SEQUENCE STRATIGRAPHY

Stratigraphic sequences are the framework within which all reconstructions of past global change are made. In addition, sea level change acts as a master variable for a wide range of processes in epicontinental settings and relative sea level-controlled changes in sediment delivery appear to have effects extending well into the oceanic realm.

As such, a significant portion of my research effort is directed at understanding the nature of, and controls on stratigraphic sequences. I have contributed to the body of work concerning sea level history in the Western Interior basin through studies of Cenomanian-Turonian organic carbon- and skeletal-rich deposits in distal settings (e.g., Sageman, 1996; larger version of Fig. 4 from that paper), as well as to studies of the coeval Cenomanian-Turonian shorelines (Elder et al., 1994; Laurin and Sageman, 2001).

A collaborative study of the Permian Brushy Canyon Formation in West Texas was essentially a test of the condensed section paradigm in a slope and basin floor fan environment. Here we used trends in organic carbon richness to help quantify a stratigraphic hierarchy for the deep water depositional system that my colleague Mike Gardner and his team had been working on (see Sageman et al., 1996). Similarly, as part of a collaborative study of the black shales of the Devonian Appalachian basin I worked with Chuck Ver Straeten and Carlton Brett on the integration of petrologic, mineralogic, and geochemical data to refine sequence stratigraphic interpretations of the Givetian - Frasnian interval in west-central New York.

My most recent work on stratigraphic architecture has involved collaboration with two humans who are, coincidentally, both from the Czech Republic. Jiri Laurin came over on a Fulbright in 2000 and his study of the Cenomanian-Turonian paralic section in SW Utah became a significant part of his Ph.D. thesis from the Charles University (co-advised by Dr. David Ulicny). He now holds a position at the Czech Academy of Sciences and we continue to collaborate on Cenomanian-Turonian sequence stratigraphy. Petra Pancoskova completed a Master's thesis on the Santonian Emery Sandstone in central Utah and her work is contributing to a larger synthesis of Coniacian-Santonian stratigraphy that current doctoral student Rob Locklair is working on.

One of the most excting new developments in my stratigraphic research has been the result of a seminar team taught by Steve Meyers, Jiri Laurin and myself in 2003. This new work blends 2-D stratigraphic modeling with advanced spectral analysis techniques to explore the relationship between marginal marine and hemipelagic parts of epeiric sea depositional systems that are forced by orbitally influenced climate changes (see orbital forcing of climate and sedimentation and Laurin et al., 2005).