Post on 06-Aug-2015
Basalt
I believe this rock to be basalt. Basalt is an igneous type of rock which is mostly dark gray to black in color. As you can see in the pictures, this rock is very shiny and fine-grained. It seems to contain abundant weathering and gas bubbles.
Phyllite
I believe this rock to be
phyllite due to its fine-
grained mica. It is a
foliate metamorphic rock.
It has a sort of glossy and
smooth feel and is
intermediate in grade
between slate and schist.
Sandstone
This rocks looks like sandstone. Sandstone is a clastic sedimentary rock that is made up of weathering debris. It has a light-gray to nearly white color appearance with a hint of brown. This rock is formed by the weathering of other rocks that are deposited by rivers, waves or winds.
Marble
I believe these two samples to
be marble. Marble is a non-
foliated metamorphic rock that
is produced of limestone as it
goes through metamorphism.
Marble is primarily composed
of calcium carbonate. It has a
soft, smooth surface and will
not scratch glass like quartzite.
Quartzite
These two samples appear to be quartzite rocks. Quartzite is a non-foliated metamorphic rock that is produced by the metamorphism of sandstone. It is composed primarily of quartz. It is a major metamorphic rock type from regional metamorphism.
References
Peck, D. (n.d.). The rock identification key . Retrieved from
http://www.rockhounds.com/rockshop/rockkey/index.html
Rocks: Igneous, metamorphic and sedimentary. Retrieved
from http://geology.com/rocks
Tarbuck, E., & Lutgens, F. (2008). Earth: An introduction to
physical geology. (9th ed.). Upper Saddle River, NJ: Pearson
Prentice Hall.
Note: Samples were taken from distinct areas in Firebaugh
such as the Maldonado Park and sites down near the San
Joaquin River.