Lake Tahoe was formed about 24 million years ago from faulting and uplifting of the Sierra Nevada block. It is a large alpine lake located in the Sierra Nevada mountains, with a deepest depth of 1,645 feet. The geology of the area includes formations such as basalt, marble, gneiss, magnetite, and pumice. Common trees and animals in the Lake Tahoe region include Jeffrey pine trees, Steller's jays, coyotes, and bears. The lake provides many recreational activities for visitors.

1. Geology Of Lake Tahoe
GEO 103
PROF. MARK LAWLER
BY SAUL JIMENEZ

2. Introduction
- Lake Tahoe was formed from faulting
- About 24 million years ago the Sierra Nevada block
was formed by uplifting
- Two principal faults evolved and uplifted blocks
created the Carson Range on the east and the Sierra
Nevada on the west
- Highest peaks of the Lake Tahoe Basin that formed
during this process were Freel Peak at 10,891 ft ,
Monument Peak at 10,067 ft (present day Heavenly
Valley Ski Area), Pyramid Peak at 9,983 ft and Mt.
Tallac at 9,735 ft
- General John C. Fremont's discovered the lake in
1844

3. Lake Tahoe - Present
- Modern Lake Tahoe was shaped and landscaped by the
scouring glaciers during the Ice Age a million or more years ago
- Many streams flow into Lake Tahoe, but the lake is drained
only by the Truckee River, which flows northeast through Reno
and into Pyramid Lake in Nevada
- Lake Tahoe is the third deepest lake in North America and the
tenth deepest in the world
- The lake is 22 miles in length and 12 miles wide with
approximately 72 miles of shoreline
- Its greatest measured depth is 1,645 feet
- The average depth of the lake is 1,000 feet
- Major recreational activities within the basin include casino
gaming in Nevada, alpine and cross-country skiing, golfing,
water sports, hiking, fishing, camping, and bicycling

4. Jeffrey Pine (Pinus jeffreyi)
- Most common tree found in the Tahoe basin
- Mainly found in California, but also in the westernmost
part of Nevada, southwestern Oregon, and northern Baja
California
- It’s a large coniferous evergreen tree with a massive trunk
- The bark is generally reddish brown with narrow plates
between deep fissures
- It can live up to 500 years
- It can grow to a height of 180 feet with trunks of up to 7
feet in diameter
- It is named in honor of its botanist documenter John
Jeffrey

5. Steller’s Jay (Cyanocitta stelleri)
- Native to western North America
- Steller’s Jays are large songbirds with large heads,
chunky bodies, rounded wings, and a long, full tail
- They are intelligent, inquisitive and noisy
- They are mainly found in evergreen forests of
western North America, at elevations of 3,000-
10,000 feet (lower along the Pacific coast)
- These birds are often seen in campgrounds, picnic
areas, parks, and backyards
- They are omnivores and their diet consists of
seeds, nuts, berries, and fruits
- Animal-matter portion of food consists of bird eggs
and nestlings, invertebrates, suet, small rodents,
reptiles, and carrion

6. Steller’s Jay More Facts
Where these birds are found year-round
- Migration occurs in the Fall and Spring
- Have expanded into a wider variety of
habitats within the past 20 years and are now
more common in towns and cities than they
previously were
- Adults are quiet and secretive while nesting,
but become noisy and aggressive if nest is
threatened

7. Coyote
- These animals are found a lot in Tahoe
- Its ancestors came from the gray wolf, 1-2 million years ago
- Coyote males average from 18–44 lbs. and females average 15–
40 lbs.
- Theory suggests that the coyote evolved in North America during
the Pleistocene epoch 1.81 million years ago
- The coyote mates between February and April
- A female will pick a mate they will normally mate for life
- Two months after mating, the female gives birth to on average 6
pups
The pups are weaned when they are about a month old
- They can almost eat anything, they like to hunt rabbits, rodents,
fish, frogs, and even deer
- They like eating insects, snakes, fruit, grass, and carrion

8. Igneous - Pumice
- A volcanic rock that consists of highly vesicular
rough textured volcanic glass, which may or may
not contain crystals
- Pumice is a type of extrusive volcanic rock,
produced when lava with a very high content of
water and gases
- The only rock that floats on water
- Used to make lightweight construction materials
such as concrete block and concrete

9. Metamorphic - Gneiss
- A common and widely distributed type of rock
formed by high-grade regional metamorphic
processes from pre-existing formations that were
originally igneous or sedimentary rocks
- The color of the rock is variable generally
alternating lighter and darker sub-parallel
discontinuous bands
- Hard rock with medium grain size and can see
crystals
- Gneiss is a product of regional metamorphism
- This is a type of metamorphism which is associated
with mountain building

10. Igneous - Basalt
- Very common igneous rock
- Rock formed from the rapid cooling of basaltic lava
exposed at or very near the surface of a planet or
moon
- It is most commonly crushed for use as an
aggregate in construction projects
- Basalt is usually black or dark gray
- It is composed of mineral grains which are mostly
indistinguishable to the naked eye

11. Mineral - Magnetite
- One of the three common naturally occurring iron
oxides (chemical formula Fe3O4)
- Magnetite is the most magnetic of all the naturally
occurring minerals on Earth
- Magnetite is sometimes found in large quantities
in beach sand and found in California and the west
of New Zealand
- Magnetite is best known for its property that it is
strongly attracted to magnets

12. Metamorphic - Marble
- Non-foliated metamorphic rock composed of
recrystallized carbonate minerals
- It is used for sculptures and for building
- Marble is usually a light-colored rock
- Marble of extremely high purity with a bright
white color
- Being composed of calcium carbonate, marble will
react in contact with many acids, neutralizing the
acid

13. References
(n.d.). Retrieved June 21, 2015, from https://en.wikipedia.org/?title=Marble
(n.d.). Retrieved June 19, 2015, from https://en.wikipedia.org/wiki/Jeffrey_pine
(n.d.). Retrieved June 20, 2015, from https://en.wikipedia.org/wiki/Steller's_jay
(n.d.). Retrieved June 20, 2015, from https://en.wikipedia.org/?title=Coyote
(n.d.). Retrieved June 21, 2015, from https://en.wikipedia.org/?title=Pumice
(n.d.). Retrieved June 21, 2015, from https://en.wikipedia.org/wiki/Magnetite
(n.d.). Retrieved June 21, 2015, from https://en.wikipedia.org/?title=Gneiss
About Jeffrey Pines. (n.d.). Retrieved June 19, 2015, from https://www.giant-sequoia.com/about-sequoia-trees/about-
jeffrey-pines/
Basalt. (n.d.). Retrieved June 21, 2015, from http://www.sandatlas.org/basalt/

14. References Cont.
Coyotes. (n.d.). Retrieved June 20, 2015, from http://www.allthingstahoe.com/coyotye1.html
Coyotes, Coyote Pictures, Coyote Facts - National Geographic. (n.d.). Retrieved June 20, 2015, from
http://animals.nationalgeographic.com/animals/mammals/coyote/
Facts About Lake Tahoe. (n.d.). Retrieved June 19, 2015, from http://tahoe.usgs.gov/facts.html
Geography & History Overview. (n.d.). Retrieved June 19, 2015, from http://tahoe.usgs.gov/geography.html
Gneiss - Metamorphic rocks. (n.d.). Retrieved June 21, 2015, from http://www.sandatlas.org/gneiss/
LAKE TAHOE INFO and FACTS: Lake Tahoe Basin Geology. (n.d.). Retrieved June 19, 2015, from
http://www.tahoecam.com/tahoefacts.html
Lake Tahoe Basin Mgt Unit - Learning Center. (n.d.). Retrieved June 19, 2015, from
http://www.fs.usda.gov/detail/ltbmu/learning/?cid=stelprdb5109570
Marble. (n.d.). Retrieved June 21, 2015, from http://geology.com/rocks/marble.shtml

15. References Cont.
Pumice. (n.d.). Retrieved June 21, 2015, from https://www.mineralseducationcoalition.org/minerals/pumice
Steller's Jay. (n.d.). Retrieved June 20, 2015, from http://www.allaboutbirds.org/guide/Stellers_Jay/id
Steller's Jay. (n.d.). Retrieved June 20, 2015, from http://birdweb.org/Birdweb/bird/stellers_jay
Steller's Jay. (2014, November 13). Retrieved June 20, 2015, from http://www.audubon.org/field-guide/bird/stellers-jay
Trees of Lake Tahoe - The Pines. (2009, March 28). Retrieved June 19, 2015, from
https://beetlesinthebush.wordpress.com/2009/03/28/trees-of-lake-tahoe-the-pines/