Rock Identification Lab Page 2

11. How   a re   m etamorphic   r ocks   c lassified?  

Foliated   o r   n on-­‐foliated  

 

12.

Metamorhpism   i s   a   p rocess   t hat   c hanges   o ne   t ype   o f   r ock   i nto   a nother.   C hoose   r ock   # 1   o r   1 2   a nd   i dentify   t he  

metamorphic   r ock   i t   c hanged   i nto.  

1   –   9  

12   -­‐   3  

13. What   i s   r ecrystallization?  

When   r ocks   a re   s ubject   t o   h eat   a nd   p ressure,   a s   t hey   c ool   t he   c rystals   m ay   c hange   i n   s ize   o r   c omposition  

 

 

14. What   d istinguishes   t he   t wo   m ain   t ypes   o f   i gneous   r ocks?   E xplain.   F ind   a n   e xample   o f   e ach   t ype:   _ ______   &   _ ______  

Where   t hey   a re   f ormed:   i ntrusive   o r   e xtrusive  

1   –   i ntrusive  

6   -­‐   e xtrusive  

 

 

15. What   a re   t he   5   d ifferent   t extures   o f   i gneous   r ocks?   W here   a re   t hey   f ormed?  

coarse   –   i ntrusive,   s low   c ooling  

fine   –   e xtrusive,   f ast   c ooling  

glassy   –   e xtrusive,   v ery   f ast   c ooling  

vesicular/porous   –   e xtrusive,   f ast   c ooling   ( gas   b ubbles)  

porphyritic   –   i ntrusive   a nd   e xtrusive,   s low   t hen   f ast  

 

16. Use   t he   k ey   t o   i dentify   t he   f ollowing   s edimentary   r ocks:   1 0,   1 4.   R ecord   y our   f indings   i n   t he   I D   c hart   f or   e ach.    

17. Use   t he   k ey   t o   i dentify   t he   f ollowing   i gneous   r ocks:   1 ,   6 .   R ecord   y our   f indings   i n   t he   I D   c hart   f or   e ach.  

18. Use   t he   k ey   t o   i dentify   t he   f ollowing   m etamorphic   r ocks:   3 ,   7 .   R ecord   y our   f indings   i n   t he   I D   c hart   f or   e ach.  

Analysis   a nd   C onclusion  

Which   t wo   r ocks   w ere   t he   e asiest   t o   i dentify?   W hy?  

 

Which   t wo   r ocks   w ere   t he   m ost   d ifficult   t o   i dentify?   W hy?  

 

How   d ifficult   w as   i t   t o   u se   t he   k ey   t o   c lassify   y our   r ock   s amples?   W hat   p roblems   d id   y ou   e ncounter?  

 

 

When   y ou   f ind   a   r ock   o n   y our   o wn,   w hat   s teps   c an   y ou   t ake   t o   i dentify   i t?