Thursday, October 16, 2008

Schist





any of a class of crystalline metamorphic rocks whose constituent mineral grains have a more or less parallel or foliated arrangement

Xenolith



a rock fragment foreign to the igneous rock in which it is embedded

Bleached Zone



the area around the tourmaline in a cats paw.

Pegmatite



a coarsely crystalline granite or other high-silica rock occurring in veins or dikes

Pluton



any body of igneous rock that solidified far below the earth's surface

Solution pits- 33 4842 60 N 084 0886 00 W



when water gets in a low point of a rock and wears away at the rock and eventually forms a dent

Root Action- 33 4854 30 N 084 0922 70 W



Root Action is an example of Physical Weathering.

Lichens- 33 4832 60 N 34 0813 70 W


a primary community that contributes to chemical weathering

Wednesday, October 15, 2008

Gneiss- 33 4839 60 N 084 0881 20 W




Gneiss is a metamorphic rock that is generally made up of bands that differ in color and composition, some bands being rich in feldspar and quartz, others rich in hornblende or mica.

Dike- 33 4824 60 N 084 0821 20 W



Pluton that cuts across preexisting rocks and often forms when magma evades cracks in surrounding rock bodies

Physical Weathering- 33 4822 90 N 084 0822 10 W



The disintegration of earth material without undergoing a chemical change. Physical weathering results in increased surface area for chemical reactions to occur on.

Chemical Weathering- 33 4826 60 N 084 0823 40 W



Process in which rocks undergo changes in their compisition due to chemical reactions with agents such as acids water oxygen and carbon dioxide.

Exfoliation- 33 4822 10 N 084 0820 20 W



layers of rock being seperated

Quartz- 33 4823 60 N 084 0818 30 W



A very hard mineral composed of silica and SiO2.

Granite 33 4831 00 N 84 0812 60 W



a coarse-grained igneous rock composed chiefly of orthoclase and albite feldspars and of quartz, usually with lesser amounts of one or more other minerals, as mica, hornblende, or augite.

Felsic 33 4819 60 N 084 0820 00 W



Light colored igneous rocks that contain quartz and feldspars and have high silica contents

Phaneritic- 33 4827 40 N 84 0817 30 W


A rock in which the minerals are visible

Intrusion- 33 4825 20 N 084 084 0818 70 W



emplacement of molten rock in preexisting rock





















The emplacement of plutonic rock

Tuesday, October 14, 2008

Cat's Paw- 33 4836 50 N 084 0876 40 W



This is comprised of tourmaline and a bleached zone found on top of Stone Mountain.