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Preliminary carbonate lithofacies maps and possible dolomite porosity trends, Mississippian-Pennsylvanian Lisburne Group, North Slope, Alaska

Carbonate porosity within the Mississippian-Pennsylvanian age Lisburne Group is probably extensively developed in the subsurface of the North Slope. The Lisburne Group may prove to be one of the more significant reservoir zones in the region and should not be overlooked in any exploration program. Isopach maps for the total Lisburne Group and other upper Paleozoic and Mesozoic rocks, North Slope,
Authors
Augustus K. Armstrong

Seismic environment of the Burro Flats site, Ventura County, California: a brief, limited literature review

A limited review of available literature suggests that the maximum horizontal ground acceleration at the Burro Flats site from earthquakes in the region could range from less than 0.1 to 0.49 g. A magnitude 8 earthquake on the nearby San Andreas fault could produce ground acceleration in the range 0.18 to 0.31 g, and an expectable larger earthquake on that fault could produce larger accelerations.
Authors
Carl M. Wentworth, Manuel G. Bonilla, Jane M. Buchanan

Blueschist-facies metamorphism related to regional thrust faulting

Rocks of the blueschist (glaucophane schist) facies occur throughout the world in narrow tectonic belts associated with ultramafic rocks. In the Coast Range province of California, blueschist rocks are devloped in the eugeosynclinal Franciscan Formation of Late Mesozoic age. The blueschist rocks form a narrow belt for more than 800 km along the eastern margin of this province and commonly are sepa
Authors
M. C. Blake, W. P. Irwin, R. G. Coleman

Shatter cones at Sierra Madera, Texas

Shatter cones abound in the central uplift of Sierra Madera and they occur as far as 6.5 kilometers from the center. Apical angles average near 90 degrees. Whole cones and full cones represented by diversely oriented cone segments in any structural block show relatively uniform orientations of axes and a dominant direction of point. The cones predate faulting and folding in the central uplift, and
Authors
Keith A. Howard, Terry W. Offield

Isotopic age of the Nevadan Orogeny and older Plutonic and metamorphic events in the Klamath Mountains, California

Several metamorphic and plutonic events have been recognized in the Klamath Mountains utilizing potassium-argon and rubidium-strontium mineral and whole-rock ages. The oldest known metamorphic event in the region produced the Abrams Mica Schist and the co-extensive Salmon Hornblende Schist. Strontium evolution diagrams indicate that the age of primary metamorphism of the Abrams Mica Schist is appr
Authors
Marvin A. Lanphere, William P. Irwin, Preston E. Hotz