Field study

Field StudyExploring Lake Tahoe

Lake Tahoe GeologyLake Tahoe is located along the California/ Nevada border The Tahoe basin was formed by faulting around 5-10 million years ago. Around 2million years ago, lava from Mt. Pluto formed a barrier across the northeast outlet, Lake Tahoe filled with water from different rivers and streams. During the pleistocene, large glaciers grew in surrounding areas of Lake Tahoe. This caused the forming of U-shaped valleys (Emerald Bay and Fallen Leaf, among others)Lake Tahoe is 22 miles long and 12 miles wide with 72 miles of shorelineLake Tahoe's greatest depth is 1,592 ft.Average elevation is 6225 ft.63 stream flow into the lake, but only the Truckee River (pictured here) flows out .(tahoebest.com.)

American Black Bear

So. Lake Tahoe is home to many different animals, among these animals is the American Black Bear. Bears frequent residential areas and have become accustomed to humans. Frequency of bear sightings has increased since much their natural habitat was destroyed in the Angora fire of 2007.

Black Bear- Scientific name: Ursus Americanus

Fossil records show that bears most likely evolved from canidae. Bears are more closely related to dogs than any other animal.

Kingdom    —    AnimaliaPhylum     —     ChordataClass         —     MammaliaOrder         —     CarnivoraFamily      —      UrsidaeGenus       —     Ursus

Species     —     americanus(americanbear.org)

Greenleaf ManzanitaScientific name— Arctostaphylos Patula E. Greene Description—evergreen shrub, grows to about 3 ft’ tall with oval shaped leaves Group—dicot Family--ericaceaeFound in well drained rocky slopesLikes cool dry summers and wet winters (usda.gov)

Greenleaf Manzanita is thought to be a hybrid from Whiteleaf Manzanita (A. viscida) and Mariposa Manzanita (A. v. ssp. mariposa) pictured above respectively (usda.gov)

I believe this is a Lodgepole pineScientific name—Pinus contorta Douglas ex Louden

Description—Evergreen tree, grows around 13 to 16 ft’Group—gymnosperm76 different species

Kingdom Plantae – Plants Subkingdom Tracheobionta – Vascular plants Superdivision Spermatophyta – Seed plants Division Coniferophyta – Conifers Class Pinopsida Order PinalesFamily Pinaceae – Pine family Genus Pinus L. – pine Species Pinus contorta Douglas ex Louden – lodgepole pine

Igneous rock—crystallized from hot molten rock

I believe this rock to be granite.Composition group—sialic Granite’s texture is coarse and grainy.The light color comes from the light shaped minerals such as quartz and feldspar

(GEL 103 Lecture Notes, 2011)

Metamorphic—rocks changed by heat, pressure or chemical activity

I believe that this rock may be phyllite. Phyllite is mainly made up of fine grained mica, traces of garnet may be present. Phyllite is intermediate in grade. It comes from the metamorphism of shale.

(GEL 103 Lecture Notes, 2011)

References

• Evolution and taxonomy of the black bear. (n.d.). In The American bear association. Retrieved July 18, 2011, from http://www.americanbear.org/Evolution%20-%20Taxonomy.htm

• GEL 103 Lecture Notes, 2011• Graff, M. (1999). Plants of the Tahoe basin; Flowering plants, trees, and ferns (First ed., pp. 72-73). Sacramento, CA: California Native Plant Society Press.

• Plants profile. (n.d.). In United States department of agriculture. Retrieved July 18, 2011, from http://plants.usda.gov/java/profile?symbol=ARCTO3

• The geological history of the Lake Tahoe basin. (n.d.). In Tahoe Cam. Retrieved July 17, 2011, from http://www.tahoecam.com/tahoefacts.html