of normal and thrust faulting; earthquake source mechanics; Cenozoic tectonics
of the southern Colorado Plateau and transition zone; earthquake studies of the
North Anatolian fault zone, Turkey, and the Aleutian plate boundary.
interests lie in the fields of structural geology and tectonics and are quite
broad. All of my research projects are strongly field based and many are
augmented with petrographic, microstructural, and microprobe work. In addition,
I work regularly with U/Pb and 40Ar/39Ar geochronologists to constrain the
timing of deformational events. I currently have two active research projects.
accretionary tectonics in the southwestern U.S. The period between 1780 and
1650 Ma was one of major crustal growth in North America. Crustal growth
occurred by the generation, collision, and amalgamation of juvenile crustal
material such as oceanic island arcs and their associated basins, magmatic
additions to the crust through rifting and, possibly, the involvement of
fragments of older continental crust. This accretionary episode was similar in
scale to the addition of numerous “suspect” terranes to western North America
in the Mesozoic. A complicated and enigmatic boundary zone between the Mojave
and Yavapai Proterozoic crustal provinces occurs in northwestern Arizona.
Determining the timing and mode of juxtaposition those provinces and the manner
in which isotopically mixed crust is formed are the primary objectives of this
extensional tectonics in southern Nevada and northwestern Arizona. The Lake
Mead area, southern Nevada and northwestern Arizona, has been the locus of
large-magnitude extension (perhaps as much as 300%, according to some workers)
in the middle Miocene and studies in this region have been the basis for
development of several models for crustal extension. A major question has
centered on the types of structures that have accommodated extension,
specifically, the relative roles of strike-slip and detachment faulting. An
outgrowth of this project focuses on how along-strike variations in
displacement along large-scale, low-angle normal fault systems (detachments)
E.M., Chamberlain, K.R., and Fry, B., 2006, Mojave-Yavapai boundary zone,
southwestern United States: A rifting model for the formation of an
isotopically mixed crustal boundary zone: Geology, v. 34, p. 681-684>
E.M., Chamberlain, K.R., and Heizler, M., 2006, Filling the North American
Proterozoic tectonic gap: 1.60-1.59 Ga deformation and orogenesis in southern
Wyoming, USA.: Journal of Geology, v. 114, p. 19-42.
J.E., and Duebendorfer, E.M., 2005, Origin and trajectory of the Frenchman
Mountain block, an extensional allochthon on the Basin and Range province,
southern Nevada: Journal of Geology, v. 113, p. 355-371.
C.B., Duebendorfer, E.M., and Chamberlain, K.R., 2004, Synkinematic intrusion
of the 1.4 Ga Boriana Canyon pluton, northwestern Arizona: Implications for ca.
1.4 Ga regional strain in the western U.S.: Journal of Geology, v. 112, p.
E.M., 2003, The interpretation of stretching lineations in multiply deformed
terranes: An example from the Hualapai Mountains, Arizona, USA: Journal of
Structural Geology, v. 25, p. 1393-1400.
E.M., and Vazquez, K.L., 2002, Penetrative strain at shallow crustal levels:
The role of pressure solution in accommodating regional shortening strain,
Ventura basin, western Transverse Ranges, California, in Barth, A., ed.:
Crustal evolution of the southwestern United States: Geological Society of
America Special Paper 365, p. 295-314.
E.M., 2002, Regional correlation of Mesoproterozoic structures and
deformational events in the Albany-Fraser orogen, Western Australia:
Precambrian Research, v. 116, p. 129-154.
E.M., Chamberlain, K.R., Jones, C.S., 2001, Paleoproterozoic tectonic history
of the Mojave-Yavapai boundary zone: Perspective from the Cerbat Mountains,
northwestern Arizona: Geological Society of America Bulletin, v. 113, p.
S.S., Duebendorfer, E.M., and Deibert, J., 1998, 40Ar/39Ar age determinations
from Miocene volcanic rocks in the western Lake Mead area and in the southern
Las Vegas Range: Canadian Journal of Earth Sciences, v. 35, p. 495-503.
E.M., and Sharp, W.D., 1998, Variation in extensional strain along-strike of
the South Virgin-White Hills detachment fault: Perspective from the northern
White Hills, northwestern Arizona: Geological Society of America Bulletin, v.
110, p. 1574-1589.
E.M., Nyman, M.W., Chamberlain, K.R., and Jones, C.S., 1998, Proterozoic rocks
within the Mojave-Yavapai boundary zone, northwestern Arizona: Comparison of
metamorphic and structural evolution across a major lithospheric(?) structure.
Duebendorfer, E.M., ed., Geologic Excursions in Northern and Central
Arizona: Geological Society of America, Field Trip Guidebook, p. 127-148.
E.M., Beard, L.S., and Smith, E.I., 1998, Restoration of Tertiary deformation
in the Lake Mead region, southern Nevada, in, Faulds, J., and Stewart, J.,
eds., Accommodation zones and transfer zones: The regional segmentation of the
Basin and Range province: Geological Society of America Special Paper 323, p.
E.M., Vermilye, J., Geiser, P.A., and Davis, T.L., 1998, Evidence for aseismic
deformation in Southern California: Implications for seismic risk assessment:
Geology, v. 26, p. 271-274.
E.M., and Rees, M.N., 1998, Evidence for Cambrian deformation in the
Ellsworth-Whitmore Mountains terrane, Antarctica: Stratigraphic and tectonic
implications: Geology, v. 26, p. 55-58.
My research is focused on Tectonics, especially active and
young tectonics of Late Cenozoic time. My main research interest is in the
tectonic evolution of, and processes that form, oblique plate boundaries. More
specifically, I study basins and related faults that form in these settings,
and the processes and evolution of areas with mixed strike-slip and dip-slip
faulting. My research is field based and my students and I use the methods of
structural geology, stratigraphy, and related disciplines to understand tectonic
problems. The research I conduct is inevitably collaborative with researchers
in many other fields, but especially in paleontology, sedimentology,
geochronology, petrology, marine seismology, geodesy, and paleomagnetism.