Mountain Range By Elena Kurbatova South Lake in the Sierra Nevada Mountains courtesy of Duane Shoffner Geological History Late Jurassic Cretaceous and Tertiary Periods Kula and ID: 135475
Download Presentation The PPT/PDF document "Geology of the Sierra Nevada" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Slide1
Geology of the Sierra Nevada Mountain Range
By Elena Kurbatova
South Lake in the Sierra Nevada Mountains, courtesy of Duane
Shoffner
Slide2
Geological History Late Jurassic, Cretaceous, and Tertiary Periods
Kula and Farallon plates are subducted under the North American plate.
Hot felsic magma coming from the mantle starts rising, producing a chain of volcanoes on the
continent.
Volcanic eruptions produce layers of solidified magma, most of which stays deep below the surface and forms
plutons
of solid granite.Slide3
Subduction of the Farallon Plate beneath the North American continental margin, 140-100 million years ago.Slide4
Late Cretaceous PeriodPlutons come together to form the single, massive
batholith (deeply imbedded rock).Batholith begins to rise. The
layer of marine sedimentary rock that lay over the mountain is gradually eroded away and deposited in the valley.The granitic core of the range is exposed.Slide5
Granite is exposed Slide6
Tertiary Period
The continental crust east of the Sierra Nevada begins to stretch in an east-west direction. The crust breaks into a series of north-south-trending valleys and mountain ranges—the beginning of the Basin and Range province.
The Sierra Nevada Range starts rising along its eastern margin.Slide7
What might have caused the uplift:The oceanic plates are
subducted and become completely overridden.The North American and Pacific plates come into direct contact for the first time.Shear replaces compression as the North American plate begins interacting with the Pacific plate.On the other side of the Sierra Nevada Range Basin and Range Province is being pulled apart.Slide8
FaultingSlide9
The Sierra Nevada FaultsThe Sierra Nevada Fault is a normal fault produced by tension
There is also a smaller strike-slip fault produced by shearing stressSlide10
The Sierra Nevada is an enormous tilted fault
blockSlide11
Quaternary PeriodNot long after the Sierra uplift begins,
the Earth cools.Glaciers grow in the Sierra highlands and make their way down former stream channels, carving U-shaped valleys. The combination of river and glacier erosion exposes the granitic plutons
previously buried, leaving only a remnant of metamorphic rock on top of some of the Sierra peaks.Slide12
What makes the Sierra Nevada Range geologically interestingGold deposits in the foothill metamorphic belt
A possibility of a major earthquake along the fault lineThe unpredictability of the future plate movementSlide13
Web sites consultedSierra Nevada Physical Geography Joel
Michaelsen http://www.geog.ucsb.edu/~joel/g148_f09/readings/sierra_nevada/sierra_nevada.htmlSierra Nevada Mountains (Geology) http://www.knowledgerush.com/kr/encyclopedia/Sierra_Nevada_Mountains/America's Volcanic Past Sierra Nevadas http://vulcan.wr.usgs.gov/LivingWith/VolcanicPast/Places/volcanic_past_sierra_nevadas.html
Pacific Mountain System http://www.nature.nps.gov/Geology/usgsnps/province/pacifmt.htmlGEOLOGY OF THE SIERRA NEVADAS
Mary Ann
Resendes
http://www.sierrahistorical.org/archives/geology.html
Geology of Yosemite
http://www.nps.gov/yose/naturescience/geology.htm
California Geological History snobear.colorado.edu
/.../
CaliforniaMtns
/
California_geologic_history.pp