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Simon Klemperer
Professor of Geophysics
and, by courtesy, of

Geological and Environmental Sciences
Mitchell Building, room 353
Stanford, CA 94305-2215
email: sklemp at stanford.edu
phone: (650) 723-8214
fax: (650) 725-7344





We welcome applications from both geologists and geophysicists to join our group, and have funded research opportunities for undergraduates and for a post-doctoral research associate

 

CLASSES TAUGHT AT STANFORD

Complete Listing of Courses and Degrees in Geophysics


RESEARCH

Klemperer leads the Stanford Crustal Geophysics Group. We are interested in regional tectonics at crustal and lithospheric scales, and in the structure, composition and development of the lithosphere, particularly of the continents. Most of our work uses controlled-source seismic profiling (reflection or refraction), though we employ other geophysical techniques when appropriate, including teleseismic methods, and we attempt to integrate geological information closely into our models. We even take field trips to learn about the geology we are studying!

Closely co-operating faculty are Professors George Thompson and Norm Sleep, and Consulting Professors Walter Mooney and Dave Scholl. Post-doc Marleen Nyst is associated with our group.  Research students are Katie Keranen, Ewenet Gashawbeza, Derek Lerch and Nathan Fung. Research students working on joint projects between the Crustal Group and the Stanford Exploration Project are Brad Artman and Gabriel Alvarez. Research students working on joint projects between the Crustal Group and the Structural Geology and Tectonics Group are Derek Lerch and Joe Colgan.  Stanford undergraduates carrying out research in our group are Roland Gunther, Andrea Les and Michele Cash.   In academic 2002/2003 we welcomed Visiting Prof. Andy Nyblade, on sabbatical from Penn State, to our group; in 2004/2005 Visiting Prof. Andy Calvert from Simon Fraser University; and in 2005/06 Visiting Prof. Bob Stern from UT Dallas.

Post-doctoral alumni of the Stanford Crustal Geophysics group are: Charles Wilson (now at Lamont), Bruce Beaudoin (now at the PASSCAL Instrument Center), John Hole (now Professor Hole at VPI), Andrew Long (now with PGS-Seres in Perth, Australia) and Ginger Barth (now at the U.S. Geological Survey).
Recent Ph.D. students from the Stanford Crustal Geophysics group are: Seth Haines (now with U.S. Geological Survey), Kris Walker (now at Scripps Institute of Oceanography), Darcy Karakelian (now with the U.S. Geological Survey), Moritz Fliedner (now with 3D-Geo), Nikki Godfrey (now with Landmark Geophysics), and Yizhaq Makovsky (now with Paradigm Geophysical).

We welcome applications from both geologists and geophysicists to join our group, and have funded research opportunities for undergraduates.

Much of our work is field-based. Some of our active collaborations are:

In TIBET:
Project INDEPTH (International Deep Profiling of Tibet and the Himalaya): We carried out field seasons in 1992, 1994 and 1997 to acquire seismic data in southern and central Tibet, working with colleagues from Cornell, Syracuse and New Mexico State Universities, and scientists from China and Germany. We have imaged continental crust being subducted beneath Asia along the Main Himalyan Thrust e.g. (Alsdorf et al., 1998; Makovsky et al., 1999) but shown that older sutures in central Tibet (the Bangong-Nujiang suture) may have been obliterated by lower-crustal flow (e.g. Haines et al., 2003). We also discovered bright reflections from large volumes of aqueous fluids in the mid-crust, probably associated with recent and active granite melting and intrusion in the thickened Tibetan crust, above the subducting Indian crust (Makovsky & Klemperer, 1999).   Our next field season in 2007 (INDEPTH-IV) will collect reflection and refraction data across the northern margin of the Tibet plateau.
 
In NORTHWESTERN NEVADA :
A study of the extension paradox at the northwest margin of the Basin-&-Range Province: In September 2004 we acquired a 250-km long refraction/reflection seismic profile at 40.5N across the northernmost Basin and Range province, funded by the National Science Foundation and the Petroleum Research Fund. This was nominally the first experiment to use the "FlexArray" of the USArray component of EARTHSCOPE, and we deployed over 1100 seismographs. Although the average elevation of the Basin-&-Range does not change significantly over 150 km from southernmost Oregon to central Nevada, the degree of extension increases from c. 15% to c. 150% over the same distance. We believe the lower crust beneath northern Nevada is flowing south to central Nevada (or did at some time in the past), equalizing the crustal thickness and balancing the elevations across this region. Our new seismic profile will test this hypothesis by measuring the crustal thickness and structure in great detail across northwestern Nevada, including efforts to image lower-crustal laminations and to measure lower-crustal anisotropy. Stanford graduate students Joe Colgan, Derek Lerch and Ewenet Gashawbeza are working on this project.

In ETHIOPIA:
US-EAGLE (Ethiopia-Afar Geoscientific Lithospheric Experiment) is the US component of the international EAGLE program to investigate modification of lithospheric structure during continental breakup.  With US collaborators from UTEP, Penn State and SWMSU we will work with UK scientists from Leicester, London, Leeds and Edinburgh in a comprehensive investigation of the deep structure of the Main Ethiopian Rift, at the point where the archetypal narrow continental rift - the East African Rift - is becoming dominated by magmatism as it progresses towards ocean rifting in the Afar Triangle and southern Red Sea.  Stanford graduate students Katie Keranen and Ewenet Gashawbeza, and undergraduates Michele Cash and Andrea Les, are working on this project.  For more on the science objectives of the project, click here. In June 2004 I co-organized the NSF-funded US-Africa Workshop on Anatomy of Continental Rifts: The evolution of the East African Rift System from nascent extension (Okavango Rift Zone) to continental breakup (Afar Depression) in Addis Ababa, Ethiopia.
BBC Radio Program describing the EAGLE project

In the WESTERN PACIFIC :
Multi-scale seismic imaging of the Mariana Subduction Factory: we acquired seismic wide-angle and near-vertical reflection data along and across the Mariana magmatic arc and forearc in a April 2002 cruise of the R/V Ewing, using equipment from the OBSIP pool.  Our recent experiment was the largest deployment of US ocean-bottom seismometers yet achieved: we dropped and successfully recovered 53 OBS.  Our data will provide the best-yet constraints on the structure and composition of an intra-oceanic arc system, as part of our scientific objective of understanding the Izu-Bonin-Mariana"subduction factory".  Our work is collaborative with University of Hawaii (responsible for additional reflection-seismic and bathymetric data acquisition), Washington University St. Louis and Scripps (responsible for aditional broadband passive seismic recording) and JAMSTEC (linking Japanese scientists to all our activities). Stanford graduate student Bryan Kerr and undergraduates Tawni Tidwell and Roland Gunther worked on this project.

In addition to participating in large-scale field programs, many students in the Crustal Researtch Group develop their own projects, including passive seismology to study mantle flow around hot-spots; electroseismic prospecting; and electromagnetic monitoring of earthquakes.
 

Other recent research collaborations include:

In CALIFORNIA:
Mendocino Continental Dynamics program: we acquired seismic data onshore and offshore California around the Mendocino Triple Junction, designed to study the effects on the crust of the northward passage of the triple junction along the US West Coast, and also the deep crustal structure of the Great Valley and Coast Ranges. We have shown that the Great Valley Basin and the underlying Great Valley Ophiolite were accreted by obduction onto underlying continental crust (Godfrey et al., 1997).
Southern Sierra Nevada Continental Dynamics program: we conducted seismic experiments and petrological studies to understand the deep crust of the Sierra Nevada, work which shows that this young mountain belt is not supported by an isostatic root. We have shown that the crust of this Mesozoic continental arc is unusually silicic, with velocities well below the continental average, and we therefore suggest that a mafic counterpart to the granitoids that compose almost the entire crust has been delaminated or was eclogitised so that it is now seismologically indistinguishable from mantle (Fliedner et al., 1996 & in press).

In ALASKA:
Aleutian Working Group: While Sue McGeary (University of Delaware) acquired marine reflection profiles along the Aleutian island arc, we recorded the seismic energy from the airgun sources on seismometers that we installed on the Aleutian islands. Steve Holbrook (University of Wyoming) simultaneously recorded the same seismic sources on ocean-bottom seismometers. We have shown that the crust of the intra-oceanic Aleutian arc is more mafic than average continental crust (Fliedner & Klemperer, 1999), but that the same arc developed within young continental crust of the Alaskan Peninsula is producing crust more compatible with the typical continental crust, suggesting that multiple episodes of intrusion and fractionation are required to generate the continents (Fliedner & Klemperer, in press).
Bering-Chukchi Working Group: In collaboration with Stanford geologists Prof. Elizabeth Miller and USGS geologists and geophysicists Jon Childs, Art Grantz, and Tom Brocher (USGS), together with scientists from Russia, we acquired the first multichannel deep seismic reflection profile to traverse the entire North American continent, recorded at sea through the Bering Straits, from the oceanic crust of the Aleutian Basin to the Arctic Ocean. Interpretation of these profiles is being aided by an ongoing program of field mapping, petrological, geochronological and xenolith studies in both Alaska (the Seward Peninsula) and the Russian Far East (the Chukotsk Peninsula). Our GIS compilation of geologic and geophysical data for the region was released as a CD-ROM in 1999 (Greninger et al., 1999).

Click here to see a selection of PUBLISHED PAPERS for Simon Klemperer.


 
 

ACADEMIC HISTORY
1980 B.A. Mineralogy and Petrology, Cambridge University
1985 Ph.D. Geophysics, Cornell University

PROFESSIONAL EXPERIENCE
1985-90 Research Associate, BIRPS, Cambridge University
1990-present Associate, now Full, Professor of Geophysics, Stanford University
1999-2000 Visiting Professor of Geology, Royal Holloway, University of London

HONORS AND AWARDS
1982-84 Milton Dobrin Scholar, Society of Exploration Geophysicists
1987-90 Royal Society University Research Fellowship
1988 President's Award of the Geological Society of London
1995 Fellow of the Geological Society of America

COMMUNITY SERVICE
1996: convenor, "7th International Symposium on Deep Seismic Profiling of the Continents" at Asilomar, California
1992-1998: Director of the national seismograph facility, the PASSCAL Instrument Center (now re-located to New Mexico)
1998-2004: member of the NSF Continental Dynamics review panel
1998-2002: member of the NSF combined Ocean Sciences and Earth Sciences MARGINS Science Steering Committee
2002: co-convenor, MARGINS Izu-Bonin-Mariana Subduction Factory workshop, Hawaii, September 8-12
at Stanford:
1990-1999 Director, MSED Program (Master of Science in Exploration and Development), the Geophysics Department's focused 4-quarter, 16-month Master's program leading to careers in the oil-exploration industry.
1993-1999 Director, Earth Sciences Geographic Information Systems (GIS) laboratory, a school-wide initiative to make the latest software for image processing, remote sensing, and 2D and 3D GIS available for research and teaching.
2001: convenor, "The Lithosphere of Western North America, and its Geophysical Characterization" (The George Thompson Symposium)
 
 


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