Lab/Field GEL103

1. Lab/Field
Assignment
California Central
Coast
BY RAUL CALDERON
GEL103
LAKE TAHOE COMMUNITY COLLEGE

2. INTRODUCTION:
 The nature of evolution is something that we as humans strive to learn
more about. California has an abundance of geological history and species’
of plants and animals that have evolved through time. In this presentation I
will be presenting what have analyzed and documented during my trip to
California’s Central Coast.

3. California Central
Coast Region
The Central Coast region extends from
Santa Cruz County south along
Monterey Bay and the isolated Big Sur
coast in Monterey County, to Morro Bay
and Avila in southern San Luis Obispo
County. (caseagrant,2018)

4. Central Coast
Salinas Rivers
• The Salinas river is currently held by
tectonic plate theory. (Lloyd,1982)
• It is also thought to have drained
prehistoric Lake Corcoran, which
once occupied much of what is now
California's Central Valley about
700,000 years ago.
• (Martin, 1999)

5. The Western
Gull (Larus
occidentalis)
• The Western Gull is a bird species
• It is theorized that all birds evolved
from Theropod Dinosaurs
• Theropod fossils show unique features
similar to modern day birds
• The ancestor of all living birds lived
sometime in the Late Cretaceous, and
in the 65 million years since
the extinction of the rest of the
dinosaurs, this ancestral lineage
diversified into the major groups of
birds alive today.

6. Central Coast Mountain Range
• The Southern Coast Ranges are mainly
composed of Sedimentary rocks
• in The Central Coast of California, Tectonic
forces and volcanism form the landscape
• Much of the continental crust that is now
California was derived or recycled from crust
that originally formed beneath the Pacific Ocean
as ocean crust. (Geologycafe,2018)
• By late Miocene time, the shoreline geometry of
southern California changed significantly as
mountain ranges began to rise along the
coastline (Geologycafe,2018)

7. Central Coast Rocks
The general classification for this
rock is sedimentary
It is a mudstone rock, it is formed
from the seafloor mud.
its is very light weight and is has a
sandy texture
The general classification for this
rock is sedimentary
It is a Siltstone rock
This rock is also very light weight
and has a sandy texture
However, this rock is rich in quartz
silt particles
The general classification for this
rock is Igneous
It is an Rhyolite which is a rounded
stream boulder
This rock has a smooth texture
with dents and holes imbedded
into its surface. This rock is very
dense and feel heavy.

8. Law of Original Horizontality
• The sequence of sedimentary
rock layers that are steeply
inclined from the horizontal
must have been tilted after
deposition and lithification
(Monroe, J. S., & Wicander, R.
2015)
• The law states that layers of
sediment were originally
deposited horizontally under
the action of gravity

9. Angular Unconformity
• The strata below the conformable
surface dip more steeply than those
above it, which could be seen here as
it is creating an angular rock.
(Monroe, J. S., & Wicander, R. 2015)
• Angular Unconformities are those
where an older package of sediments
has been tilted, truncated by erosion,
and than a younger package of
sediments was deposited on this
erosion surface.
• This Image shows erosion which
removes uplifted mountain range

10. References:
California Lakes, Rivers and Water Resources. (n.d.). Retrieved from https://geology.com/lakes-rivers-
water/california.shtml
Central Coast. (n.d.). Retrieved from https://caseagrant.ucsd.edu/project/discover-california-commercial-
fisheries/regions/central-coast
Salinas River (California). (2018, July 29). Retrieved from https://en.wikipedia.org/wiki/Salinas_River_(California)
Western Gull Overview, All About Birds, Cornell Lab of Ornithology. (n.d.). Retrieved from
https://www.allaboutbirds.org/guide/Western_Gull/overview
The origin of birds. (n.d.). Retrieved from https://evolution.berkeley.edu/evolibrary/article/evograms_06
Geology Cafe. (n.d.). Retrieved from http://geologycafe.com/
Monroe, J. S., & Wicander, R. (2015). The changing earth: Exploring geology and evolution. Stamford, CT: Cengage
Learning.
Law of Horizontality in Sediments Sedimentary Rock Processes. (n.d.). Retrieved from
http://geology.isu.edu/Alamo/rocks/law_horizontality.php