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ANSWER 72 TO 99UPLOAD TO SLIDE SHARE
• aaaaaaaaaaROCKEXAM aaaaaFELSIC PAGE 58
• THIS PLUS 3 OTHERS
• 1. SLIDE SHARE
• 2. GRADE LABS-9 OF THEM
• 3. PDF CHAPTER 4-EMAIL KIDS -2 (TWO) AT A TIME-J5
• 4. FINISH SEDIMENTARY-YOUR DONE
• 5.READ METAMORPHIC-GET PAID AT 5 AM
• Different igneous rocks are formed depending on the presence of different minerals and how fast the magma cools. Some igneous rocks include pumice, obsidian, and basalt. The rapid separation of the gases from lava produces pumice, a rock with large air spaces in it, similar to a sponge. The rapid cooling of lava produces obsidian and fine-grained rocks such as basalt.
Page 51
• 3.
• A.> i. crust has greater surface area
• ii. > crust cools faster –has no concealed center – a ball does!
• B. i. > plastic cools faster – does not hold heat like styrofoam
• ROCK IS BETTER INSULATOR
PAGE 51
• 3.
C. i. > Large cube 1 cm2
8 small cubes – approx 8 cm2-more area
C. ii. > Small cubes cool faster
C. iii. > small mass losses heat faster
Exercise 3 -52
• Phaneritic- course-cooled slowly-should have crystal-ions migrated slowly and formed crystals-nucleation possible
• Aphaneritic-fine ( cools fast! Less time for Na+ to migrate-no crystal formation
Exercise 3- page 52
• A) same rock material
• Regions close together-
• 1st area cooled fast and was not viscous
• 2nd area –cooled slow –and was very viscous
Exercise 3- page 52
• 3-D –shallow INTRUSIVE IGNEOUS ROCKS
• -have-fine course grains
• Than DEEP INTRUSIVE IGENOUS ROCKS
• SHALLOW-INTRUSIVE-finer!!!
• Deep-intrusive-not finer or course –from thick lava
Go right to excersice
• Felsic-dense spotty material to the left
• Intermediate
• Mafic –less dense percentages to the righ
Lets all go to the do now-we will come back to this
• Can use page 58 to complete this and hand directly in
Felsic
• white mica" (muscovite
• Quart
• K –feldspar
• biotite
FELSIC = fel-feldspar=sic-silica
• Light weight- low specific gravity
• Biotite, quartz and potassic feldspar
• Ligth colored
1. Microcline(K-Feldspar)
• Microcline(K-Feldspar)
j5----yes--4. muscovite-FELSIC
Mafic - “ma”---”fic”
• Comes from ferric-mag-Mg –magnesium
• Ferric-loves iron
• Less silica
• Calcium rich plagioclase
• High specific weight
• Fine grained
• Dark colored
TO THE LEFT-PAGE 58
• GRANITE PEGAMATITE
• RYOLITE PEGAMATITE
• PORPHRITIC GRANITE
• PORPHRITIC RYOLITE
– OBSIDIAN
– PUMICE
• RYOLITE TUFT
PAGE 52
• 4 (B)-3a pyroxene-slow cooling rate wihaphanetic –large cubesstyrofoam walls
• 4(B)-3b hornblende-aphanitic=fast, small cubes, plastic cups
• 4(B)-3c dark colored –fine grained –aphanitic– fast-small cubes-plastic cups
• 4(B)-3d-light colored –course grained-
• -slow cooling rate wih aphanetic –large cubesstyrofoam walls
Lava rock and pumice
• Porous igneous rock –bubbles have formed just as lava solidifies-the shape of the bubbles have been preserved in the lava
• This occurs as magma rises to the surface
• This is porous vesicular texture
Fragmental textures
• Due to pyroclastic debris
• Pyro –fire
• Clast-broken
• “large blocks or bombs”
• Have crystals formed before eruption
• Have tiny ash-pieces of rock inside
Exercise 5
• Which rock formed in ash fall?
• C. volcanic rock fragments in a very fined grained brown ash
• In pyroclastic flow?
• This would be (a) kalauea in Hawaii
• Finer grained-pyroclastic
Exercise 6
• Rapid-Fine grained –aphanitic-grains cannot be seen without magnification-rapid cooling general extrusive(above )
• Rapid-Pourous vesicular-spongy filled with large holes or small holes-rapid cooling followed by release of gas
Table 2 page 57
• Felsic-silca content-64%-75%-K-feldspar,Na-plagioclast-quartz
• Intermediate-silica content 52%-63% -ca-Na plagioclase, amphibole, pyroxene
Table 2 page 57
• Mafic -silca content-45%-57%-Ca-plagioclase, olivines and pyroxenes-aluminum –calcium-iron and magnesium
• Ultramafic-silca content-39%-44%-olivines and pyroxenes
• Have iron and magnesium
TO THE LEFT-PAGE 58
• GRANITE PEGAMATITE
• RYOLITE PEGAMATITE
• PORPHRITIC GRANITE
• PORPHRITIC RYOLITE
– OBSIDIAN
– PUMICE
• RYOLITE TUFT
Exercise 8
• Bowen’s reaction series
• Insight’s from melting experiments
• (a) plagioclase feldspar-minerals crystalize by cont and discontinuos process
• (b) pyroxene and amphibole-discontinuous reactions
• 8-B-this is unlikely-mineral with high melting points are ultra mafic and to the left-discontinuous
• Low melting points –simple melting-biotiteand Na-rich-feldspar –felsic igneous rocks
• Minerals now crystalize by all three types
• Simple-continuous-discontinuous
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