Einladung zum Vortrag
GEOLOGY IS ANCIENT LIFE
Current Evidence for the Earliest Life on Earth
Ein Vortrag von
Prof. Dr. Don LOWE
(Professor at the Department of Geological and Environmental Sciences, Stanford University, California)
Montag, 16. Juni 2008 um 15:00 Uhr
Geologische Bundesanstalt, 1030, Neulinggasse 38, Vortragssaal
Summary
While microbial stromatolites and microfossils provide abundant evidence that life was flourishing 3.0 billion years ago, the record of still earlier life, between about 3.8 and 3.0 Ga, is spotty and controversial. The most ancient rocks in West Greenland are highly metamorphosed and putative signs of life have been reinterpreted as the products of metamorphism. Younger greenstone sequences, 3.5-3.2 billion years old, contain a variety of biosignatures, including organic carbon with C-isotopic values suggesting organic processing and sparse microfossils and stromatolites. However, most of these occurrences have also been interpreted as reflecting abiotic processes related to carbon processing in hydrothermal systems. The first well-developed carbonate stromatolites are developed in rocks 3.0 billion-years old. These may represent the oldest, unambiguous evidence for terrestrial life but it seems likely that microbes were alive, well, and interacting with their environment, perhaps under surface temperatures as high as 70°C, at least 500 million years earlier.
Donald R. Lowe
is Professor at the Department of
Geological and Environmental Sciences at Stanford
University (California, US).
Education:
- B.S.: Geology (with Honors), Stanford University, 1964
- Ph.D.: Geology, University of Illinois, 1967
Experience:
- 1968-70: Postdoctoral Associate, US Geological Survey, Menlo Park, CA
- 1970-73: Assistant Professor, Department of Geology, Louisiana State University, Baton Rouge, Louisiana
- 1973-78: Associate Professor, Department of Geology,LSU
- 1978-88: Professor, Department of Geology, LSU
- 1988-present: Professor, Department of Geological and Environmental Sciences, Stanford University, Stanford, California
Recent professional activities:
- 1983-1993: Editorial Board, GEOLOGY
- 1990-1991 Chairperson, Sedimentary Geology Division, Geological Society of America
- 1993-present Co-Director of Stanford Project on Deep-Water Depositional Systems (SPODDS)
- 1995-1997 Member, GSA Committee on the Penrose Medal Award
- 1997 Invited Participant, SEPM Debate at Annual AAPG-SEPM Meeting: Processes of Deep-Water Clastic Sedimentation and Their Reservoir Implications: What Can We Predict?
Some recent publications:
- Krull-Davatzes, A.E., Lowe, D.R., and Byerly, G.R., 2006, Compositional grading in an ~3,24 Ga impactproduced spherule bed, Barberton greenstone belt, South Africa: A key to impact plume evolution: South African Journal of Geology, v. 109, p. 233-244.
- Lowe, D.R., and Tice, M.M., 2007, Tectonic controls on atmospheric, climatic, and biological evolution 3.5-2.4 Ga: Precambrian Research, v. 158, p. 177-197.
Website:
http://pangea.stanford.edu/research/SPODDS/Faculty/Lowe/
© Österreichische Geologische Gesellschaft
