Flashcards in Test 2 Additional questions Deck (46)
What is meant by melange?
Term describing disruption of rock at subduction zone where one peice of crust is consumed by another
What is meant by Thrust fault?
When layers of rock collide and one layer is "thrusted" over the other resulting in the exposure of very old rock at the surface.
How was the omnicea formed?
Result of a plate collision where high pressures metamorphosed huge masses of granite and igneous rock.
whats a fault?
Where tectonic plates collide
Which reacts more violently to acid? Limestone or DOLOMITE?
What is meant by aphanitic?
What is meant by phaneritic?
What is meant by poryphyritic
Large crystals locked together with smaller crystals
What is meant by pyroclastic?
Composites of ejected volcanic fragments
What two groups are sedimentary rocks separated into?
explain the basis of differentiation
Clastic - composed of fragments from pre-existing material
Chemical Precipitate - minerals Precipitate out of water and settle to the bottom
What are the two types of micas?
Biotite - ferro magnesium
Muscovite - non ferro magnesium
Form at cooler temperatures
What are the two types of feldspar?
Orthoclase - Pink colour - non striated
Plagioclase - light or dark - striated
What is the texture of extrusive rocks?
What about intrusive?
Extrusive - Aphanitic
Intrusive - Phaneritic
What are the macro nutrients that come from the atmosphere?
Name some micro nutrients
Cl, B, Fe, Mn, Zn, Cu, Ni, Mo
What is andesite?
-Mainly plagioclase with other minerals like hornblende/pyroxine/biotite
What is Rhyolite?
-Similar to granite in composition (Quartz+Feldspar)
What is Basalt?
-Formed by quick cooling of magma at surface of earth
-Similar to Gabbro in composition (plagioclase/pyroxine/olivine)
What is Obsidian?
-forms when molten rock cools so rapidly that atoms do not have time to arrange themselves into crystal structure
What is Gabbro?
-similar composition to basalt but forms deeper (Plagioclase/augite/olivine)
What is Granite?
-Mainly quartz and feldspar
-Slow cooling of lava beneath earths crust
What is Diorite?
-similar to andesite but formed deeper in the earth
What is limestone?
-Formed primarily from the organic accumulation of shell and coral debris
What is conglomerate?
-Composed of compacted/lithified gravel size fragments of weathered material
What is Dolomite?
- Sedimentary chemical precipitate
- Similar to limestone but less reactive to acid
- Light colour
- reacts with acid
What is sandstone?
- Clastic sedimentary
- accumulation and lithification of sand sized particles
What is Shale?
-Accumulation and lithification of clay sizes weathering debris
-generally dark colour
What is siltstone?
-accumulation and lithification of silt sized weathering debris
Differentiate conglomerate and breccia
conglomerate has rounded fragments
breccia has angular fragments
-Both clastic sedimentary