This Science News Wire page contains a press release issued by an organization and is provided to you "as is" with little or no review from Science X staff.

Geosphere builds momentum with 17 newly published studies and a new series

November 28th, 2012

Geosphere articles posted online 16 November 2012 cover a variety of topics, such as the geophysics of the Hogri fault zone, 5 km offshore of the Diablo Canyon nuclear power plant; using web-based GIS technologies and readily available global remote sensing datasets for investigations of arid land; the structure and evolution of the U.S. Sierra Nevada; the ANDRILL McMurdo Ice Shelf and Southern McMurdo Sound Drilling Projects; and climate-tectonic interactions in the southern Alaskan orogen.

Abstracts for these and other Geosphere papers are available at http://geosphere.gsapubs.org/. Representatives of the media may obtain complimentary copies of Geosphere articles by contacting Kea Giles at the address above.

Please discuss articles of interest with the authors before publishing stories on their work, and please make reference to Geosphere in articles published. Contact Kea Giles for additional information or assistance.

Non-media requests for articles may be directed to GSA Sales and Service, gsaservice@geosociety.org.

Influence of fault trend, bends, and convergence on shallow structure and geomorphology of the Hosgri strike-slip fault, offshore central California

Samuel Y. Johnson and Janet T. Watt, U.S. Geological Survey, 400 Natural Bridges Drive, Santa Cruz, California 95060, USA. Posted online 16 November 2012; http://dx.doi.org/10.1130/GES00830.1.

Comprehensive geophysical data are used to document and map the active, continuous, strike-slip Hosgri fault zone for more than 95 km in offshore central California. Slight bends and changes in fault trend control the development of fault-bounded seafloor uplifts and sedimentary basins. Fault slices develop in complex areas where the Hosgri fault obliquely converges with the Los Osos and Shoreline faults, and the regional uplift at Piedras Blancas formed above diverging Hosgri fault strands. Results presented by Samuel Y. Johnson and Janet T. Watt provide a model that can be applied more broadly for understanding the shallow structure and evolution of strike-slip fault zones, as well as new information to better constrain regional earthquake hazard assessment. Enhanced hazard assessment is especially timely because the Hosgri fault zone lies just 5 km offshore of the Diablo Canyon nuclear power plant.

Eruptive history of Mount Katmai, Alaska

Wes Hildreth and Judy Fierstein, Volcano Science Center, U.S. Geological Survey, MS 910, Menlo Park, California 94025, USA. Posted online 16 November 2012; http://dx.doi.org/10.1130/GES00817.1.

Mount Katmai has long been recognized for its caldera collapse during the great pyroclastic eruption of 1912 (which vented 10 km away at Novarupta in the Valley of Ten Thousand Smokes), but little has previously been reported about the geology of the remote ice-clad stratovolcano itself. Over several seasons, Wes Hildreth and Judy Fierstein reconnoitered all parts of the edifice and sampled most of the lava flows exposed on its flanks and caldera rim. The precipitous inner walls of the 1912 caldera remain too unstable for systematic sampling, so they provide instead a photographic and interpretive record of the wall sequences exposed.

Deposition and deformation in the deepwater sediments of the offshore Barreirinhas Basin, Brazil

Ana Krueger et al., Dept. of Earth and Atmospheric Sciences, University of Houston, Houston, Texas 77204-5007, USA. Posted online 16 November 2012; http://dx.doi.org/10.1130/GES00805.1.

The Barreirinhas Basin is an ideal location to study shale-dominated gravity-driven thrusting systems because of the limited areal extent of the deformed areas compared to other areas in the world. Regional seismic reflection profiles across the Barreirinhas Basin on the Brazilian Equatorial margin show two major deepwater fold and thrust belts linked landward to extensional fault systems. Thrust faults are interpreted to be products of shortening caused by gravity-driven extension on the continental margin that involve rocks of both the shelf and the slope. Results show two main deformation events during the Cretaceous (between 84 and 89 million years ago [89 to 84 Ma]) and several episodes during the Later Cenozoic (ca. 55

Citation: Geosphere builds momentum with 17 newly published studies and a new series (2012, November 28) retrieved 3 August 2026 from https://sciencex.com/wire-news/115578949/geosphere-builds-momentum-with-17-newly-published-studies-and-a.html

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.