Lab/field assignment

1. Historical Geology: Central
California Coast
BY ANGELICA OCAMPO

2. Introduction:
In order to explain the evolution of Earth it will require the observation and
research of rocks, species, and oceans. In this presentation I examine and
observe rocks, oceans, and species. I will also identify the Law of Original
Horizontality and angular unconformity. This presentation will be based on
my exploration of the Central Coast, and more specifically the beauty of the
area of Montana De Oro.

3. Central Coast: Montana De Oro
Montana De Oro is located in the Central Coast and is one of the largest
state parks in California. It is known for its many formations of the
sedimentary rocks. It is near the “unstable western coast of this continent the
Pacific Plate” and grinds against the North American Plate. It has tilted
sedimentary layers and has lifted them above the sea. Sea level has changed
over the last 5-10 million years creating so much change. (California State
Parks and Central Coast State Parks Association. 2012)

4. Montana De Oro
(California State Parks and Central Coast
State Parks Association. 2012)

5. Miguelito Shale-
Sedimentary rock
• They formed about 5-6 million years ago.
• It is made of deposits when tiny fragments of once-
living organisms drifted to the bottom of the sea
and mixed with silt and sand.
• The mud became solid thick layers of diatomite,
clay porcellanite, dolomite, and chert. (California
State Parks and Central Coast State Parks
Association. 2012)

6. Nearshore Sediment
Budget
• Eroded basin lined by thin layer of rocks
• Nearshore sediment budget is the long term
sediment budget considers the input vs output.
• In this image it could be the output is exceeding as
the beach has a negative budget and is eroding.
(Monroe, J. S., & Wicander, R. 2015)

7. Limestone- Sedimentary
Rock
• Rocks located on the Bluff trail in Montana De Oro
State Park
• Limestone rock because of its light color and its
likely formation from precipitation of mineral
matter since it is so close to the coastline.
• Limestone is a sedimentary rock formed by
extraction of mineral matter from seawater (which
is right off the coast line) by organisms or by the
precipitation of the mineral calcite from seawater.
(Monroe, J. S., & Wicander, R. 2015)

8. Native Americans to Montana De Oro were called
Chumash, used rock residue as face paint.

9. Law of Original Horizontality
• This image at the California’s
Central Coast supports Nicolas
Steno principle of original
horizontality
• The sedimentary particles settle
from water from gravity,
sediments is deposited in
horizontal layers.
• 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)

10. Montana De Oro-Angular Uncomformity
• Angular uncomformity at Montana De
Oro
• This angular uncomformity seen here is
an erosional surface on tilted or folded
strata, which shows that younger strata
were deposited over it.
• 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)

11. Fossilferous Limestone-Biochemical Sedimentary Rocks
• This rock is right off the water, while there is some erosion, it does look as though there are
numerous fossil shells in it.
• Limestone does have skeleton and sea animals in several of them.
• These rocks are made up of calcite, dolostone with their crystalline texture. (Monroe, J. S., &
Wicander, R. 2015)

12. California Quail
• Here you see a California Quail in its habitat. Its habitat would be in coastal sagebrush.
• The female quail will typically hide in their nest which is on the ground at the base of shrubs and trees. (Sartore, J 2010)
• They are about 70% vegetarian. They are seed eaters, but will also eat leaves, flowers, and grains.
• 1-2 million years ago during the Late Pliocene or Early Pleistocene
• Their fossil record shows they are from the Odontophoridae family (California Quail. 2018)

13. Resources
 California State Parks and Central Coast State Parks Association. (2012).
Montaña de Oro State Park [Brochure]. Author. Retrieved June 20, 2018,
from https://www.parks.ca.gov/pages/592/files/MDO-Brochure-lr.pdf
 California Quail. (n.d.). Retrieved June 20, 2018
http://thewebsiteofeverything.com/animals/birds/Galliformes/Odontophor
idae/Callipepla-californica
 Monroe, J. S., & Wicander, R. (2015). The changing earth: Exploring
geology and evolution. Stamford, CT: Cengage Learning.
 Montaña de Oro State Park. (2018, June 19). Retrieved from
https://en.wikipedia.org/wiki/Montaña_de_Oro_State_Park
 Sartore, J. (2010, May 04). California Quail. Retrieved from
https://www.nationalgeographic.com/animals/birds/c/california-quail/