Lake Clark fault, assessment of tectonic activity based on reconnaissance mapping of glacial deposits, northwestern Cook Inlet, Alaska (poster): Eos Trans. AGU, Fall Meet. Suppl., Abstract G33B-0658, San Francisco, California, December 16, 2009

2009 ◽  
Author(s):  
R. D. Koehler ◽  
R. D. Reger
Keyword(s):  
San Francisco ◽  
Tectonic Activity ◽  
Cook Inlet ◽  
Glacial Deposits ◽  
Clark Fault

Asbestiform Minerals of the Franciscan Assemblage in California with a Focus on the Calaveras Dam Replacement Project

2020 ◽  
Vol 26 (1) ◽  
pp. 21-28
Author(s):  
R. Mark Bailey
Keyword(s):  
San Francisco ◽  
North American Plate ◽  
Tectonic Activity ◽  
Bay Area ◽  
The North ◽  
Rock Types ◽  
Selected Area Electron Diffraction ◽  
Transmission Electron ◽  
Naturally Occurring Asbestos ◽  
Asbestiform Minerals

ABSTRACT The San Francisco Bay Area is underlain by bedrock of the Franciscan Assemblage, which outcrops in numerous places. A significant portion of these outcrops consists of rock types that contain both regulated and unregulated asbestiform minerals, including ultra-mafic serpentinites, various greenstones, amphibolites, blueschist, and other schists (talc-tremolite, actinolite, etc.). These rocks are a legacy of tectonic activity that occurred on the west coast margin of the North American plate ∼65–150 MY ago during subduction of the East Pacific and Farallon plates. The Calaveras Dam Replacement Project (CDRP), located in Fremont, California, is an example of an area within the Franciscan Assemblage that is substantially underlain by metamorphosed oceanic sedimentary, mafic, and ultra-mafic rocks in a tectonic subduction zone mélange with highly disrupted relationships between adjoining rock bodies with different pressure/temperature metamorphic histories. In order to protect the health of workers and residents in the surrounding area, an extensive effort was taken to identify, categorize, and monitor the types, locations, and concentrations of naturally occurring asbestos at the site. Using a combination of geologic field observations and transmission electron microscopy, energy dispersive X-ray, and selected area electron diffraction analysis of airborne particulate and rock/soil samples, the CDRP was discovered to contain chrysotile-bearing serpentine. It also had as a range of amphibole-containing rocks, including blueschist, amphibolite schist, and eclogite, with at least 19 different regulated and non-regulated fibrous amphibole minerals identified. The extensive solid solution behavior of the amphiboles makes definitive identification difficult, though a scheme was created that allowed asbestos mineral fingerprinting of various areas of the project site.

Regionally Optimized Background Earthquake Rates from ETAS (ROBERE) for Probabilistic Seismic Hazard Assessment

2020 ◽  
Vol 110 (3) ◽  
pp. 1172-1190 ◽  
Author(s):  
Andrea L. Llenos ◽  
Andrew J. Michael
Keyword(s):  
Seismic Hazard ◽  
San Francisco ◽  
Hazard Assessment ◽  
Seismic Hazard Assessment ◽  
B Value ◽  
Tectonic Activity ◽  
Probabilistic Seismic Hazard Assessment ◽  
Probabilistic Seismic Hazard ◽  
Background Rate ◽  
Aftershock Sequences

ABSTRACT We use an epidemic-type aftershock sequence (ETAS) based approach to develop a regionally optimized background earthquake rates from ETAS (ROBERE) method for probabilistic seismic hazard assessment. ROBERE fits parameters to the full seismicity catalog for a region with maximum-likelihood estimation, including uncertainty. It then averages the earthquake rates over a suite of catalogs from which foreshocks and aftershocks have been removed using stochastic declustering while maintaining the same Gaussian smoothing currently used for the U.S. Geological Survey National Seismic Hazard Model (NSHM). The NSHM currently determines these rates by smoothing a single catalog from which foreshocks and aftershocks have been removed using the method of Gardner and Knopoff (1974; hereafter, GK74). The parameters used in GK74 were determined from subjectively identified aftershock sequences, unlike ROBERE, in which both background rate and aftershock triggering parameters are objectively fitted. A major difference between the impacts of the two methods is GK74 significantly reduces the b-value, a critical value for seismic hazard analysis, whereas ROBERE maintains the original b-value from the full catalog. We apply these methods to the induced seismicity in Oklahoma and Kansas and tectonic activity in the San Francisco Bay Region. Using GK74 gives lower overall earthquake rates but estimates higher hazard due to the reduction in the b-value. ROBERE provides higher earthquake rates, at the magnitude of completeness, but lower hazard because it does not alter the b-value. We test two other declustering methods that produce results closer to ROBERE but do not use objectively fit parameters, include uncertainty, and may not work as well in other areas. We suggest adopting ROBERE for the NSHM so that our hazard estimates are based on an objective analysis, including uncertainty, and do not depend strongly on potentially biased b-values, which was never the goal of the existing methodology.

DISTRIBUTION OF VOLATILE HYDROCARBONS IN SOME PACIFIC OCEAN WATERS

1977 ◽  
Vol 1977 (1) ◽  
pp. 589-591 ◽  
Author(s):  
Charles Bruce Koons
Keyword(s):  
San Francisco ◽  
West Coast ◽  
Geographic Location ◽  
Ocean Water ◽  
Total Volatile ◽  
Cook Inlet ◽  
Near Surface ◽  
Volatile Hydrocarbons ◽  
Marine Life ◽  
Surface Samples

ABSTRACT Recent studies conducted by several investigators indicate that the volatile hydrocarbons in the C4to C8 range, including benzene and toluene, are generally more toxic to marine life than the higher molecular weight hydrocarbons. However, very little data have been published on the distribution of these volatile hydrocarbons in the world's oceans. During 1974, ocean water samples were collected from tankers along three routes, including: U. S. west coast (San Francisco) to Cook Inlet, Alaska; U.S. west coast (San Francisco) to Panama; and U.S. west coast (San Francisco) to Singapore. One hundred thirty-eight samples were taken near the surface and at a depth of about 10 meters and were analyzed for total volatile (C4_C8) hydrocarbons. For the near-surface samples, a median concentration of 0.33 ppb (by weight) was found; for the −10 meter samples, a median of 0.10 ppb. Some variations in amounts were observed according to the geographic location of the samples. Sampling and analysis methods are briefly discussed.

Ultrastructural Localization of Antigens by Capillary Action Immunocytochemistry

1996 ◽  
Vol 54 ◽  
pp. 40-41
Author(s):  
László G. Kömüves
Keyword(s):  
San Francisco ◽  
Colloidal Gold ◽  
Specific Binding ◽  
Ultrastructural Localization ◽  
Ultrastructural Level ◽  
Uranyl Acetate ◽  
Adhesive Tape ◽  
Distilled Water ◽  
Capillary Action ◽  
Rabbit Igg

Light microscopic immunohistochemistry based on the principle of capillary action staining is a widely used method to localize antigens. Capillary action immunostaining, however, has not been tested or applied to detect antigens at the ultrastructural level. The aim of this work was to establish a capillary action staining method for localization of intracellular antigens, using colloidal gold probes.Post-embedding capillary action immunocytochemistry was used to detect maternal IgG in the small intestine of newborn suckling piglets. Pieces of the jejunum of newborn piglets suckled for 12 h were fixed and embedded into LR White resin. Sections on nickel grids were secured on a capillary action glass slide (100 μm wide capillary gap, Bio-Tek Solutions, Santa Barbara CA, distributed by CMS, Houston, TX) by double sided adhesive tape. Immunolabeling was performed by applying reagents over the grids using capillary action and removing reagents by blotting on filter paper. Reagents for capillary action staining were from Biomeda (Foster City, CA). The following steps were performed: 1) wet the surface of the sections with automation buffer twice, 5 min each; 2) block non-specific binding sites with tissue conditioner, 10 min; 3) apply first antibody (affinity-purified rabbit anti-porcine IgG, Sigma Chem. Co., St. Louis, MO), diluted in probe diluent, 1 hour; 4) wash with automation buffer three times, 5 min each; 5) apply gold probe (goat anti-rabbit IgG conjugated to 10 nm colloidal gold, Zymed Laboratories, South San Francisco, CA) diluted in probe diluent, 30 min; 6) wash with automation buffer three times, 5 min each; 7) post-fix with 5% glutaraldehyde in PBS for 10 min; 8) wash with PBS twice, 5 min each; 9) contrast with 1% OSO4 in PBS for 15 min; 10) wash with PBS followed by distilled water for5 min each; 11) stain with 2% uranyl acetate for 10 min; 12) stain with lead citrate for 2 min; 13) wash with distilled water three times, 1 min each. The glass slides were separated, and the grids were air-dried, then removed from the adhesive tape. The following controls were used to ensure the specificity of labeling: i) omission of the first antibody; ii) normal rabbit IgG in lieu of first antibody; iii) rabbit anti-porcine IgG absorbed with porcine IgG.

Game Changer

2011 ◽  
Vol 20 (1) ◽  
pp. 17-18 ◽  
Author(s):  
Lateef McLeod
Keyword(s):  
San Francisco ◽  
Mobile Technology ◽  
Technology Tools ◽  
Communication Challenges ◽  
Communication Needs ◽  
Game Changer

Abstract Individuals with significant communication challenges need to communicate across many different venues. The author, from the perspective of an individual who uses AAC, discusses the strengths and weaknesses of both traditional AAC technologies and new mobile AAC technologies. He describes how access to AAC has allowed him to fulfill his dreams as a presenter and writer. He successfully manages a blog in San Francisco, writes grants, and has published his first book of poetry. Not one AAC device fits all of his communication needs; however, access to mobile technology tools has increased his flexibility across environments and given him another successful tool for communication.

126: Nephrectomy for Traumatic Renal Injuries: 26 Year Experience at San Francisco General Hospital

2005 ◽  
Vol 173 (4S) ◽  
pp. 34-34
Author(s):  
Viraj A. Master ◽  
Jennifer Young ◽  
Jack W. McAninch
Keyword(s):  
General Hospital ◽  
San Francisco ◽  
Renal Injuries
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