Some information on geology - Revision history

wikademia>Wikademia at 06:17, 13 June 2009

2009-06-13T06:17:12Z

← Older revision		Revision as of 06:17, 13 June 2009
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	Geology can be split into two main branches: historical and physical. Historical geology attempts to understand the origins, composition, systems and changes of the Earth.		Geology can be split into two main branches: historical and physical. Historical geology attempts to understand the origins, composition, systems and changes of the Earth.
			{{?}}
	=History=		=History=
	According to the widely accepted [[w:Big Bang\|Big Bang]] theory, the [[w:Universe\|Universe]] began at some point in space and time around 13,700,000,000 years ago, as evidenced by the [[w:doppler effect\|doppler effect]] observed in all stars and a 3 degree Kelvin background radiation observed elsewhere.		According to the widely accepted [[w:Big Bang\|Big Bang]] theory, the [[w:Universe\|Universe]] began at some point in space and time around 13,700,000,000 years ago, as evidenced by the [[w:doppler effect\|doppler effect]] observed in all stars and a 3 degree Kelvin background radiation observed elsewhere.

wikademia>Wikademia: 21 revisions

2009-05-11T21:00:48Z

21 revisions

← Older revision	Revision as of 21:00, 11 May 2009
(No difference)

68.5.6.229: /* Structure and Composition of the Earth */

2008-12-25T02:36:06Z

Structure and Composition of the Earth

← Older revision		Revision as of 02:36, 25 December 2008
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	The mantle stretches from the base of the crust to approximately 2900km, and is divided into three zones: the upper mantle, the transition zone and the lower mantle. The upper mantle is rich in dunite, peridotite and eclogite rocks, and is heterogeneous (probably due to partial melting of mantle magmas). Magma is continuous extracted from the upper mantle. The transition zone, between the upper and lower mantle, is marked by polymorphic phase transition from spinel and pyroxene to ilmenite and rutile, then eventually to stishovite. In the transition zone, due to higher pressure at a greater depth, rocks have more closely packed structures than those in the upper mantle and crust. The lower mantle appears to be homogeneous, with even denser, very closely packed materials.		The mantle stretches from the base of the crust to approximately 2900km, and is divided into three zones: the upper mantle, the transition zone and the lower mantle. The upper mantle is rich in dunite, peridotite and eclogite rocks, and is heterogeneous (probably due to partial melting of mantle magmas). Magma is continuous extracted from the upper mantle. The transition zone, between the upper and lower mantle, is marked by polymorphic phase transition from spinel and pyroxene to ilmenite and rutile, then eventually to stishovite. In the transition zone, due to higher pressure at a greater depth, rocks have more closely packed structures than those in the upper mantle and crust. The lower mantle appears to be homogeneous, with even denser, very closely packed materials.

	Physical properties of the earth's core suggest that it is made up mainly of iron and nickel allows. The outer core is ~~solid~~, while the inner core is ~~liquid~~. Physical properties of the core suggest that it is made up mainly of iron and nickel alloys.		Physical properties of the earth's core suggest that it is made up mainly of iron and nickel allows. The outer core is liquid, while the inner core is solid. Physical properties of the core suggest that it is made up mainly of iron and nickel alloys.

	=Plate Tectonics=		=Plate Tectonics=

wikademia>Riffsyphon1024 at 04:01, 14 January 2008

2008-01-14T04:01:11Z

← Older revision		Revision as of 04:01, 14 January 2008
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	Geology (from Greek γη- (ge-, "the earth") and λογος ("logos", "word", "reason")) is the science and study of the solid matter of a celestial body, its composition, structure, physical properties, history and the processes that shape it. In this book, the term Geology will apply to the Earth in particular.		'''Geology''' (from Greek γη- (ge-, "the earth") and λογος ("logos", "word", "reason")) is the science and study of the solid matter of a celestial body, its composition, structure, physical properties, history and the processes that shape it. In this book, the term Geology will apply to the [[w:Earth\|Earth]] in particular.

	Geology can be split into two main branches: historical and physical. Historical geology attempts to understand the origins, composition, systems and changes of the Earth.		Geology can be split into two main branches: historical and physical. Historical geology attempts to understand the origins, composition, systems and changes of the Earth.

	~~<h1>~~History~~</h1>~~		=History=
	According to the widely accepted Big Bang theory, the Universe began at some point in space and time around 13,700,000,000 years ago, as evidenced by the doppler effect observed in all stars and a 3 degree Kelvin background radiation observed elsewhere.		According to the widely accepted [[w:Big Bang\|Big Bang]] theory, the [[w:Universe\|Universe]] began at some point in space and time around 13,700,000,000 years ago, as evidenced by the [[w:doppler effect\|doppler effect]] observed in all stars and a 3 degree Kelvin background radiation observed elsewhere.

	In about 10E-43 seconds, physics became defined and gravity separated from other forces. The Universe was 10E32 K in temperature.		*In about 10E-43 seconds, physics became defined and gravity separated from other forces. The Universe was 10E32 K in temperature.
			*At 10E-35 seconds, the Universe expanded to the size of a softball and the [[w:strong nuclear force\|strong nuclear force]] separated. Energy turned into [[w:quark\|quark]]s and electrons and their anti-matter counterparts. The temperature was 1027 K.
	At 10E-35 seconds, the Universe expanded to the size of a softball and the strong nuclear force separated. Energy turned into ~~quarks~~ and electrons and their anti-matter counterparts. The temperature was 1027 K.		*At 10E-6 seconds, quarks began to bind into protons and neutrons; matter and antimatter destroyed each other and the balance turned out to be in favor of matter. The Universe was about the size of our solar system and 1013 K hot.
			*1 second after its inception, the electromagnetic and weak nuclear forces appeared as the Universe cooled to 109 K.
	At 10E-6 seconds quarks began to bind into protons and neutrons; matter and antimatter destroyed each other and the balance turned out to be in favor of matter. The Universe was about the size of our solar system and 1013 K hot.		*3 minutes later, protons and neutrons fused into nuclei.
			*After 100,000 years, the electrons and the nuclei came together to form atoms; photons separated from matter and there was light.
	1 second after its inception, the electromagnetic and weak nuclear forces appeared as the Universe cooled to 109 K.		*In the next 1,000,000,000 years the Universe became clumpy as galaxies began to take shape.
			*Ever since then, the Universe has cooled down to 3 K, galaxies have developed, generations of stars have passed, creating heavier elements, and life has appeared. Our galaxy, the Milky Way, contains about 200,000,000,000 stars and lies 1 million light years from its nearest neighbor.
	3 minutes later, protons and neutrons fused into nuclei.		*The solar system was formed around 4,600,000,000 years ago as dust collapsed into the protostar that was to become the Sun, and into planetesimals orbiting it. The inner planets, from Mercury to Mars, are solid because the solar winds have driven gases away and have a core; the outer planets are larger and consist of gas.

	After 100,000 years, the electrons and the nuclei came together to form atoms; photons separated from matter and there was light.

	In the next 1,000,000,000 years the Universe became clumpy as galaxies began to take shape.

	Ever since then, the Universe has cooled down to 3 K, galaxies have developed, generations of stars have passed, creating heavier elements, and life has appeared.

	Our galaxy, the Milky Way, contains about 200,000,000,000 stars and lies 1 million light years from its nearest neighbor.

	The solar system was formed around 4,600,000,000 years ago as dust collapsed into the protostar that was to become the Sun, and into planetesimals orbiting it.

	The inner planets, from Mercury to Mars, are solid because the solar winds have driven gases away and have a core; the outer planets are larger and consist of gas.

	~~<h1>Structure and Composition of the Earth<h1>~~
	The outmost layer of the earth is called the lithosphere (100-200km deep); it is followed by a plastic asthenosphere (150-400km deep). Independent of these classifications, the internal structure of the earth is divided into three main layers: the crust, the mantle and the core.

			=Structure and Composition of the Earth=
			The outermost layer of the earth is called the lithosphere (100-200km deep); it is followed by a plastic asthenosphere (150-400km deep). Independent of these classifications, the internal structure of the earth is divided into three main layers: the crust, the mantle and the core.

	The crust, which is solid and mainly made up of silicates, can be divided into continental crust and oceanic crust. The continental crust ranges in thickness from 35-60km. It is andesitic in composition, with a Si0<sub>2</sub> composition of 57% by weight. 95% of crustal rocks are igneous and metamorphic, while only 5% are sedimentary. These range from granite near the surface to gabbro, deep down near the mantle. The oceanic crust is much thinner than the continental crust, with an average thickness of just 5km. It is denser than the continental crust and mainly composed of basaltic rocks, giving it a SiO<sub>2</sub> content of 49% by weight. The atmosphere, hydrosphere and biosphere are often also considered to be part of the crust.		The crust, which is solid and mainly made up of silicates, can be divided into continental crust and oceanic crust. The continental crust ranges in thickness from 35-60km. It is andesitic in composition, with a Si0<sub>2</sub> composition of 57% by weight. 95% of crustal rocks are igneous and metamorphic, while only 5% are sedimentary. These range from granite near the surface to gabbro, deep down near the mantle. The oceanic crust is much thinner than the continental crust, with an average thickness of just 5km. It is denser than the continental crust and mainly composed of basaltic rocks, giving it a SiO<sub>2</sub> content of 49% by weight. The atmosphere, hydrosphere and biosphere are often also considered to be part of the crust.

			The mantle stretches from the base of the crust to approximately 2900km, and is divided into three zones: the upper mantle, the transition zone and the lower mantle. The upper mantle is rich in dunite, peridotite and eclogite rocks, and is heterogeneous (probably due to partial melting of mantle magmas). Magma is continuous extracted from the upper mantle. The transition zone, between the upper and lower mantle, is marked by polymorphic phase transition from spinel and pyroxene to ilmenite and rutile, then eventually to stishovite. In the transition zone, due to higher pressure at a greater depth, rocks have more closely packed structures than those in the upper mantle and crust. The lower mantle appears to be homogeneous, with even denser, very closely packed materials.

	The mantle stretches from the bas of the crust to approximately 2900km, and is divided into three zones: the upper mantle, the transition zone and the lower mantle. The upper mantle is rich in dunite, peridotite and eclogite rocks, and is heterogenoud (probably due to partial melting of mantle magmas). Magma is continuous extracted from the upper mantle. The transition zone, between the upper and lower mantle, is marked by polymorphic phase transition from spinel and pyroxene to ilmenite and rutile, then eventually to stishovite. In the transition zone, due to higher pressure at a greater depth, rocks have more closely packed structures than those in the upper mantle and crust. The lower mantle appears to be homogenous, with even denser, very closely packed materials.		Physical properties of the earth's core suggest that it is made up mainly of iron and nickel allows. The outer core is solid, while the inner core is liquid. Physical properties of the core suggest that it is made up mainly of iron and nickel alloys.


	Physical properties of the earth's core suggest that it is made up mainly of iron and nickel allows. The outer core is solid, while the inner core is liquid.

	Physical properties of the core suggest that it is made up mainly of iron and nickel alloys.

	~~<h1>~~Plate Tectonics~~</h1>~~		=Plate Tectonics=
	Because of the interactions between the lithosphere, the asthenosphere, and the mantle underneath, our planet's crust is governed by 'plate tectonics.'		Because of the interactions between the lithosphere, the asthenosphere, and the mantle underneath, our planet's crust is governed by 'plate tectonics.'

	Plate tectonics is a theory based on the principle of Uniformitarianism, which reads: "The Present is the Key to the Past." The earth in its current state is the result of natural processes operating over vast periods of time, and can be understood by watching the action of ongoing processes.		Plate tectonics is a theory based on the principle of Uniformitarianism, which reads: "The Present is the Key to the Past." The earth in its current state is the result of natural processes operating over vast periods of time, and can be understood by watching the action of ongoing processes.

			=Volcanism=

	~~<h1>~~Volcanism~~</h1>~~
	There are three(3) types of lavas formed by volcanoes. Mafic, Intermediate, and Felsic.<br>		There are three(3) types of lavas formed by volcanoes. Mafic, Intermediate, and Felsic.<br>
	<~~B><U~~>Mafic~~</B><U>~~(Basaltic)</U><br>		<u>'''Mafic'''(Basaltic)</u><br>
	~~<li>~~%SiO2: < 50%</li>		*%SiO2: < 50%</li>
	~~<li>~~%FeMg: 4%</li>		*%FeMg: 4%</li>
	~~<li>~~Temp: up to 1500C</li>		*Temp: up to 1500C</li>
	~~<li>~~Viscosity: Low</li>		*Viscosity: Low</li>
	~~<li>~~Eruptive Behavior: gentle</li>		*Eruptive Behavior: gentle</li>
	~~<li>~~Distribution: divergent plate boundries, hot spots, convergent plate boundries</li>		*Distribution: divergent plate boundries, hot spots, convergent plate boundries</li>

	~~<B>~~<U>Intermediate~~</B><U>~~(Andesitic)</U><br>		<U>'''Intermediate'''(Andesitic)</U><br>
	~~<li>~~%SiO2: ~60%</li>		*%SiO2: ~60%</li>
	~~<li>~~%FeMg: ~3%</li>		*%FeMg: ~3%</li>
	~~<li>~~Temp: ~1000C</li>		*Temp: ~1000C</li>
	~~<li>~~Viscosity: Intermediate</li>		*Viscosity: Intermediate</li>
	~~<li>~~Eruptive Behavior: explosive</li>		*Eruptive Behavior: explosive</li>
	~~<li>~~Distribution: convergent plate boundries</li>		*Distribution: convergent plate boundries</li>

	~~<B>~~<U>Felsic~~</B><U>~~(Rhyolitic)</U><br>		<U>'''Felsic''' (Rhyolitic)</U><br>
	~~<li>~~%SiO2: >70%</li>		*%SiO2: >70%</li>
	~~<li>~~%FeMg: 2%</li>		*%FeMg: 2%</li>
	~~<li>~~Temp: 700C</li>		*Temp: 700C</li>
	~~<li>~~Viscosity: High</li>		*Viscosity: High</li>
	~~<li>~~Eruptive Behavior: explosive</li>		*Eruptive Behavior: explosive</li>
	~~<li>~~Distribution: hot spots in continental crusts (Yellowstone National Park), convergent plate boundries </li>		*Distribution: hot spots in continental crusts (Yellowstone National Park), convergent plate boundries </li>

	[[Category:Geology]]		[[Category:Geology]]

143.97.2.35 at 14:06, 13 January 2008

2008-01-13T14:06:20Z

← Older revision		Revision as of 14:06, 13 January 2008
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	<h1>History</h1>		<h1>History</h1>
	According to the widely accepted Big Bang theory, the Universe began at some point in space and time around 15,~~500~~,000,000 years ago, as evidenced by the doppler effect observed in all stars and a 3 degree Kelvin background radiation observed elsewhere.		According to the widely accepted Big Bang theory, the Universe began at some point in space and time around 13,700,000,000 years ago, as evidenced by the doppler effect observed in all stars and a 3 degree Kelvin background radiation observed elsewhere.

	In about 10E-43 seconds, physics became defined and gravity separated from other forces. The Universe was 10E32 K in temperature.		In about 10E-43 seconds, physics became defined and gravity separated from other forces. The Universe was 10E32 K in temperature.

wikademia>Nisha13: added information about mantle and core

2007-11-17T11:03:34Z

added information about mantle and core

← Older revision		Revision as of 11:03, 17 November 2007
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	<h1>Structure and Composition of the Earth<h1>		<h1>Structure and Composition of the Earth<h1>
	~~The Earth has a solid crust made of silicates, a mantle also made of silicates, and a core made of iron.~~ The outmost layer is called the lithosphere (100-200km deep); it is followed by a plastic asthenosphere (150-400km deep). ~~The~~ crust ~~lies above a solid mesosphere that goes down to 2900km. The core has a liquid outer core~~ and ~~solid inner~~ core.		The outmost layer of the earth is called the lithosphere (100-200km deep); it is followed by a plastic asthenosphere (150-400km deep). Independent of these classifications, the internal structure of the earth is divided into three main layers: the crust, the mantle and the core.

	~~The internal structure of the earth consists of three main layers: the crust, the mantle and the core.~~

	The crust, which is solid and mainly made up of silicates, can be divided into continental crust and oceanic crust. The continental crust ranges in thickness from 35-60km. It is andesitic in composition, with a Si0<sub>2</sub> composition of 57% by weight. 95% of crustal rocks are igneous and metamorphic, while only 5% are sedimentary. These range from granite near the surface to gabbro, deep down near the mantle. The oceanic crust is much thinner than the continental crust, with an average thickness of just 5km. It is denser than the continental crust and mainly composed of basaltic rocks, giving it a SiO<sub>2</sub> content of 49% by weight. The atmosphere, hydrosphere and biosphere are often also considered to be part of the crust.		The crust, which is solid and mainly made up of silicates, can be divided into continental crust and oceanic crust. The continental crust ranges in thickness from 35-60km. It is andesitic in composition, with a Si0<sub>2</sub> composition of 57% by weight. 95% of crustal rocks are igneous and metamorphic, while only 5% are sedimentary. These range from granite near the surface to gabbro, deep down near the mantle. The oceanic crust is much thinner than the continental crust, with an average thickness of just 5km. It is denser than the continental crust and mainly composed of basaltic rocks, giving it a SiO<sub>2</sub> content of 49% by weight. The atmosphere, hydrosphere and biosphere are often also considered to be part of the crust.


			The mantle stretches from the bas of the crust to approximately 2900km, and is divided into three zones: the upper mantle, the transition zone and the lower mantle. The upper mantle is rich in dunite, peridotite and eclogite rocks, and is heterogenoud (probably due to partial melting of mantle magmas). Magma is continuous extracted from the upper mantle. The transition zone, between the upper and lower mantle, is marked by polymorphic phase transition from spinel and pyroxene to ilmenite and rutile, then eventually to stishovite. In the transition zone, due to higher pressure at a greater depth, rocks have more closely packed structures than those in the upper mantle and crust. The lower mantle appears to be homogenous, with even denser, very closely packed materials.


			Physical properties of the earth's core suggest that it is made up mainly of iron and nickel allows. The outer core is solid, while the inner core is liquid.

	Physical properties of the core suggest that it is made up mainly of iron and nickel alloys.		Physical properties of the core suggest that it is made up mainly of iron and nickel alloys.

wikademia>Nisha13: added information about crust. will post on mantle and core shortly

2007-11-17T08:04:05Z

added information about crust. will post on mantle and core shortly

← Older revision		Revision as of 08:04, 17 November 2007
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	The inner planets, from Mercury to Mars, are solid because the solar winds have driven gases away and have a core; the outer planets are larger and consist of gas.		The inner planets, from Mercury to Mars, are solid because the solar winds have driven gases away and have a core; the outer planets are larger and consist of gas.

	The Earth has a solid crust made of silicates, a mantle also made of silicates, and a core made of iron. The outmost layer is called the lithosphere (100-200km deep); it is followed by a plastic asthenosphere (150-400km deep). The crust lies above a solid mesosphere that goes down to 2900km. The core has an ~~outer~~		<h1>Structure and Composition of the Earth<h1>
			The Earth has a solid crust made of silicates, a mantle also made of silicates, and a core made of iron. The outmost layer is called the lithosphere (100-200km deep); it is followed by a plastic asthenosphere (150-400km deep). The crust lies above a solid mesosphere that goes down to 2900km. The core has a liquid outer core and solid inner core.

			The internal structure of the earth consists of three main layers: the crust, the mantle and the core.

			The crust, which is solid and mainly made up of silicates, can be divided into continental crust and oceanic crust. The continental crust ranges in thickness from 35-60km. It is andesitic in composition, with a Si0<sub>2</sub> composition of 57% by weight. 95% of crustal rocks are igneous and metamorphic, while only 5% are sedimentary. These range from granite near the surface to gabbro, deep down near the mantle. The oceanic crust is much thinner than the continental crust, with an average thickness of just 5km. It is denser than the continental crust and mainly composed of basaltic rocks, giving it a SiO<sub>2</sub> content of 49% by weight. The atmosphere, hydrosphere and biosphere are often also considered to be part of the crust.


			Physical properties of the core suggest that it is made up mainly of iron and nickel alloys.

	<h1>Plate Tectonics</h1>		<h1>Plate Tectonics</h1>

wikademia>Robert Horning: Refining catalog classification

2007-07-01T21:57:04Z

Refining catalog classification

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	{{alphabetical\|G}}		{{alphabetical\|G}}
	{{shelf\|Natural sciences}}		{{shelf\|Natural sciences}}
	{{DDC\|500}}		{{DDC\|500\|551}}
	{{LOC\|Q}}		{{LOC\|QE\|QE1}}

wikademia>Wknight8111: Processing page text

2007-06-25T22:08:48Z

Processing page text

← Older revision		Revision as of 22:08, 25 June 2007
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	[[Category:Geology]]		[[Category:Geology]]
			{{alphabetical\|G}}
			{{shelf\|Natural sciences}}
			{{DDC\|500}}
			{{LOC\|Q}}

82.198.250.80: sp

2007-02-09T11:24:44Z

← Older revision		Revision as of 11:24, 9 February 2007
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	Geology (from Greek γη- (ge-, "the earth") and λογος (logos, "word", "reason")) is the science and study of the solid matter of a celestial body, its composition, structure, physical properties, history and the processes that shape it. In this book, the term Geology will apply to the Earth in particular.		Geology (from Greek γη- (ge-, "the earth") and λογος ("logos", "word", "reason")) is the science and study of the solid matter of a celestial body, its composition, structure, physical properties, history and the processes that shape it. In this book, the term Geology will apply to the Earth in particular.

	Geology can be split into two main branches: historical and physical. Historical geology attempts to understand the origins, composition, systems and changes of the Earth.		Geology can be split into two main branches: historical and physical. Historical geology attempts to understand the origins, composition, systems and changes of the Earth.

← Older revision		Revision as of 21:57, 1 July 2007
Line 66:		Line 66:
	{{alphabetical\|G}}		{{alphabetical\|G}}
	{{shelf\|Natural sciences}}		{{shelf\|Natural sciences}}
	{{DDC\|500}}		{{DDC\|500\|551}}
	{{LOC\|Q}}		{{LOC\|QE\|QE1}}