December GEOLOGY and GSA TODAY media ...(ies have been invoked as a cause for the...)

Date:11/29/2007

ies have been invoked as a cause for the breakup of Rodinia, geological evidence, such as anomalously hot mantle-derived magmas (like picrite or komatiite), for the proposed mantle plume is rare. In this study, Li et al. present geochronological and geochemical data from a suite of pillowed lavas in central South China. Their work demonstrates that these rocks were typical komatiitic basalts generated approximately 825 million years ago by melting of an anomalously hot mantle source similar to that of modern mantle plumes. Thus, these komatiitic basalts provide the first solid petrological evidence for the proposed approximately 825 million-year-old mantle plume that played a key role in the breakup of the supercontinent Rodinia.

---

Postglacial slip-rate increase on the Teton normal fault, northern Basin and Range Province, caused by melting of the Yellowstone ice cap and deglaciation of the Teton Range
Andrea Hampel et al., Ruhr-Universitaet Bochum, Institut fuer Geologie, Mineralogie und Geophysik, Universitaetsstr. 150, Bochum, Nordrhein-Westfalen 44801, Germany. Pages 1107-1110.

The Teton Range in the northeastern Basin-and-Range Province is famous for its high relief, with peaks up to 13,770 ft high (4,197 m), and a spectacular glacial geomorphology with deep U-shaped valleys. The rapid rise of this rugged mountain range in the last few million of years is related to repeated earthquakes on the Teton normal fault, which runs north-south along the mountain front. Today, the Teton fault represents a prominent seismic gap in the greater Yellowstone-Teton region; however, up to 50-m-high fault scarps and paleoseismologic data document that multiple earthquakes ruptured the Teton fault in the last 15,000 years, i.e. after the last glaciation. Hampel et al.s study shows that these earthquakes can be explained as a response to the melting of glaciers in the Teton Range and the large Yellowstone ice cap. More generally, their results im
'/>"/>

Contact: Ann Cairns acairns@geosociety.org 303-357-1056 Geological Society of America Source:Eurekalert

1 GOOD

Page: 1 2 3 4 5 6 7 8 9 10
Related biology news :

1. September Geology and GSA Today media highlights
2. October Geology and GSA Today media highlights
3. November GEOLOGY and GSA TODAY Media Highlights
4. Heart of Herschel to be presented to media
5. Last chance for media to register for ECCO 14 -- the European Cancer Conference
6. Media highlights in the November issues of Biophysical Journal
7. Nanotechnology and the media: The inside story
8. Highlights from the September 2007 Journal of the American Dietetic Association
9. AGU journal highlights -- Sept. 6, 2007
10. IDEMA Reveals Program Highlights for DISKCON USA 2007
11. IDEMA Reveals Program Highlights for DISKCON USA 2007