2. ANSWER 72 TO 99
UPLOAD 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

3. Take a box and the donow and hold
your exam in your hand
• Faith heart and skill (

4. • 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.

5. 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

6. 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

7. 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

8. 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

9. 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

10. Go right to excersice
• Felsic-dense spotty material to the left
• Intermediate
• Mafic –less dense percentages to the righ

11. Lets all go to the do now-we will come
back to this
• Can use page 58 to complete this and hand
directly in

12. Felsic
• white mica" (muscovite
• Quart
• K –feldspar
• biotite

13. FELSIC = fel-feldspar
=sic-silica
• Light weight- low specific gravity
• Biotite, quartz and potassic feldspar
• Ligth colored

14. 1. Microcline(K-Feldspar)
• Microcline(K-Feldspar)

15. j5--2. Milky quartz sample

17. j5----yes--4. muscovite-FELSIC

18. mafic
• Albite (plagioclase feldspar
• Olivine
• Augite --Pyroxene
• . Hornblende -amphilbole

19. Mafic - “ma”---”fic”
• Comes from ferric-mag-Mg –magnesium
• Ferric-loves iron
• Less silica
• Calcium rich plagioclase
• High specific weight
• Fine grained
• Dark colored

20. mafic--. Albite (plagioclase feldspar)

21. mafic==. Hornblende (amphibole)

22. mafic==. Augite (pyroxene)

23. mafic===Olivine
. Mg-rich olivine crystallizes
from magma

24. TO THE LEFT-PAGE 58
• GRANITE PEGAMATITE
• RYOLITE PEGAMATITE
• PORPHRITIC GRANITE
• PORPHRITIC RYOLITE
– OBSIDIAN
– PUMICE
• RYOLITE TUFT

25. PAGE 52
• 4 (B)-3a pyroxene-slow cooling rate wih
aphanetic –large cubesstyrofoam 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
cubesstyrofoam walls

26. 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

27. 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

28. 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

29. 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

30. • Rapid- glassy-shiny-looks like glass
• Slowly-pegamatic-course grained pegamatic-
Porphorytic-

31. More than two rates
• pyroclastic

32. Table 2 page 57
• Felsic-silca content-64%-75%-K-feldspar,Na-
plagioclast-quartz
• Intermediate-silica content 52%-63% -ca-Na
plagioclase, amphibole, pyroxene

33. 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

34. TO THE LEFT-PAGE 58
• GRANITE PEGAMATITE
• RYOLITE PEGAMATITE
• PORPHRITIC GRANITE
• PORPHRITIC RYOLITE
– OBSIDIAN
– PUMICE
• RYOLITE TUFT

35. Exercise 7
• Use the igneouse rock set –(your exam kit)
• Can just read through exam

36. Origin and evolution of magmas
• Decompression melting
• Flux melting
• Heat transfer melting

37. 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

38. • 8-B-this is unlikely-mineral with high melting
points are ultra mafic and to the left-
discontinuous
• Low melting points –simple melting-biotite
and Na-rich-feldspar –felsic igneous rocks
• Minerals now crystalize by all three types
• Simple-continuous-discontinuous

39. • 8c- from lowest
• Felsic-800oC-
• Intermediate-1050oC
• -mafic-1400oC
• -ultramafic-above -1400oC

40. • Partial melting
• Magmatic differentiation
• Assimilation
• Magma mixing
• 12 or 15
• 684 or 900