Publications
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Real-time landslide warning during heavy rainfall
A real-time system for issuing warnings of landslides during major storms is being developed for the San Francisco Bay region, California. The system is based on empirical and theoretical relations between rainfall and landslide initiation, geologic determination of areas susceptible to landslides, real-time monitoring of a regional network of telemetering rain gages, and National Weather Service
Authors
D. K. Keefer, R. C. Wilson, R. K. Mark, E. E. Brabb, W. M. Brown, S. D. Ellen, E. L. Harp, G. F. Wieczorek, C.S. Alger, R.S. Zatkin
Possible Late Middle Ordovician organic carbon isotope excursion: Evidence from Ordovician oils and hydrocarbon source rocks, mid-continent and east-central United States
Oils generated by Middle Ordovician rocks are found throughout the Mid-Continent and east-central regions of the United States. Gas chromatographic characteristics of these oils include a relatively high abundance of n-alkanes with carbon numbers less than 20, a strong predominance of odd-numbered n-alkanes between C10 and C20, and relatively small amounts of branched and cyclic alkanes. Saturated
Authors
Joseph R. Hatch, Stephen R. Jacobson, Brian J. Witzke, J. Bruno Risatti, Donald E. Anders, W. Lynn Watney, K. David Newell, April K. Vuletich
Pressure sensitivity of low permeability sandstones
Detailed core analysis has been carried out on 32 tight sandstones with permeabilities ranging over four orders of magnitude (0.0002 to 4.8 mD at 5000 psi confining pressure). Relationships between gas permeability and net confining pressure were measured for cycles of loading and unloading. For some samples, permeabilities were measured both along and across bedding planes. Large variations in st
Authors
N.H. Kilmer, N.R. Morrow, Janet K. Pitman
Abstracts of papers presented at the Geographic information systems symposium, June 2-4, 1987, Reston, Virginia
No abstract available.
Authors
Marine and nonmarine gas-bearing rocks in Upper Cretaceous Blackhawk and Neslen Formations, eastern Uinta Basin, Utah: Sedimentology, diagenesis, and source rock potential
The Upper Cretaceous Blackhawk and Neslen Formations in the eastern Uinta basin contain large amounts of thermogenic gas that was generated from interbedded humic-rich source rocks. The geometry and distribution of hydrocarbon source and reservoir rocks are controlled by depositional environment. The Blackhawk, composed of laterally extensive sandstone and locally interbedded carbonaceous siltston
Authors
Janet K. Pitman, Karen J. Franczyk, Donald E. Anders
New evidence on the state of stress of the San Andreas fault system
Contemporary in situ tectonic stress indicators along the San Andreas fault system in central California show northeast-directed horizontal compression that is nearly perpendicular to the strike of the fault. Such compression explains recent uplift of the Coast Ranges and the numerous active reverse faults and folds that trend nearly parallel to the San Andreas and that are otherwise unexplainable
Authors
M.D. Zoback, M.L. Zoback, S. Van Mount, J. Suppe, J. P. Eaton, J. H. Healy, D. Oppenheimer, P. Reasenberg, L. Jones, C.B. Raleigh, I.G. Wong, O. Scotti, C. Wentworth
Rock-water interaction in ash-flow tuffs (Yucca Mountain, Nevada, USA)- The record from uranium studies
Forty-eight core samples of ash-flow tuffs from Yucca Mountain, NV, were selected for comparative analysis by uranium-based methods to estimate past interaction with oxidizing water. Results aid in the selection of hydrologically isolated host rocks for radioactive waste disposal. U abundances were consistently more variable than thorium in whole rocks, suggesting some selective redistribution of
Authors
Robert A. Zielinski, Charles A. Bush, R.W. Spengler, B. J. Szabo
Blueschist metamorphism of the Eastern Franciscan belt, northern California
Rocks of the Eastern Franciscan belt, northern California, are divided into two tectonostratigraphic terranes metamorphosed to the blueschist facies, both with a distinct lithologic association and deformational history. The easternmost terrane, the Pickett Peak terrane of Early Cretaceous isotopic age, consists of crenulated mica schist and gneissic to schistose metagraywacke, with lesser alkalic
Authors
A. S. Jayko, M. C. Blake, R.N. Brothers
Significance of Klamath rocks between the Franciscan Complex and Coast Range ophiolite, northern California
Small fault‐bounded slabs of low‐grade (prehnite‐pumpellyite‐bearing) slate, metagraywacke, and greenstone occur between the Coast Range ophiolite and South Fork Mountain Schist for at least 60 km south of the Klamath Mountains, northern California. The metagraywacke slabs differ from typical Franciscan Complex metagraywacke to the west by the absence of blueschist‐facies minerals and the abundanc
Authors
A. S. Jayko, M. C. Blake, Jr., R.N. Brothers
Tectonic evolution of Northwest California and Southwest Oregon
Tectonostratigraphic terrances in northwest California and southwest Oregon record a complex history of subduction, collision, and transform faulting. During the late Jurassic Nevadan orogeny, the Elder Creek-Snow Camp and western Klamath terranes were imbricated during collision of an island-arc system with the continental margin. Subsequent collisions are recorded in the Pickett Peak (Early Cret
Authors
M. Clark Blake, Angela S. Jayko
The non-transferability of a Cretaceous coal model in the San Juan Basin of New Mexico and Colorado
The San Juan Basin of northwest New Mexico and southwest Colorado contains several Upper Cretaceous coal-bearing formations. The coals in these formations were deposited in environments associated with repeated transgressions and regressions of the Western Interior seaway in Late Cretaceous time. A detailed subsurface and surface study of the coal beds in one of these units, the Fruitland Formatio
Authors
James E. Fassett
Paleomagnetism of Middle Tertiary volcanic rocks from the Western Cascade Series, northern California
The Western Cascade Series (WCS) is a 3.5‐km‐thick, crudely homoclinal (east dipping) calcalkaline volcanic sequence of mid‐Oligocene to early Miocene age that crops out near the southern tip of the Cascade Range in northern California. The mean direction of remanent magnetization in the WCS is D, 4.9°; I, 57.6° (N, 53; k, 14.4; α95, 5.3°). When compared to a reference direction for the North Amer
Authors
Myrl E. Beck, Russell F. Burmester, Douglas E. Craig, C. Sherman Grommé, Ray E. Wells