ROCK TYPESOCEAN FLOORS: BASALT BASEMENT; & CONTINENTS: GRANITE BASEMENT
- The Seafloors are mostly Basalt, about 3 miles thick, which cooled and solidified slowly, so the grains are microscopic. The Continents are mostly Granite, which is identical to Basalt, except the grains are larger, indicating that Granite cooled and solidified quickly. Gentry's radio-halo Inclusions in Granite, with parentless Po, also indicate quick solidification of the Granite Continents. It seems likely that Granite should initially have covered the entire Earth, because the outer layer would have been exposed to colder temperature, where solidification/crystallization would occur rapidly.
IGNEOUS, METAMORPHIC & SEDIMENTARY ROCK
- Basalt & Granite are mostly Igneous rock. Some granite is metamorphic. Metamorphic shale, sandstone and limestone are Slate, Quartzite & Marble respectively.
- Sedimentary Rock is layered Rock that covers 75% of Earth's continental surface from 2 to 6 miles deep. Sedimentary Rock was laid down by
electrical deposition the Great Flood. 10-15% of Sedimentary Rock is Limestone. Limestone under the Bahamas is 3 miles deep. Limestone consists of Calcium etc, apparently from Seawater. Shale is common, 50-70% of all Sedimentary Rock, made from Clay Soil. Sandstone is the third type, about 20% of rock, and it is made from Sand, which is mostly silicon dioxide, SiO2.
Most Common Mineral of the Continents is Silica, SiO2, mostly Quartz (26% of Continents)
Most Common Mineral of the Crust (Continents & Ocean Floors combined) is Feldspar, Ca,K,NaAl2Si2O8 (60% of Crust)
Most Common Mineral of Earth (Crust and Mantle combined) is Bridgmanite, Mg/FeSiO3 (38% of Earth)
MINERAL COMPOSITIONMineral Densities
www.engineeringtoolbox.com/mineral-density-d_1555.htmlMineral Classification
www.rocksandminerals4u.com/mineral_classification.html_Native Elements: This is the category of the pure. Most minerals are made up of combinations of chemical elements. In this group a single element like the copper shown here are found in a naturally pure form.
_Silicates is the largest group of minerals. Silicates are made from metals combined with silicon and oxygen. There are more silicates than all other minerals put together.The mica on the left is a member of this group.
_Oxides form from the combination of a metal with oxygen. This group ranges from dull ores like bauxite to gems like rubies and sapphires. The magnetite pictured to the left is a member of this group.
_Sulfides are made of compounds of sulfur usually with a metal. They tend to be heavy and brittle. Several important metal ores come from this group like the pyrite pictured here that is an iron ore.
_Slufates are made of compounds of sulfur combined with metals and oxygen. It is a large group of minerals that tend to be soft, and translucent like this barite.
_Halides form from halogen elements like chlorine, bromine, fluorine, and iodine combined with metallic elements. They are very soft and easily dissolved in water. Halite is a well known example of this group. Its chemical formula is NaCl or sodium chloride commonly known as table salt.
_Carbonates are a group of minerals made of carbon, oxygen, and a metallic element. This calcite known as calcium carbonate is the most common of the carbonate group.
_Phosphates are not as common in occurrence as the other families of minerals. They are often formed when other minerals are broken down by weathering. They are often brightly colored.
_Mineraloid is the term used for those substances that do not fit neatly into one of these eight classes. Opal, jet, amber, and mother of pearl all belong to the mineraloids.
CLAY. Kaolinite: Al2Si2O5(OH)4: layered silicate mineral, with one tetrahedral sheet of silica (SiO4) linked through oxygen atoms to one octahedral sheet of alumina (AlO6) octahedra. From the following equation for kaolinite formation 2 Al(OH)3 + 2 H4SiO4 ? Si2O5 + 2 Al(OH)3 + 5 H2O it can be seen that five molecules of water must be removed from the reaction for every molecule of kaolinite formed. Alternating wet and dry conditions on the transition of allophane into kaolinite has been stressed.
GRANITE. Composition of Common Igneous Rocks
geology.com/rocks/pictures/granitoid-rocks.gifgeology.com/rocks/granite.shtmlGranite/Rhyolite: orthoclase-feldspar, quartz, mica, amphibole, plagioclase-feldspar
Diorite/Andesite: (o-feldspar, quartz,) mica, amphibole, p-feldspar, pyroxene
Gabbro/Basalt: (mica, amphibole,) p-feldspar, pyroxene, olivine
Peridotite: pyroxene, olivine
GRANITE. Feldspars (KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8) are a group of rock-forming tectosilicate minerals that make up about 41% of the Earth's continental crust by weight. Feldspars crystallize from magma as veins in both intrusive and extrusive igneous rocks and are also present in many types of metamorphic rock. Rock formed almost entirely of calcic plagioclase feldspar (see below) is known as anorthosite. Feldspars are also found in many types of sedimentary rocks.
_three endmembers:
potassium feldspar (K-spar) endmember KAlSi3O8
albite endmember NaAlSi3O8
anorth[os?]ite endmember CaAl2Si2O8
_alkali feldspars are:
orthoclase (monoclinic)[10] KAlSi3O8
sanidine (monoclinic)[11] (K,Na)AlSi3O8
microcline (triclinic)[12] KAlSi3O8
anorthoclase (triclinic) (Na,K)AlSi3O8
.barium feldspars:
celsian BaAl2Si2O8
hyalophane (K,Ba)(Al,Si)4O8
_plagioclase feldspars (percent anorthite in parentheses):
albite (0 to 10) NaAlSi3O8
oligoclase (10 to 30) (Na,Ca)(Al,Si)AlSi2O8
andesine (30 to 50) NaAlSi3O8—CaAl2Si2O8
labradorite (50 to 70) (Ca,Na)Al(Al,Si)Si2O8
bytownite (70 to 90) (NaSi,CaAl)AlSi2O8
anorthite (90 to 100) CaAl2Si2O8
.6/8/17) 1:12am)
Rock Density (g/cm^3)
Coal 1.1 - 1.4
Halite 2.16
Graphite 2.23
Limestone 2.5av 2.3 - 2.7
Sandstone 2.5 2.2 - 2.8
Shale 2.6 2.4 - 2.8
Kaolinite 2.6
Feldspar 2.65 2.5 - 2.8
Quartz 2.65
Calcite 2.71
Gypsum 2.3 - 2.8
Rhyolite 2.4 - 2.6 quartz plagioclase sanidine (+?hornblende biotite)
Marble 2.4 - 2.7 calcite (+?clays micas quartz pyrite rust graphite)
Rock salt 2.5 - 2.6 halite
Andesite 2.5 - 2.8 plagioclase feldspars (+?biotite pyroxene amphibole)
Mica schist 2.5 - 2.9 quartz mica(=biotite or muscovite) (+?...)
Granite 2.6 - 2.7 feldspar quartz mica amphibole
Quartzite 2.6 - 2.8 quartz (+rust +?zircon rutile magnetite)
Gneiss 2.6 - 2.9 mafic(=shale=mica) felsic(=sandstone=quartz)
Illite 2.6 - 2.9 muscovite feldspar
Diabase 2.6 - 3.0 plagioclase augite (+?olivine magnetite ilmenite)
Chlorite 2.6 - 3.3
Slate 2.7 - 2.8 quartz muscovite/illite (+?biotite chlorite hematite ......................... pyrite)
Gabbro 2.7 - 3.3 pyroxene plagioclase (+amphibole olivine)
Talc 2.7 - 2.8
Dolomite 2.8 - 2.9
Basalt 2.8 - 3.0
Diorite 2.8 - 3.0 plagioclase feldspar amphibole (+...)
Biotite Mica 2.8 - 3.4
Hornblende 2.9 - 3.4
Tourmaline 3.0 - 3.2
Fluorite 3.18
Apatite 3.1 - 3.2
Peridotite 3.1 - 3.4 olivine (+...)
Olivine 3.3 - 4.3
Garnet 3.5 - 4.3
Sphalerite 3.9 - 4.1
Pyrite 5.02
Magnetite 5.18
Hematite 5.26
Copper 8.9
Gold 19.32
Iridium 22.42
-------------------------------
g/cc; Rock; ---- Range; - Min.Comp; --- Elem.Comp.
1.25 Coal ------ 1.1-1.4 -------------- -Car
2.16 Halite ---- ....... -------------- Clo-So
2.23 Graphite -- ....... -------------- -Car
------------------------
2.5 Limestone -- 2.3-2.7 -------------- Cal-Car----------Ox
2.5 Sandstone -- 2.2-2.8 --------------
2.6 Shale ------ 2.4-2.8 --------------
------------------------
2.6_ Kaolinite - ....... -------------- -----------------AlSilOxHO
2.45 Gypsum ---- 2.3-2.8 -------------- Cal-So-----------OxHO
2.5_ Rhyolite -- 2.4-2.6 qz pla fel
2.55 Marble ---- 2.4-2.7 calcite ------ Cal-Car----------Ox
2.55 RockSalt -- 2.5-2.6 halite ------- Clo--------------So
.... Plagioclase ....... pla ---------- (Cal/So)---------AlSilOx
2.65 Feldspar -- 2.5-2.8 pla fel ------ (Cal/Pot/So)-----AlSilOx
2.65 Quartz ---- ....... qz ----------- -----------------SilOx
2.71 Calcite --- ....... calcite ------ Cal-Car----------Ox
2.65 Andesite -- 2.5-2.8 pla fel/horn
2.65 Granite --- 2.6-2.7 fel qz mica amp
2.7_ MicaSchist- 2.5-2.9 qz mica
.... Mica ------ ....... mica --------- Cal(Fe/Mg+)------(Al/Sil+)Ox(Flo/HO)
.... Mica ------ ....... mica --------- Pot(Fe/Mg+)------(Al/Sil+)Ox(Flo/HO)
.... Mica ------ ....... mica --------- -So(Fe/Mg+)------(Al/Sil+)Ox(Flo/HO)
.... Hornblende- ....... horn --------- CalPot(Fe/Mag/Al)-AlSilOxHO
.... Hornblende- ....... horn --------- CalSo(Fe/Mag)----AlSilOxHO
.... Hornblende- ....... horn --------- Cal(Fe/Mag/Al)---(Al/Sil)Ox(Flo/HO)
.... Hornblende- ....... horn --------- -So(Fe/Mag)------(Al/Sil)Ox(Flo/HO)
.... Amphibole-- ....... amp ---------- CalSo(Fe/Mag/Al)-(Al/Sil)OxHO
2.7_ Quartzite - 2.6-2.8 qz+
2.75 Gneiss ---- 2.6-2.9 qz mica
.... Muscovite - ....... mica
2.75 Illite ---- 2.6-2.9 mus fel
2.75 Slate ----- 2.7-2.8 qz mus fel+
2.75 Talc ------ 2.7-2.8 -------------- -Mag-------------SilOxHO
2.8_ Diabase --- 2.6-3.0 pla aug+
.... Augite ---- ....... aug ---------- -Mag-------------(Si/Al)Ox
2.85 Dolomite -- 2.8-2.9 -------------- Cal-MagCar-------Ox
2.95 Chlorite -- 2.6-3.3 -------------- (Nic/Fe/Man/Mag)-AlSilOxHO
2.9_ Basalt ---- 2.8-3.0 -------------- -MagSo-----------AlSilOx
2.9_ Diorite --- 2.8-3.0 -------------- CalPot(Fe)-MagSo-AlSilOxHO
3.0_ Gabbro ---- 2.7-3.3 pyro pla+
3.1_ BiotiteMica 2.8-3.4 -------------- Pot-Mag----------AlSilOxHO(Flo)
3.1_ Tourmaline- 3.0-3.2 -------------- -SoLi------------AlSilOxHO
3.15 Hornblende- 2.9-3.4 -------------- Cal(Fe/Mag)-So---AlSilOxHO
3.18 Fluorite -- ....... -------------- Cal--------------Flo
3.15 Apatite --- 3.1-3.2 -------------- CalFos(Clo/Flo)--Ox(HO)
3.25 Peridotite- 3.1-3.4 -------------- -Mag-------------SilOx
3.8_ Olivine --- 3.3-4.3 -------------- -Mag-------------SilOx
3.9_ Garnet ---- 3.5-4.3 -------------- -Mag-------------AlSilOx
4.0_ Sphalerite- 3.9-4.1 -------------- Zin--------------Sul
5.02 Pyrite ---- ....... -------------- Fe---------------Sul
5.18 Magnetite - ....... -------------- Fe---------------Ox
5.26 Hematite -- ....... -------------- Fe---------------Ox
8.9_ Copper ---- ....... -------------- Cop
19.32 Gold ----- ....... -------------- Go
22.42 Iridium -- ....... -------------- Ir
Gneiss: A common cause of the banding is the subjection of the protolith (the original rock material that undergoes metamorphism) to extreme shearing force, a sliding force similar to the pushing of the top of a deck of cards in one direction, and the bottom of the deck in the other direction.
.12/24/14) 8:14PM)
Basalt = Pyroxene (Augite) + Plagioclase + Olivine + glass?
----------------
Granite = Feldspar + Quartz + Mica + Amphibole
----------------Sil/Al)MagOx
Feldspar = Microcline/Orthoclase or Albite or Anorthite:
----------------Pot/So/Cal)AlSilOx
70% Shale = Clay + Quartz + Calcite
15% Sandstone = Quartz + Feldspar
15% Limestone = Calcite + Aragonite
-----
Kaolinite - Al2Si2O5(OH)4
Quartz ---- SiO2
Mica ------ X2Y4-6Z8O20(OH,F)4
X: K/Na/Ca/(Ba/Rb/Cs)
Y: Al/Mg/Fe/(Mn/Cr/Ti/Li..)
Z: Si/Al(+?Fe/Ti)
Amphibole - NaCa2(Mg,Fe,Al)5(Al,Si)8O22(OH)2
-----
Formula Mineral Identify?
C Graphite, Yes HS 8
NaCl Halite, Yes HS 8
NaAlSi3O8 =Plagioclase: Albite, Yes HS/TS 3
Na(Al,Si)4O8 Plagioclase --- HS/TS 3
Na(AlSi)O4 Nepheline --- HS/TS 3
Na3K(AlSiO4)4 Nepheline, GCom HS/TS 3
Na8Al6Si6O24Cl2 Sodalite, GCom HS 3
Na2Ca4Al10Si26O72•30H2O Stilbite, GCom HS 3
Na2(Mg3Al2)Si8O22(OH)2 Glaucophane, Yes HS/TS 5,4
NaLi3Al6(Si6O18)(BO3)4(OH)5 Tourmaline, GCom HS/TS 4,5
NaMg3Al6(Si6O18)(BO3)4(OH)5 Tourmaline, GCom HS/TS 4,5
NaAl3Al6(Si6O18)(BO3)4(OH)5 Tourmaline, GCom HS/TS 4,5
NaFe3Al6(Si6O18)(BO3)4(OH)5 Tourmaline, GCom HS/TS 4,5
Na,Ca,(Mg,Fe),Al,Si,O,(OH) Hornblende --- HS/TS 4
Na2–3(Mg,Fe,Al)5(Al,Si)8O22(OH,F)2 Hornblende, GCom HS/TS 5
NaCa2(Mg,Fe,Al)5(Al,Si)8O22(OH)2 Amphibole
X2Y4-6Z8O20(OH,F)4 Mica
X=(Na,K,Ca,Ba,Rb,Cs) Y=(Li,Mg,Al,Ti,Cr,Mn,Fe,etc.) Z=(Al,Si,Ti,Fe3+)
Mg2SiO4 Olivine, Yes HS/TS 6
Mg2Si2O6 Enstatite, Yes HS/TS 5,4
Mg3Si4O10(OH)2 Talc, Yes HS/TS 4,5
Mg3Si2O5(OH)4 Serpentine, GCom HS 4,5
Mg6Si4O10(OH)8 Chlorite, GCom HS/TS 4,5
Mg3Al2Si3O12 Garnet, Yes HS/TS 6
Mg2(Si,Al)2O6 Augite, GCom HS/TS 5
Mg2(Al,Fe3+)3Al2O(SiO4)2(OH)5 Chloritoid, GCom HS/TS 6
Al2O3 Corundum, Yes HS 7
Al2SiO5 Andalusite, Yes HS/TS 6
Al2SiO5 Sillimanite HS/TS 6
Al2SiO5 Kyanite, Yes HS/TS 6
Al2SiO5 Sillimanite, Yes Hs/TS 6
Al2(Si,Al)2O6 Augite, GCom HS/TS 5
Al2Si2O5(OH)4 Kaolinite, GCom HS 4,5
Al2Be3Si6O18 Beryl, Yes HS 4,5
SiO2 Quartz --- HS/TS 3
SiO2•nH2O Opal, Yes HS 3
S Sulfur, Yes HS 8
KAlSi3O8 Microcline, Yes HS/TS 3
KAlSi3O8 Orthoclase, Yes HS/TS 3
KAlSi3O8 Sanidine, Yes HS 3
K(AlSi)O4 Nepheline --- HS/TS 3
K,Ca,(Mg,Fe),Al,Si,O,(OH) Hornblende --- HS/TS 4
KAl2(AlSi3)O10(OH)2 Muscovite, Yes HS/TS 4,5
KMg3(AlSi3)O10(OH)2 Biotite, Yes HS/TS 4,5
KFe3(AlSi3)O10(OH)2 Biotite, Yes HS/TS 4,5
Ca2(CO3)2 Calcite, Yes HS/TS 7
Ca2(CO3)2 Aragonite, Yes HS 7
CaMg(CO3)2 Dolomite, Yes HS 7
CaMgSi2O6 Diopside, Yes HS/TS 5,4
CaSO4•2H2O Gypsum, Yes HS 7
Ca2Si2O6 Wollastonite, Yes HS 5,4
Ca(Al,Si)4O8 Plagioclase --- HS/TS 3
CaAl2Si2O8 =Plagioclase: Anorthite, Yes HS/TS 3
Ca2(Fe,Mg)5Si8O22(OH)2 Actinolite Yes HS/TS 5
Ca3Al2Si3O12 Garnet, Yes HS/TS 6
Ca,(Mg,Fe,Al),Si,O Augite --- HS/TS 4
Ca2(Si,Al)2O6 Augite GCom HS/TS 5
CaF2 Fluorite, Yes HS 8
Ca5(PO4)3(OH,F,Cl) Apatite, Yes HS/TS 7
Ca2Al2(Al,Fe3+)OOH(Si3O11) Epidote GCom HS/TS 5,4
Ca2–3(Mg,Fe,Al)5(Al,Si)8O22(OH,F)2 Hornblende GCom HS/TS 5
Mn3Al2Si3O12 Garnet, Yes HS/TS 6
Mn2(Al,Fe3+)3Al2O(SiO4)2(OH)5 Chloritoid, GCom HS/TS 6
Fe2O3 Hematite, Yes HS 7
Fe3O4 Magnetite, Yes HS 7
FeS2 Pyrite, Yes HS 8
Fe-S Pyrrhotite, Yes HS 8
Fe2SiO4 Olivine, Yes HS/TS 6
Fe3Al2Si3O12 Garnet, Yes HS/TS 6
Fe6Si4O10(OH)8 Chlorite, GCom HS/TS 4,5
(Fe2,3)2(Si,Al)2O6 Augite GCom HS/TS 5
Fe2Al9O(SiO4)5(OH)2 Staurolite GCom HS/TS 6
Fe2+,Mg,Mn,Al,Si,O,(OH) Chloritoid HS/TS 6
Fe2+2(Al,Fe3+)3Al2O(SiO4)2(OH)5 Chloritoid GCom HS/TS 6
FeTiO3 Ilmenite, Yes HS 7
FeCr2O4 Chromite, Yes HS 7
FeAsS Arsenopyrite, Yes HS 8
Cu Copper, Yes HS 8
Cu2(CO3)(OH)2 Malachite, GCom HS 7
Cu3(CO3)2(OH) Azurite, GCom HS 7
CuFeS2 Chalcopyrite, Yes HS 8
Cu5FeS4 Bornite, Yes HS 8
ZnS Sphalerite, Yes HS 8
Sb2S3 Stibnite, Yes HS 8
MoS2 Molybdenite, Yes HS 8
HgS Cinnabar, Yes HS 8
PbS Galena, Yes HS 8
-----------
Sea floor sediment:
- Terrigenous sediment is derived from land and usually deposited on the continental shelf, continental rise, and abyssal plain. It is further contoured by strong currents along the continental rise.
- Pelagic sediment is composed of clay particles and microskeletons of marine organisms that settle slowly to the ocean floor. Some of these organic sediments are called calcareous or siliceous “oozes” because they are so thick and gooey. The clay component (or sometimes volcanic ash) is generally carried from land by wind and falls on the surface of the ocean. Pelagic sediment is least abundant on the crest of midoceanic ridges because of the active volcanism.
- Hydrogenous sediments are rich with minerals, such as manganese nodules, that precipitate from seawater on the ocean floor.
Very Little Sediment on the Seafloor
answersingenesis.org/geology/sedimentation/1-very-little-sediment-on-the-seafloor/- Every year water and wind erode about 20 billion tons of dirt and rock debris from the continents and deposit them on the seafloor. Most of this material accumulates as loose sediments near the continents. Yet the average thickness of all these sediments globally over the whole seafloor is not even 1,300 feet (400 m).
- Some sediments appear to be removed as tectonic plates slide slowly (an inch or two per year) beneath continents. An estimated 1 billion tons of sediments are removed this way each year. The net gain is thus 19 billion tons per year. At this rate, 1,300 feet of sediment would accumulate in less than 12 million years, not billions of years.
- In the latter stages of the year-long global Flood, water swiftly drained off the emerging land, dumping its sediment-chocked loads offshore. Thus most seafloor sediments accumulated rapidly about 4,300 years ago.
- Those who advocate an old earth insist that the seafloor sediments must have accumulated at a much slower rate in the past. But this rescuing device doesn’t “stack up”! Like the sediment layers on the continents, the sediments on the continental shelves and margins (the majority of the seafloor sediments) have features that unequivocally indicate they were deposited much faster than today’s rates. For example, the layering and patterns of various grain sizes in these sediments are the same as those produced by undersea landslides, when dense debris-laden currents (called turbidity currents) flow rapidly across the continental shelves and the sediments then settle in thick layers over vast areas. An additional problem for the old-earth view is that no evidence exists of much sediment being subducted and mixed into the mantle.
Seafloor Sedimentary Rock
www.edu.pe.ca/southernkings/sedimentaryec.htm- Sedimentary rock covers about three fourths of the land area, and most of the ocean floor.
- In some places, such as the mouths of rivers, the sedimentary rock is 12,000 meters thick.
www.icr.org/research/index/researchp_lv_r01DSDP extracted cores from 624 sites on the ocean floors of the globe. Cores from most of these sites showed only recent sediments from the Tertiary and Quaternary periods. Of the 624 total sites only 186 contained sediments from the Cretaceous period or earlier. This means that the ocean floor is relatively young compared to the continents. The mean thickness of the sediments above the Cretaceous/Tertiary boundary (as identified by DSDP based on fossils, paleo-magnetics stratigraphy, etc.) for all 186 sites was 322 meters, with a standard deviation of 273 meters. Figure 1 shows a histogram of sediment depth for the 186 sites. The mean thickness of the sediments reported below the Cretaceous/Tertiary boundary was about 400 meters in the Atlantic Ocean and 100 meters in the Pacific Ocean.
www.thunderbolts.info/forum/phpBB3/viewtopic.php?f=4&t=4366&start=15#p18164- The Seafloors are mostly Basalt, about 3 miles thick, which cooled and solidified slowly, so the grains are microscopic. The Continents are mostly Granite, which is identical to Basalt, except the grains are larger, indicating that Granite cooled and solidified quickly. Gentry's radio-halo Inclusions in Granite, with parentless Po, also indicate quick solidification of the Granite Continents. It seems likely that Granite should initially have covered the entire Earth, because the outer layer would have been exposed to colder temperature, where solidification/crystallization would occur rapidly.
- * Conventional science seems to contend that granite cooled slowly, which allowed it to form large grains, whereas basalt cooled quickly, so it had less time to form large grains. My theory above said the opposite, partly because I got mixed up.
* However, Robert Gentry's parentless Polonium halo evidence still holds, indicating that the basement granite rocks formed quickly.
* So now the question is, Can larger grains form quickly and smaller grains form slowly?
COMPOSITION AND STRUCTURE OF OCEANIC CRUST
www.indiana.edu/~g105lab/1425chap13.htmwww.indiana.edu/~g105lab/images/gaia_chapter_13/ocean_crust.jpg- The oceanic crust is not simply a pile of basalt, but can be subdivided into several distinct layers, that form in response to the processes operating at a midoceanic ridge.
- The top layer (1.) consists of pelagic sediments that were deposited above the basalts of the oceanic crust. The second layer (2.) consists of lavas that were extruded onto the ocean floor at the spreading center. These lavas are called pillow basalts, because of the way they appear in cross-section. The molten basalt is extruded onto the ocean floor through fractures (extension), and as soon as the molten material comes in contact with seawater it will cool down and solidify. The next batch of lava will come out to the side of the first one, and also will solidify, etc. We will slowly pile up small batches of magma, that in their geometric arrangement are not unlike a pile of sausages, or squirts out of a toothpaste tube. In cross section we will have mainly elliptical cross-sections (pillow shape), thus the name pillow basalt. The surface topography of this layer is irregular and rough. The third layer (3.) consists essentially of complexly cross-cutting, near vertical basaltic dikes, which are the feeder channels for the pillow basalts. They form as fractures at the spreading center (highest extensional stress), and finally fill up with basalt and become part of the sheeted dike complex as they move away from the spreading center. The fourth layer (4.) consists of the magma chambers that feed the dikes of layer three, and these leftover magma chambers are filled by the plutonic equivalent of basalt, gabbro. The magma itself originated by partial melting in the mantle below the spreading center (higher heatflow, rising of accumulating melt). Below that layer is the mantle (asthenosphere), consisting of peridotite.
----------
Supercontinent from the Moon?
Moon Minerals Formation Environment
While most of the minerals in Moon rocks are found on Earth, they were formed in very different environments. Moon rock shows evidence of formation in an extremely dry setting, with low gravitational influence and very little surrounding oxygen.
Lunar rocks are anhydrous -- they contain no water and there is no evidence of the presence of water in their formation. This is not true of seabed basalts.
Differences Between Moon & Earth Minerals
We have now discovered small differences between the Earth and the Moon. [] The difference [] could be explained by material absorbed by the Earth after the Moon formed
Lunar Composition
csep10.phys.utk.edu. Geologically, the Lunar surface material has the following characteristics:
1. The Maria are mostly composed of dark basalts, which form from rapid cooling of molten rock from massive lava flows.
2. The Highlands rocks are largely Anorthosite, which is a kind of igneous rock that forms when lava cools more slowly than in the case of basalts. This implies that the rocks of the Maria and Highlands cooled at different rates from the molten state and so were formed under different conditions.
3. Breccias, which are fragments of different rocks compacted and welded together by meteor impacts, are found in the Maria and the Highlands, but are more common in the latter.
4. Lunar Soils contain glassy globules not commonly found on the Earth. These are probably formed from the heat and pressure generated by meteor impacts.
- Anorthosites that are common in the Lunar Highlands are not common on the surface of the Earth [except in] The Adirondack Mountains and the Canadian Shield. [] They form the ancient cores of continents on the Earth.
Differences
meteorites.wustl.edu. lunar rocks don't contain carbonate minerals or abundant quartz, as do most terrestrial sedimentary rocks. [] no known lunar rock [looks like] sedimentary rock. [] Unlike some terrestrial conglomerates, which resemble lunar breccias, the matrix of lunar breccias is as hard as the clasts. [] Nearly all the aluminum is in plagioclase and nearly all the iron and magnesium are in pyroxene, olivine, and ilmenite. [] Most Earth rocks plot below the lunar line because they contain quartz or calcite, which have essentially zero concentrations of FeO, MgO, and Al2O3. [] On the Moon [] there are no rocks rich in quartz or other silica polymorphs* [] among nearly all common lunar rocks calcium concentrations vary by a factor of 2, from 10% to 20% as calcium oxide (CaO).
Oxygen Differences
www.scientificamerican.com. Moon rocks contain a tiny bit more of the rare isotope oxygen-17 than do the rocks on Earth. [] They found 12 parts per million more oxygen-17 in the Moon rocks as opposed to the Earth rocks. [] the body that triggered the Moon-forming impact, which some scientists call Theia, may have been chemically similar to a class of meteorites called enstatite chondrites. Those are similar enough to Earth, at least in terms of oxygen, that Theia wouldn’t have left a major imprint in the Moon’s chemistry
Oxygen
www.wired.com. Previous research has established that the oxygen isotope composition of lunar samples is indistinguishable from that of Earth. [] Earth may have exchanged oxygen gas with the magma disk that later formed the Moon. [] The proportion of 50Ti to 47Ti is [] effectively the same as Earth’s and different from elsewhere in the solar system. [] it’s unlikely Earth could have exchanged titanium gas with the magma disk because titanium has a very high boiling point. [] One possibility is that a glancing blow from a passing body left Earth spinning so rapidly that it threw some of itself off into space. []
Volatiles
www.space.com. Water (made of volatile elements hydrogen and oxygen) is the most common volatile species on Earth. [] [There are] small quantities of volatile elements, and fluorine, in tiny mineral droplets of lunar volcanic glass called spherules. [] some lunar minerals are [possibly] as rich in volatile elements as their terrestrial counterparts. [] [Some lunar] apatite crystals [] are very similar to those apatite crystals that grew from 'wet' magmas on Earth
Titanium Differences
www.lpi.usra.edu. when one looks at the Moon in the night sky, the dark areas are basalt. The basalts found at the Apollo 11 landing site are generally similar to basalts on Earth and are composed primarily of the minerals pyroxene and plagioclase. One difference is that the Apollo 11 basalts contain much more of the element titanium than is usually found in basalts on Earth. The basalts found at the Apollo 11 landing site [] were formed from at least two chemically different magma sources.
Impacts
Moon rocks ejected by asteroid impacts have landed on Earth. [] one was found in Antarctica.
Impact Breccias
The heat and pressure of [] impacts sometimes fuses small rock fragments into new rocks, called breccias. []
Lunar Highlands Plagioclase
The lunar highlands are primarily a light-colored rock known as anorthosite, which consists primarily of the mineral plagioclase. It is very rare to find rocks on Earth that are virtually pure plagioclase.
