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El Portal California

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Journal Article
Published: 21 February 2022
Environmental & Engineering Geoscience (2022) 28 (1): 133–145.
...Jerome V. De Graff; Dennis M. Staley; Greg M. Stock; Kellen Takenaka; Alan L. Gallegos; Chad K. Neptune ABSTRACT Wildfires frequently affect the steep hillslopes near El Portal, California (United States), a small community established during the California Gold Rush in the mid-1800s. In addition...
Journal Article
Published: 01 October 1931
American Mineralogist (1931) 16 (10): 461–468.
...A. A. Fitch Abstract The deposits to be described comprise a group of north-south veins outcropping on both sides of the Merced River (though more abundant to the south), near El Portal, the entrance to Yosemite National Park on the All-Year Highway. They have been traced for a mile to the north...
Journal Article
Journal: GSA Bulletin
Published: 19 October 2022
GSA Bulletin (2023) 135 (5-6): 1547–1565.
... for contentious debates about the Cenozoic tectonic and geomorphologic history of the Sierra Nevada in California. Here we use thermochronometric analysis of radiogenic helium in apatite crystals, coupled with numerical models of crustal temperatures beneath evolving topography, to demonstrate significant late...
FIGURES
First thumbnail for: Late Cenozoic deepening of Yosemite Valley, USA
Second thumbnail for: Late Cenozoic deepening of Yosemite Valley, USA
Third thumbnail for: Late Cenozoic deepening of Yosemite Valley, USA
Journal Article
Journal: Geology
Published: 26 February 2019
Geology (2019) 47 (4): 347–350.
... to the bedrock. Here, we report the composition and formation age of the amorphous coatings in Yosemite National Park, California, USA. The coatings are depleted in base cations (50%–90%) and enriched in silica (10%–50%) as well as trace Fe and U (4- to 100-fold) relative to the bedrock, reflecting dissolution...
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First thumbnail for: Composition and formation age of amorphous silica ...
Second thumbnail for: Composition and formation age of amorphous silica ...
Third thumbnail for: Composition and formation age of amorphous silica ...
Journal Article
Journal: Geosphere
Published: 01 April 2011
Geosphere (2011) 7 (2): 573–581.
... rock avalanche 3600 years B.P. from El Capitan, Yosemite Valley, California : Earth Surface Processes and Landforms , v. 35 , p. 941 – 951 , doi: 10.1002/esp.1982 . Sturznegger M. Stead D. , 2009 , Close-range terrestrial digital photogrammetry and terrestrial laser scanning...
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First thumbnail for: High-resolution three-dimensional imaging and anal...
Second thumbnail for: High-resolution three-dimensional imaging and anal...
Third thumbnail for: High-resolution three-dimensional imaging and anal...
Journal Article
Journal: Geology
Published: 23 August 2017
Geology (2017) 45 (11): 987–990.
... is significant both because it potentially holds information about subglacial conditions and processes, and because it forms a resistant surface that protects landscapes against postglacial weathering. Figure 1. A: Glacial polish example at Pothole Dome, Yosemite National Park, California, USA. Rock...
FIGURES
First thumbnail for: The coating layer of glacial polish
Second thumbnail for: The coating layer of glacial polish
Third thumbnail for: The coating layer of glacial polish
Series: GSA Field Guide
Published: 01 January 2013
DOI: 10.1130/2013.0032(02)
EISBN: 9780813756325
... as far west down the Merced River Canyon as the town of El Portal. If correct, glacial deposits from this event (or events) should be present along the rim of the valley. This stop investigates recent mapping and dating results confirming a glacial origin for sediments exposed at Turtleback Dome...
Journal Article
Journal: Lithosphere
Publisher: GSW
Published: 01 February 2009
Lithosphere (2009) 1 (1): 34–40.
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First thumbnail for: Spatial and temporal variations in denudation of t...
Second thumbnail for: Spatial and temporal variations in denudation of t...
Third thumbnail for: Spatial and temporal variations in denudation of t...
Journal Article
Published: 01 May 2022
Earthquake Spectra (2022) 38 (2): 799–840.
... Stewart, University of California, Los Angeles, 4731 Boelter Hall, Los Angeles, CA 90095, USA. Email: [email protected] As described in the “Introduction” section, NGA-Sub sources are organized in seven major regions that are illustrated in Figure 1 : CAS, ALK, JPN, TWN, NZL, SAM, and CAM...
FIGURES
First thumbnail for: NGA-Sub source and path database
Second thumbnail for: NGA-Sub source and path database
Third thumbnail for: NGA-Sub source and path database
Journal Article
Journal: GSA Bulletin
Published: 01 March 2012
GSA Bulletin (2012) 124 (3-4): 626–640.
... of up to ca. 1.5 Ma in the New River, Virginia, and ca. 3.2 Ma in the Green River, Kentucky. Stock et al. (2004 , 2005) dated buried sediments in caves along rivers in the Sierra Nevada, California, and determined ages that ranged between 0.3 and ≥4.7 Ma. Granger and Smith (2000) , Wolkowinsky...
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First thumbnail for: Dating of Pliocene Colorado River sediments: Impli...
Second thumbnail for: Dating of Pliocene Colorado River sediments: Impli...
Third thumbnail for: Dating of Pliocene Colorado River sediments: Impli...
Journal Article
Published: 24 November 2021
Environmental & Engineering Geoscience (2021) 27 (4): 395–407.
...Christopher J. Pluhar; Kiersti R. Ford; Greg M. Stock; John O. Stone; Susan R. Zimmerman ABSTRACT Yosemite National Park, California, is one of the best-documented sites of historical rockfalls and other rock slope failures; however, past work shows that this record does not capture the infrequent...
Journal Article
Published: 01 May 2015
Environmental & Engineering Geoscience (2015) 21 (2): 111–127.
... from El Capitan, Yosemite Valley, California : Earth Surface Processes Landforms , Vol. 35 , pp. 941 – 951 . Toshioka T. Tsuchidaa T. Sasahara K...
FIGURES
First thumbnail for: Near-Surface Geophysical Imaging of a Talus Deposi...
Second thumbnail for: Near-Surface Geophysical Imaging of a Talus Deposi...
Third thumbnail for: Near-Surface Geophysical Imaging of a Talus Deposi...
Journal Article
Journal: Geosphere
Published: 01 April 2014
Geosphere (2014) 10 (2): 243–263.
...Stephen J. Martel; Greg M. Stock; Garrett Ito Abstract The magnitude of late Cenozoic rock uplift of the Sierra Nevada (California, USA) remains unresolved despite more than a century of investigation, with estimates ranging from essentially zero to ∼3 km of uplift at the range crest. Two sets...
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First thumbnail for: Mechanics of relative and absolute displacements a...
Second thumbnail for: Mechanics of relative and absolute displacements a...
Third thumbnail for: Mechanics of relative and absolute displacements a...
Journal Article
Journal: Geology
Published: 01 May 2010
Geology (2010) 38 (5): 423–426.
... and measurements of bedrock fracture spacing to explore the relationship between erosion rates and rock fracturing at 23 sites along Tuolumne River valley and five sites in Tenaya Canyon in Yosemite National Park, California, USA. Most sites yield 10 Be concentrations that can be best explained as reflecting...
FIGURES
First thumbnail for: Bedrock fracture control of glacial erosion proces...
Second thumbnail for: Bedrock fracture control of glacial erosion proces...
Third thumbnail for: Bedrock fracture control of glacial erosion proces...
Journal Article
Journal: GSA Bulletin
Published: 01 August 1964
GSA Bulletin (1964) 75 (8): 753–758.
... the Devils Postpile, believed by Matthes (1960) to have been extruded between his El Portal (Sherwin?) and Wisconsin glaciations, gives a date of 940,000 ± 160,000 years. U.S. GEOLOGICAL SURVEY, MENLO PARK, CALIF. PUBLICATION AUTHORIZED BY THE DIRECTOR, U.S. GEOLOGICAL SURVEY 27 1 1964...
Journal Article
Journal: AAPG Bulletin
Published: 01 October 1957
AAPG Bulletin (1957) 41 (10): 2243–2256.
... at the University of California, Berkeley, in June, 1956. Manuscript received, January 25, 1957. 2 Department of Geology, Colorado School of Mines, Golden, Colorado. 3 Departments of Geology and Paleontology, University of California, Berkeley, California. Field mapping, stratigraphy...
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First thumbnail for: Upper Devonian Swisshelm Formation of Southeastern...
Second thumbnail for: Upper Devonian Swisshelm Formation of Southeastern...
Third thumbnail for: Upper Devonian Swisshelm Formation of Southeastern...
Journal Article
Journal: AAPG Bulletin
Published: 01 March 1944
AAPG Bulletin (1944) 28 (3): 301–325.
... of it the northern Sonoran portal was open connecting the Mexican geosynclinal sea with the Gulf of California. At the west lay the Gulf of California and the Pacific Ocean. To the southeast it was cut off by waters which filled the Balsas portal. The Coahuila Peninsula was first submerged in upper Aptian time...
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First thumbnail for: Geologic History of Northern Mexico and Its Bearin...
Second thumbnail for: Geologic History of Northern Mexico and Its Bearin...
Third thumbnail for: Geologic History of Northern Mexico and Its Bearin...
Journal Article
Journal: AAPG Bulletin
Published: 01 March 1957
AAPG Bulletin (1957) 41 (3): 466–510.
... unconformably overlies the basement rocks. It is arkosic to quartzose and ranges from 320 to 600 feet in thickness. The El Paso formation (Upper Cambrian-Lower Ordovician) conformably overlies the Bolsa and ranges in thickness from 340 to 715 feet. It consists of dolomite and limestone. The overlying Portal...
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First thumbnail for: Stratigraphic Relations in Chiricahua and Dos Cabe...
Second thumbnail for: Stratigraphic Relations in Chiricahua and Dos Cabe...
Third thumbnail for: Stratigraphic Relations in Chiricahua and Dos Cabe...
Journal Article
Journal: Geosphere
Published: 01 August 2015
Geosphere (2015) 11 (4): 1133–1157.
... the town of El Portal, ∼6 km west of the edge of this map). The southeast face of El Capitan has continuous and steep exposure, fully visible from the valley floor, which is crossed by over 70 named climbing routes and is thus more accessible for observation, mapping, and sampling than other km-tall...
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First thumbnail for: Plutonism in three dimensions: Field and geochemic...
Second thumbnail for: Plutonism in three dimensions: Field and geochemic...
Third thumbnail for: Plutonism in three dimensions: Field and geochemic...
Journal Article
Published: 24 November 2021
Environmental & Engineering Geoscience (2021) 27 (4): 439–453.
... ), composed of portions of the Ferguson Fire and Briceburg Fire burned areas, is located on the western flank of the central Sierra Nevada just west of Yosemite National Park, CA, in the El Portal 15-minute quadrangle. The burned areas are bounded primarily by Bear Creek to the west, California State Route 41...