Minerals are basic constituents of rocks, which builds lithosphere of the Earth,
and other planets, their satellites, asteroids and meteor.
Performance of minerals:
-homogeneous structure,
-defined chemical composition,
-certain structures of properly distributed in space (crystalline) or without an order (without amorphous-crystalline structure).
Only minerals with a crystal lattice are called crystals.
Minerals consist of atoms, ions, ionic groups and molecules that may be connected in various ways (ionic bond, covalent bond, electrostatic forces, van der Waals forces).
Mineral grains vary in size (visible eye, microscope, electron microscope-macro, micro.
The performances of crystallized minerals depend on the ingredients and location
grid, which is a reflection of their geometrically correct spatial
schedule. There are 6 crystall system.
Performance of minerals:
-Cleavage, hardness, density, color, luster,
-Velocity of light, heat and electricity,
-Angles of refraction and reflection,
-Radioactivity, magnetic properties, etc.
Polymorphism-chemical combination of the same chemical composition of different forms of crystal lattice (eg graphite and diamond-C or calcite and aragonite).
Classification of minerals according to chemical composition
Silicate minerals
Their spatial structure of form, face, or chain connected SiO4 tetrahedra which are located between the metal atoms (silicon atom in the middle, and the tops are tetrahedron of oxygen atoms).
1) Spatial linked tetrahedra with all four of the top (60% of the lithosphere)
feldspar (Orthoclase and sanidine), plagioclase (albite-anortite)
2) Flat View linked tetrahedra in single and dual low
associated layer-characterized by strong cleavage.
micas (muscovite, biotite), chlorite, talc, clay minerals (kaolinite, illite, montmorillonite)
3) Single chain linked tetrahedra
(Pyroxenes)
4) Double chains of tetrahedra
(Tremolite, actinolite, hornblende, glaucophane)
5) silicate minerals with independent tetrahedra
Monday, September 13, 2010
Tuesday, September 7, 2010
Earth crust layers
Crust
-Average depth beneath the continents is about 40 km,and 10-12 km beneath the ocean,
-Chemical composition of the most complex as a result of geochemical differentiation during formation of the Earth and the physical and chemical changes which subsequently occurred.
Continental crust-acidic aluminosilicate rocks (granite)
-SIAL (Si + Al),
-Miss at the bottom of the ocean.
Oceanic crust-mafic rocks (basalt) + covering sediment deposits average thickness in the oceans ≈ 450 m,
SIMA-(Si + Mg)
In basaltic crust are sometimes printed and rocks from the upper mantle.
Lithosphere (crust + upper mantle)
The lithosphere is the common exposed structural(Tectonic changes).Structural changes usually are caused by the dynamics of asthenosphere.
The two surfaces of discontinuity(Wiechert-Guttenberg(Core / sheath) and Moho (crust / mantle).
Isostasy
Isostasy is a balance between the dipped pieces (blocks) broken off the Earth crust that floats on the plastic and denser upper mantle (like a piece of wood or icebergs that float on water).Simplified, eg by Buoyancy, body immersed in water because of its weight oust the amount of water equal to their volume.Simply put, we can imagine the broken off pieces of bark to dive into the upper mantle and in accordance with its weight of push mantle, where each piece is in equilibrium with the adjacent piece because each piece has the same mass.
If we imagine that parts of the crust and upper mantle form separate vertical columns, then it is at the bottom of their bases the same pressure.
GRAVITY
The force of gravity between two objects varies depending on the mass of objects and their mutual distances according to the relation:
mA* mB
G = k --------------
l * l
The force of gravity increases with the mass of observed objects and the reduction of their
distance (between the celestial bodies, stars and planets and their satellites is much higher than between two objects on the Earth).
-Average depth beneath the continents is about 40 km,and 10-12 km beneath the ocean,
-Chemical composition of the most complex as a result of geochemical differentiation during formation of the Earth and the physical and chemical changes which subsequently occurred.
Continental crust-acidic aluminosilicate rocks (granite)
-SIAL (Si + Al),
-Miss at the bottom of the ocean.
Oceanic crust-mafic rocks (basalt) + covering sediment deposits average thickness in the oceans ≈ 450 m,
SIMA-(Si + Mg)
In basaltic crust are sometimes printed and rocks from the upper mantle.
Lithosphere (crust + upper mantle)
The lithosphere is the common exposed structural(Tectonic changes).Structural changes usually are caused by the dynamics of asthenosphere.
The two surfaces of discontinuity(Wiechert-Guttenberg(Core / sheath) and Moho (crust / mantle).
Isostasy
Isostasy is a balance between the dipped pieces (blocks) broken off the Earth crust that floats on the plastic and denser upper mantle (like a piece of wood or icebergs that float on water).Simplified, eg by Buoyancy, body immersed in water because of its weight oust the amount of water equal to their volume.Simply put, we can imagine the broken off pieces of bark to dive into the upper mantle and in accordance with its weight of push mantle, where each piece is in equilibrium with the adjacent piece because each piece has the same mass.
If we imagine that parts of the crust and upper mantle form separate vertical columns, then it is at the bottom of their bases the same pressure.
GRAVITY
The force of gravity between two objects varies depending on the mass of objects and their mutual distances according to the relation:
mA* mB
G = k --------------
l * l
The force of gravity increases with the mass of observed objects and the reduction of their
distance (between the celestial bodies, stars and planets and their satellites is much higher than between two objects on the Earth).
General structure of the Earth
The shape of the geoid
Due to rotation of the masses at the poles the Earth is flattened, and its size in the continental rises above the shape of a rotational ellipsoid, and in the oceans under the form of a rotational ellipsoid.
(er=6377 km, rp= 6356km)
Density increases from the surface toward the center (2.7 to 11 g/cm3),
The temperature rises from the surface towards the central part (4000 -5000 ° C)
Early Earth was probably a uniform heterogeneous chemical composition and density.
The temperature of the early Earth during the aggregation process has reached the melting point of the elements iron and nickel, which were thicker and heavier than the spec of other ingredients and concentrated in the center of the Earth. At the same time, the lighter elements that form the silicate minerals are pulled toward the surface, forming the mantle and crust.Geochemical differentiation was made lupin, layered or zonal structure of the Earth which, in the middle of dense Fe-Ni core, the iron-rich silicate mantle and the silicate Earth's crust.
Crust (barysphere)
-depth> 5080 -2900 km, the mean density of ≈ 10.7 g/cm3, T = 4000 -5000 C,
-inner core-solid core of iron and nickel
-Depth> 5080 km,
-outer-core liquid alloy of iron and nickel, probably contains some light elements like oxygen and sulfur
-Depth: 2900 -5080 km,
-Liquid-metal mass convection motion → important for restoring geomagnetism.
Mantle
1) the lower mantle or the Mesosphere
-Depth to ≈ 2900 -1000 km
-Oxides and silicates, probably a little iron
-Heterogeneous environment, revealed differences in the moving speed of the waves and the density molten material.
2) Middle mantle or asthenosphere
-Depth of ≈ 1000-400 km
-Heterogeneous environment, revealed differences in the moving speed of the waves and the density matter,
-Established thermal dynamics of the convection layer with accompanying movement of molten material.
3) The upper mantle
-To a depth of ≈ 400 km,
Rocky and built from the ultramafic rocks (peridotite beneath the continents, Eclogite, below the oceanic crust and lercolit harcburgit)
Due to rotation of the masses at the poles the Earth is flattened, and its size in the continental rises above the shape of a rotational ellipsoid, and in the oceans under the form of a rotational ellipsoid.
(er=6377 km, rp= 6356km)
Density increases from the surface toward the center (2.7 to 11 g/cm3),
The temperature rises from the surface towards the central part (4000 -5000 ° C)
Early Earth was probably a uniform heterogeneous chemical composition and density.
The temperature of the early Earth during the aggregation process has reached the melting point of the elements iron and nickel, which were thicker and heavier than the spec of other ingredients and concentrated in the center of the Earth. At the same time, the lighter elements that form the silicate minerals are pulled toward the surface, forming the mantle and crust.Geochemical differentiation was made lupin, layered or zonal structure of the Earth which, in the middle of dense Fe-Ni core, the iron-rich silicate mantle and the silicate Earth's crust.
Crust (barysphere)
-depth> 5080 -2900 km, the mean density of ≈ 10.7 g/cm3, T = 4000 -5000 C,
-inner core-solid core of iron and nickel
-Depth> 5080 km,
-outer-core liquid alloy of iron and nickel, probably contains some light elements like oxygen and sulfur
-Depth: 2900 -5080 km,
-Liquid-metal mass convection motion → important for restoring geomagnetism.
Mantle
1) the lower mantle or the Mesosphere
-Depth to ≈ 2900 -1000 km
-Oxides and silicates, probably a little iron
-Heterogeneous environment, revealed differences in the moving speed of the waves and the density molten material.
2) Middle mantle or asthenosphere
-Depth of ≈ 1000-400 km
-Heterogeneous environment, revealed differences in the moving speed of the waves and the density matter,
-Established thermal dynamics of the convection layer with accompanying movement of molten material.
3) The upper mantle
-To a depth of ≈ 400 km,
Rocky and built from the ultramafic rocks (peridotite beneath the continents, Eclogite, below the oceanic crust and lercolit harcburgit)
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