The document summarizes the geology of the San Joaquin Valley in California. It describes how the valley formed 65 million years ago between two mountain ranges. Sediment from the Sierra Nevada filled the basin. The document also discusses the evolution of pill bugs from sea creatures with gills to land-dwelling crustaceans. Spider plants are described as having adapted from South African origins to survive drought conditions through a tuberous root system. Samples of igneous granite, metamorphic slate, and sedimentary shale rocks found in Fresno are presented along with their identifying characteristics.

1. San Joaquin
Valley Geology
By Belgica Sanchez

2. Introduction
In this assignment I will demonstrate the geology of the San
Joaquin Valley. I did the assignment specifically in a city in the
San Joaquin Valley named Fresno. In the presentation I will be
showing a sedimentary, igneous, and metamorphic rock. I will
also be presenting the evolutionary geology of the San Joaquin
Valley, pill bug, and the spider plant.

3. San Joaquin Valley
San Joaquin Valley is a
basin, and it was
formed in front of a
mountain range.
This valley started to
form 65 million years
ago during the
Mesozoic.
When the San Joaquin
valley started forming it
was in between two
mountain ranges and it
was an inland sea.

4. San Joaquin Valley
• The sediment in the San Joaquin Valley comes from the Sierra
Nevada from its volcanic cover.
• All the sediment caused the San Joaquin Valley to become a
landlocked basin.
• The weather in the San Joaquin Valley varies from rainy
weather to very dry summers.

5. Pill Bugs Evolution (Rolli Polly)
• Pill Bugs ancestors came from the sea and explain why pill bugs have
gills. Their ancestors stopped living in seas millions of years ago. Pill bugs
have changed over time because they are now able to live on land.
However due to their gills they live in damp areas to avoid drying out and
suffocating.
• Pills bugs have adapted through evolution because their gills have
transformed into small lungs, and this is what allows them to be on dry
land although they still live on damp areas. Their gills have turned into
hollow branched structures.

6. Pill Bugs
• Pill bugs are not considered
insects, they are crustaceans.
• First pill bug fossil appeared
300 million years ago.
• These crustaceans eat plant
matter that dead or decaying.

7. Spider Plant Evolution
I took this photo in Fresno, CA
The spider plant grows its best in conditions
where there is low light, These plants like
sunlight but not directly. They are capable of
surviving in different types of weather. Spider
plants are from South and West African origin.
By the end of the 18 century, Spider Plants were
brought to Europe. This plant has evolved to
survive droughts by its tuberous root system
where it stores water. Spider plants are able to
spread very fast due to them being self
propagate.

8. Igneous Rock:
Granite
Quartz and feldspar are the minerals
found in granite. I identified this rock as
granite because it has light colors like
the minerals it contains and its texture
is very grainy, the minerals in the rock
are very visible as well. Igneous rock
like granite form when magma cools,
when they cool down they become
solid and crystalized. Igneous rock is
said to even be found on the moon. Picture from Fresno , CA

9. Metamorphic Rock:
Slate
I identified this rock as a metamorphic rock
because it has foliation. I say there is foliation in
this rock because it you look closely the rock look
like it is layered. What makes this metamorphic
rock, is heat and pressure. A lot of slate rocks are
shale rocks before they are slate rocks. Slate
rocks could be used for a majority of purposes,
an example is roofing because it is very durable.
The slate has mika flakes which are very small
minerals, the other two minerals are quarts and
chlorite.
I took this photo in Fresno,
California.

10. Sedimentary
Rock: Shale
Sedimentary rocks are formed through lithiation,
and this is when sediment becomes into a rock.
The shale rock is a clastic sedimentary rock. The
shale is made of both mud and clay, and in order
to be made compression needs to happen. I
considered this being a shale because it looks
very similar to the slate rock, but this shale rock
has layers that are barely noticeable, and it is
fragile. The shale can be found in rivers, lakes,
and even oceans. The shale along with many
other sedimentary rocks have a lot of information
on the history of life and Earth. This rock contains
clay minerals, quartz, iron oxides, and feldspars.
Photo from Fresno, California

11. I conducted the research in the city of Fresno, CA so I was not
successful at finding an angular unconformity. I think this is due
to Fresno not being surrounded by any big mountains or
mountains at all.
Unconformity

12. References
Intro to Geology of the San Joaquin Valley. (2021, June 1). San Joaquin Valley Geology.
http://www.sjvgeology.org/geology/
•
Chapter 10 The Great Central Valley. (2002). The Great Central Valley.
http://web.sonoma.edu/users/c/cannon/bio314chapter10.html
•
Cassidy, J. K. S. (2017, February 9). Pill bugs emerged from the sea to conquer the Earth. PBS NewsHour.
https://www.pbs.org/newshour/science/pill-bugs-emerged-sea-conquer-earth
•
The Pill Bug Diet: What Do Pill Bugs Eat? (2018, April 11). Orkin.Com. https://www.orkin.com/other/sowbugs/pillbugs/diet
•
Spider Plant 101: How to Care for Spider Plants. (2021, June 17). Bloomscape. https://bloomscape.com/plant-care-
guide/spider-plant/
•
P. (2020, May 2). ▷Spider Plant Care: A Helpful Guide (Propagation, Tips). Plantophiles. https://plantophiles.com/plant-
care/spider-plant/
•
Science, G. (2019, May 9). Shale. Geology Science. https://geologyscience.com/rocks/sedimentary-rocks/shale/
•
Shale | rock. (2021). Encyclopedia Britannica. https://www.britannica.com/science/shale
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