Wendy Millan

Geo – 103

Prof. Mark Lawler

June 18, 2015

Lake Tahoe SurroundingsGeology Field Project

The geological changes that occur throughout time has not yet surpassed its recognition, continual evidence of these changes are closer then we expect and can easily be recognized just by looking at our surroundings. My exploration simply took place in my backyard and neighborhood, here, in South Lake Tahoe.

Introduction

Lake Tahoe Basin was formed 3 to 5 million years ago from parallel fractures in the Earths crust as the mountains on both sides rose creating a valley with a shallow lake.

The lake then took shape from faulting of the Earth's crust, volcanic activity and glaciation.

Lava flows that started on the north shore formed barriers or dams, this allowed rivers and streams to flow into the basin slowly filling it to several hundred feet higher than the present stage.

Lake Tahoe was discovered in 1844 by John C. Fremont

(Scott, 1957, Shaffer, 1996)

Geologic history: Lake Tahoe – Past

Lake Tahoe – Present

Lake Tahoe measures about 22 miles long from North to South and about 12 miles wide.

It is located along the border of California and Nevada. The Mountain peaks in Lake Tahoe can rise to more than

10, 000 ft above sea level and with an elevation averaging to

about 6,225 ft. Lake Tahoe is known as the second deepest lakes in

the United States and tenth deepest in the whole world. Containing a maximum depth at 1,645 ft and

averaging in depth of 1,000 ft.

(Scott, 1957, Shaffer, 1996)

The steller’s jay is also known as the long-crested jay,

mountain jay, and pine jay.

The Steller’s jay is native to western North America. Though are known to reside anywhere from coastal

southern Alaska, British Columbia , Pacific Coast,

Rocky Mountains, Mexico and central America.

Fun Fact: Though the Steller’s jay are known for

their bright blue feathers, the appearance is

actually an illusion, the blue pigments actually

are not there, the blue color that is seen is actually

caused by the way the structure of the internal feathers

reflect the light, which then the light reflected tends

to be blue, appearing as blue feathers.

(“Steller's Jay”, 2015, “Steller's Jay” wiki, 2015)

Steller’s Jay (cyanocitta stelleri)

Bird Evolution is thought to of started in the Jurassic period. Fosslilized records of early birds were discovered from Mesozoic – aged rocks found worldwide.

This proves birds evolved from a dinosaur group called maniraptoran theropods.

The specimen of Archaeopteryx, is known as the first known bird, it contained both bird and reptile like features.

(“Steller's Jay”, 2015, “Steller's Jay” wiki, 2015,Vergano, 2014)

Evolution of Steller’s jay

Birds after the Archaeopteryx continued to evolve, changing features with smaller and fused bones to improve flight, feathers more pronounced improving stability and maneuverability, and eventually mainly changing the locomotion from walking to flying .

Ancestors of living birds lived through the late Creataceous period around 65 million years ago. The ancestral lineage still lives throughout the major bird groups presently living.

The Steller’s jay were first discovered in 1741, in 1788 it was officially a new specie and named after Georg Steller, the Steller’s jay.

(“Steller's Jay”, 2015, “Steller's Jay” wiki, 2015,Vergano, 2014)

Epidexipteryx is the first example in the fossil record of a dinosaur flaunting feathers for display.

Retrieved By: ROBERT CLARK, NATIONAL GEOGRAPHIC CREATIVE

Evolution of Steller’s jay

Snow plant is an herbaceous perennial wildflower that

only grows in California, Nevada, and Oregon. Snow plant is easily recognizable for its vibrant

red color. Snow plant is known as a saprophytic, which obtains

nutrients through decaying organic matter. Also known as mycotrophic which also

obtains nutrients from fungi. They often grow in cluster in areas in humus of

coniferous Forests. Because this plant is a rare beauty, it is one of the

first plants in California to be protected by law,

picking or damaging this plant holds a heavy fine.

(Blackwell, 1997, Graf, 1999)

 

Snow Plant

Plantae –> Tracheobionta –> Spermatophyta –> Magnoliophyta – >Magnoliopsida –> Dilleniidae –> Ericales –> Monotropaceae –> Sarcodes Torr –> Sarcodes Sanguinea Torr.

The first land plants, including mosses, emerged during the Ordovician period.

Algae was known as the first type of plant that arose over a billion years ago.

Plants in the kingdom Plantae, did not emerge until roughly 700 million years ago.

It was in the Devonian period about 416-360 million years ago that plants grew massively in height creating the large ferns we see today.

Finally it was in the Cretaceous period when the first flowering plants (angiosperms) evolved, these flowering plants created pollen, which were carried by insects then spread throughout creating more plants.

The latest variety of plants, the grasses, evolved from the angiosperms about 35 million years ago.

(Blackwell, 1997, Graf, 1999)

Snow Plant (Sarcodes sanguinea)

  Aspen roots interconnect, it’s the roots that sprout out, rather than the

seeds. Making them the largest living organism in the world.  The Quaking Aspen is widely distributed through

North America, Canada and central Mexico.  The Quaking Aspens are also known for the

quaking or raddling sounds the leaves make

when the wind blows, almost sounds musical. One unique feature is under their white outer bark

lies a thin photosynthetic green layer which

provides the tree to synthesize sugars, which allows

continual growth through the winter. Quaking aspen can individually grow stems

that can live to about 50 to 60 years, and even up

to 150 in the West.

(Graff, 1999, Blackwell, 2007)

Quaking Aspen

Plantae -> Angiosperms -> Eudicots -> Rosids -> Malpighiales -> Salicaceae -> Populus -> Populus -> P.tremuloides

The  first vascular plant evolved around 400 million years ago, during the Silurian geologic period.  It was during the Devonian period that the first real tree emerged. By the Carboniferous period about 360 millionyears ago, trees finally were recognizable and made a significant element in plant life.  Trees that existed during the Devonian and Carboniferous periods, tree ferns from that era can still be found living in areas of the Australian tropical rainforests.

(Graff, 1999, Blackwell, 2007)

Quaking Aspen (Populus tremuloides)

Observing the rock it appears to be white almost clear crystal in color.

Found in small sizes less then 2 inches long or wide. It is a non foliated metamorphic rock. It’s produced from metamorphism of limestone. It composes of primarily calcium carbonate.

(“Rock Types, 2015, “Igneous Metamorphic Sedimentary Rock Gallery,” 2006)

Rock Sample 1: Metamorphic - Marble

I believe this rock is metamorphic, it closely resembles a sedimentary rock in my next example, which made this a little tough to identify.

This rock was not large nor small in size, it contained sharp edges as though it broke off in some areas.

This is a foliated metamorphic rock. It is formed through the metamorphism of shale. This low grade metamorphic rock can easily split into thin pieces.

(“Rock Types, 2015, “Igneous Metamorphic Sedimentary Rock Gallery,” 2006)

Rock Sample 2: Metamorphic - Slate

I Believe this is a sedimentary rock, it contains sharp edges with a distinct dark gray color, again not completely sure this shale, look a lot like slate, was hard identifying.

Can be seen in larger rocks or small broken of pieces. Typically breaks to thin flat pieces. Similar to that found in slate, which made

it little harder to identify. This sedimentary rock is made up of clay-size weathering debris. Shale is a clastic sedimentary rock.

(“Rock Types, 2015, “Igneous Metamorphic Sedimentary Rock Gallery,” 2006)

Rock Sample 3: Sedimentary - Shale

Honestly wasn’t sure on this one, looks like it would be in the sedimentary family of sandstone. ( In picture the largest rock)

This rock I found average size, though hard to recognized, I believe it’s a sedimentary rock.

Some of the colors stand out with a pale orange type color and containing many odd structures along the rock.

This sedimentary rock is made up mainly of sand-size weathering debris This rock can be found in many areas from beaches to deserts.

(“Rock Types, 2015, “Igneous Metamorphic Sedimentary Rock Gallery,” 2006)

Rock Sample 4: Sedimentary -Sandstone

I believe this rock is igneous, though similar to other rock types. The dark crystalized specs made me believe this was igneous.

This rock was not big in size about 3 inches length and width, it contains mix of colors of white, crystal, and black stones.

This is a coarse-grained intrusive igneous rock It contains a mixture of feldspar, pyroxene, hornblende, and sometimes

quartz.

(“Rock Types, 2015, “Igneous Metamorphic Sedimentary Rock Gallery,” 2006)

Rock Sample 5: Igneous - Diorite

Blackwell, L. R. (1997). Wildflowers of the Tahoe Sierra: From forest deep to mountain peak. Redmond, WA: Lone Pine Pub.

Blackwell, L. R. (2007). Tahoe wildflowers ; a month-by-month guide to wildflowers in the Tahoe Basin and surrounding areas. Guilford, Conn: Falcon Guide.

Graf, M. (1999). Plants of the Tahoe basin: Flowering plants, trees, and ferns : a photographic guide. Sacramento, Calif: California Native Plant Society Press.

Schaffer, J. P. (1996). Desolation Wilderness and the South Lake Tahoe Basin. Berkeley, CA: Wilderness Press.

Scott, E. B. (1957). The saga of Lake Tahoe. Crystal Bay, Lake Tahoe, Nevada: Sierra-Tahoe Pub. Co.

References

Gauna, J. Forest. Plant of the week. Retrieved from: http://www.fs.fed.us/wildflowers/beauty/mycotrophic/sarcodes_sanguinea.shtml

Geography and History Overview .(n.d.).Retrieved from: http://tahoe.usgs.gov/geography.html

Nix, Steve. Evolution of Forest and trees. Understanding how the Earths first Forests developed. Retrieved from:http://forestry.about.com/od/ancientforests/a/Evolution-Of-Forests-And-Trees.htm

Populus tremuloides. (2015, March 25). In Wikipedia, The Free Encyclopedia. Retrieved, June 16, 2015, from https://en.wikipedia.org/w/index.php?title=Populus_tremuloides&oldid=653531440

Steller's jay. (2015, April 20). In Wikipedia, The Free Encyclopedia. Retrieved 20:02, June 16, 2015, fromhttps://en.wikipedia.org/w/index.php?title=Steller%27s_jay&oldid=657359302

“Steller's Jay”. [Online]. Natural History Notebooks. Canadian Museum of Nature. Last updated 2015-04-28. (Web site consulted 2015-06-16). http://nature.ca/notebooks/english/stellersjay.htm

Vergano, Dan. (2014, September 25). Birds evolved from Dinosaurs slowly – Then took off. Retrieved from: http://news.nationalgeographic.com/news/2014/09/140925-bird-dinosaur-evolution-burst-science/

Online References