Stratigraphy, the study of sedimentary basin architecture and correlation between basins, is closely tied to sedimentary petrology, paleontology, geochemistry, and geobiology. Our research programs in stratigraphy are highly diverse.  Some of our research interests include:

1. The stratigraphic setting for the emergence of metazoa (animals).

The cause of the explosive diversification of animals at or near the Precambrian-Cambrian transition remains one of the most interesting questions in paleobiology.  An understanding of the stratigraphic setting is crucial if we wish to unravel the causes and effects of this extraordinary transition in the history of life.  A combination of sequence-, bio-, and chemo-stratigraphy is currently used to piece together the stratigraphic context of the Cambrian explosion.  Major field sites include the southern Great Basin (USA), Caborca (Mexico), and several provinces in China.

1. The consequences of extreme environmental perturbations (e.g., “Snowball Earth” and mass extinction/recovery).

A growing body of evidence would suggest that the earth has experienced environmental extremes not predicted via standard uniformitarian views.  One such extreme, as evidenced by thick low-latitude glaciomarine sediments (e.g., glaciers in the tropics!), took place in Neoproterozoic time (ca. 750 Ma-565 Ma), and is commonly termed “Snowball Earth."  The effect of low-latitude glaciation on the sedimentary record and the history of life is currently studied in the Great Basin (USA), Sonora (Mexico), Namibia, and China, as well as via computer climate modeling.
The stratigraphic context of mass extinctions and their aftermath comprises another component of stratigraphic study.  Currently, we are studying the end-Permian, end-Triassic, and end-Jurassic extinctions and recoveries in the Great Basin (USA), Japan, and Morocco, and the Cretaceous-Tertiary extraterrestrial impact layer in Central America.

1. The study of time-patterns and climate signals in sedimentation.

Biogenic sediments (chalk, siliceous ooze, oil shale) are sensitive recorders of climatic fluctuations. Such deposits commonly contain rhythmic laminations, with periods that range from annual varves to cycles at the 500,000 year level. The time domain between the observational spans of meteorology and oceanography and those of conventional geology remains largely unexplored.  We seek to define the forces that drive sedimentary change (which lie partly in solar cycles and partly in the earth's orbital variations, but may include other factors), and to develop high-resolution geochronologies based on these cycles. While much of the work has been in Cretaceous sediments, the Eocene Green River oil shales, the Monterey Formation, and the varved deposits of the Santa Barbara basin offer interesting prospects. 

Students in sedimentary petrology and stratigraphy are encouraged to develop a strong background in geochemistry, marine geology, applied statistics, and paleobiology in addition to sedimentology.  All major land and sea-based equipment needed to perform such research is available within the Department or the University.  Additional equipment can be located at other universities in the Los Angeles area.