Geology of lake TahoeBy:Steven Meza

Lake Tahoe Facts • Lake Tahoe was formed by tectonic movements about 2 million years ago. The Tahoe

basin went under and between the Sierra crest in the west and east of the Carson range.

• Between 155-300 million years ago the north American plate broke off from Pangaea and drifted west towards a with the sierra Nevadas

• Tectonic shifts also created volcanic activity about 4-25 million years ago which cause magma to through the faults which resulted in damming and gaps filling in the valley

• The formation of Fallen leaf lake, Donner lake and Emerald Bay where formed by movement of glaciers about ten thousand years ago during an ice age

• Sources History of Tahoe, Geology of Tahoe and Sierra Nevada

Lake Tahoe Vegetation • Pine trees common to the Tahoe basin include Jeffrey pine, ponderosa and sugar

pines • There is a wide range of vegetation that ranges from plants being up 10 thousand feet

high to 300 feet below the surface of the lake.• In the 1800’s lodging began in the basin and in 1859 60% of trees had been clear cut • The Three most common type of vegetation found in lake Tahoe are shrub association,

subalpine forest, meadow association, and deciduous riparian • Source protecting plant communities in the Lake Tahoe Basin

Green leaf Manzanita

• Green leaf Manzanita scientific name Arctostaphylos patula Kingdom: Plantae and Ericacecae family is part of and generally found in the western mountain range

• Its adaptation of the plant consist of well drained rocky slopes, and is often found near high elevations and forest.

• They can withstand wet winters and dry summers usually 1-2 m tall• Source NRCS plant life

Snow Plant

• Scientific name: Sarcodes sanguinea • Order: Ericales• Family: Ericaceae• Genus: Sarcodes• Species: S. sanguine

• This plant get its life from an underground fungi and doesn’t use photosynthesis • It is often found near pine trees due to its dependency of fungi. It has no chlorophyll

so it must get nutrients from fungi called mycorrhizae • The size ranges from 6-12 inches in height and is tube shaped and blume through

may to july • Source U.S Forest Service

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Lake Tahoe Rocks: Granite Rocks

• It is a type of intrusive, igneous rock, and felsic • Granite rocks form by coiling magma that is trapped under earth’s

surface• It is made up of quartz, feldspar and mica • Much of the earth’s continental crust in contains granite and most of

it came during the Precambrian age • Source: Wikipedia.org/granite

Basalt Rocks • It is an aphanitic igneous rock contains feldspar and quartz and is

one of the most common rocks in the world • Has a fine grain size and often looks blacks or greyish and consist of

olivine and pyroxene • Created when lava flow sheets building in a plateau or is balloon up

that is formed when it comes in contact with water and it will have flossy outside layer or fine grained

• Source: rocks.com, Wikipedia

Northern Goshawk• Kingdom: Animalia• Phylum: Chordata• Class: Aves• Order: Falconiformes• (Family: Accipitridae• Genus: Accipiter• Species: A. gentilis

• Live in the Tahoe basin all year long and prey on other birds and rodents • Has a long tail, short broad wings and can reach speeds up to 38 mph • There breeding habit include nesting through march and April and time for

the eggs to hatch ranges from 28-35 days and the young leave the nest usually after a month

• Source Wikipedia , KeepTahoeBlue.org

Pika • Kingdom: Animalia• Phylum: Chordata• Class: Mammalia• Order: Lagomorpha• Family: Ochotonidae• Genus: Ochotona

• Pika are often found in the basins rocky peaks and prefer the high elevations due to their sensitivity to warm temperatures

• The have adapted to the Tahoe winters buy using stacked up plants for their shelter .• They are herbivores and are diurnal and are very active during the daytime and very

active before winter season.• Source Wikipedia , KeepTahoeBlue.org

Works cited • http://en.wikipedia.org/wiki/Pika • http://en.wikipedia.org/wiki/Northern_Goshawk • http://www.keeptahoeblue.org/abouttahoe/animals-plants • Protecting plant communities in the Lake Tahoe Basin http://

eh2o.saic.com/tiimsWebsite/Content/BasinTopics/vegetation/default.html • http://en.wikipedia.org/wiki/Basalt • History of Tahoe http://

www.gotahoenorth.com/about-tahoe/tahoe-history-and-facts/history-of-tahoe

• Geology of Lake Tahoe and Sierra Nevada http://donsnotes.com/tahoe/geology.html

• NRCS Plant Guide http://www.plant-materials.nrcs.usda.gov/pubs/capmspg5871.pdf

• US forest Service http://www.fs.fed.us/wildflowers/plant-of-the-week/sarcodes_sanguinea.shtml

• Rocks.com http://www.rocks-rock.com/basalt.html