Earth’s surface is constantly changing. Wind, water, and ice break down large rocks and move sediments on the surface. It usually takes years for weathering, erosion, and deposition to cause noticeable changes. Some events, though, change Earth’s surface much more quickly. These include volcanic eru ...
Are the oceans spreading at the mid
Are the oceans spreading at the mid

... The next bit is definitely tricky..... NORTH is SOUTH. To explain this we need the think about what gives the Earth its magnetic field. The answer is that the core of the Earth is made up of iron and nickel which are both magnetic, however at 5000°c it's not quite like a bar magnet that we're used t ...
Igneous Rocks
Igneous Rocks

... • Volcanic rocks are igneous rocks that form above the earth's surface. They cool quickly and form small crystals. Example are basalt (made from lava) and pumicestone (formed when lava is forcefully ejected from a volcano and air bubbles form within the rock). ...
Foundations of Social Studies GEOGRAPHY
Foundations of Social Studies GEOGRAPHY

... External Processes The surface of the earth is subject to forces which change its shape. The most important forces are weathering and erosion. Weathering occurs when rock surfaces decompose and begin to break up. Erosion refers to the actual movement of the broken particles away from their source. T ...
Plate Tectonic Theory
Plate Tectonic Theory

... Wegener was also intrigued by the occurrences of unusual geologic structures and of plant and animal fossils found on the matching coastlines of South America and Africa, which are now widely separated by the Atlantic Ocean.  He reasoned that it was physically impossible for most of these organisms ...
Plate Tectonics
Plate Tectonics

... which drifted apart and are still moving. 3 pieces of evidence to support this theory – 1.continent boundaries fit together like a puzzle – 2.fossils of same organisms found on different continents • a. Mesosuras- reptile • b. Glosopteris- fern plant – 3.Glaciar evidence in different climates *Wegne ...
Structure of the earth
Structure of the earth

... Crust • the outer layer of the earth is composed of soil and solid rock • Continental crust- composed primarily of granite, is thicker sedimentary and metamorphic rocks which form the continents • Oceanic crust- composed primarily of basalt, is thinner. ...
GG 101 Fall 2010 Exam 1 September 23, 2010
GG 101 Fall 2010 Exam 1 September 23, 2010

... B) In a tropical rainforest, the forest-floor litter is often burned during the dry season. C) Less humus is produced in the cool, temperate forest but the rate of decay and oxidation is slower than in a tropical rainforest. D) No humus is produced in a tropical rainforest because the B horizon is p ...
PPT-chp-6_edited
PPT-chp-6_edited

... destroyed over the last 4.6 billion years Altered due to physical, chemical, and biological processes ...
Earth Egg Model
Earth Egg Model

... Earth Egg Model – Teacher Notes There is a common student misconception that the core and mantle of our Earth are liquid and only the crust is solid. This might have been true at the very beginning of planetary formation about 4.54 billion years ago but not so now. Earth egg model Student activitie ...
Chapter 2: The Earth
Chapter 2: The Earth

... o At the center of the planet is a super hot, solid inner core. 4,000 miles below the Earth’s surface. o Surrounding the inner core is a liquid outer core. This is a liquid band of nickel & iron. This section begins at 1,800 miles below Earth’s surface. o The layer that contains thick, dense rock is ...
oceanic ridges
oceanic ridges

... Collison zones form where both sides of a convergent boundary consist of continental (buoyant) material. Modern example: Himalayas ...
crust
crust

... The Four Layers The Earth is composed of four different layers. The crust is the layer that you live on, and it is the most widely studied and understood. The mantle is much hotter and has the ability to flow. The outer core and inner core are even hotter with pressures so great you would be squeez ...
Rock Cycle 200 - FitzBrownBodleTeam
Rock Cycle 200 - FitzBrownBodleTeam

... Oceanic crust is made of basalt and Continental crust is made out of granite. ...
Geology Content from the Frameworks
Geology Content from the Frameworks

...  Igneous rock undergoes weathering (or breakdown) to form sediment. The sediment is transported and deposited somewhere (such as at the beach or in a delta, or in the deep sea).  Igneous rocks are classified (or named) based on their composition (which minerals they contain) and texture (or the si ...
Geology Paper III
Geology Paper III

... and magnesium, c) silicon and aluminum, d) magnesiumand aluminum, e) magnesiumand silicon. ...
Our_Dynamic_Earth_2012
Our_Dynamic_Earth_2012

... Convection currents within the mantle ...
Molnar, P. (2011), Jack Oliver (1923-2011), Nature, 470, 176.
Molnar, P. (2011), Jack Oliver (1923-2011), Nature, 470, 176.

... with unusually high frequencies. They realized that the lithosphere (which includes the planet’s crust and the uppermost ‘cool’ part of the mantle) underlying the Pacific Ocean to the east had plunged to a depth of 700 kilometres. Much of the scientific community was slow to appreciate their insight ...
14 - Plasticity
14 - Plasticity

... Since no one has reached the mantle, scientists can only guess as to its actual make-up. All earthquake waves can pass through the mantle, which means it is a solid (S-waves cannot pass through liquids). Yet the tectonic plates of the earth “float” on the mantle, moving by convection currents in the ...
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Age of the Earth



The age of the Earth is 4.54 ± 0.05 billion years (4.54 × 109 years ± 1%). This age is based on evidence from radiometric age dating of meteorite material and is consistent with the radiometric ages of the oldest-known terrestrial and lunar samples.Following the development of radiometric age dating in the early 20th century, measurements of lead in uranium-rich minerals showed that some were in excess of a billion years old.The oldest such minerals analyzed to date—small crystals of zircon from the Jack Hills of Western Australia—are at least 4.404 billion years old. Comparing the mass and luminosity of the Sun to those of other stars, it appears that the Solar System cannot be much older than those rocks. Calcium-aluminium-rich inclusions – the oldest known solid constituents within meteorites that are formed within the Solar System – are 4.567 billion years old, giving an age for the solar system and an upper limit for the age of Earth.It is hypothesised that the accretion of Earth began soon after the formation of the calcium-aluminium-rich inclusions and the meteorites. Because the exact amount of time this accretion process took is not yet known, and the predictions from different accretion models range from a few millions up to about 100 million years, the exact age of Earth is difficult to determine. It is also difficult to determine the exact age of the oldest rocks on Earth, exposed at the surface, as they are aggregates of minerals of possibly different ages.
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