February Geology and GSA Today media highlights

Dynamic adjustments in channel width in response to a forced diversion: Gower Gulch, Death Valley National Park, California
Noah Snyder and Lisa Kammer, Department of Geology and Geophysics, Boston College, 140 Commonwealth Avenue, Chestnut Hill, Massachusetts 02130, USA. Pages 187-190.

Snyder and Kammer's study makes use of an unusual experiment to make new observations about stream erosion processes. In 1941, Furnace Creek, the main desert river on the east side of Death Valley, California, was diverted into a small canyon (Gower Gulch) in an effort to alleviate flooding in the village downstream. This study analyzes aerial photographs from 1948 to 1995, and 2005 field and airborne laser elevation surveys. These images show that Gower Gulch is undergoing a variable, dynamic response to the diversion, with some areas incising and narrowing, and others widening. These findings have important implications to studies that seek to understand stream responses to changes in climate or tectonics.

GSA TODAY Science Article

Are we now living in the Anthropocene?
Jan Zalasiewicz et al., Department of Geology, University of Leicester, Leicester LE1 7RH, UK

"In 2002," write Zalasiewicz and colleagues in this revolutionary proposal, "Paul Crutzen, the Nobel Prize-winning chemist, suggested that we had left the Holocene and had entered a new epoch - the Anthropocene - because of the global environmental effects of increased human population and economic development." The authors document a radical yet compelling case for the idea that the appearance of humans has so physically changed Earth that there is no organic justification for linking pre- and post-industrialized Earth within the same epoch (the Holocene). With this article, Zalasiewicz and colleagues have laid the scholarly groundwork for the formal adoption by the International Commission on Stratigraphy of the Anthropocene as the youngest epoch of, and most recent addition to, the geological timescale.

To review the abstracts for these articles, go to www.gsajournals.org. View the complete table of contents for the current issue of GEOLOGY at www.gsajournals.org/gsaonline/?request=get-current-toc&issn=0091-7613.

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