2008 Joint Meeting of The Geological Society of America, Soil Science Society of America, American Society of Agronomy, Crop Science Society of America, Gulf Coast Association of Geological Societies with the Gulf Coast Section of SEPM

Paper No. 10
Presentation Time: 10:30 AM

Confidence Intervals on Stratigraphic Ranges When Recovery Potential Is Unknown

WANG, Steve C.1, EVERSON, Philip J.1, CHUDZICKI, David J.2 and PARK, Dasol1, (1)Mathematics and Statistics, Swarthmore College, 500 College Ave, Swarthmore, PA 19081, (2)Mathematics, University of Chicago, 5734 University Ave, Chicago, IL 60637, scwang@swarthmore.edu

Several existing methods for estimating the true stratigraphic range of a fossil taxon require the assumption of uniform fossil recovery potential — that fossils are equally likely to be found at any point within the taxon's true range. This assumption is unrealistic, because factors such as the taxon's abundance and the amount of fossiliferous rock outcrop affect recovery potential. Other methods do not make this unrealistic assumption, but they instead require a priori quantitative knowledge of recovery potential that is often difficult to obtain. We present a method for estimating the true stratigraphic range of a taxon that works for both uniform and non-uniform recovery potential. In contrast to existing methods, we estimate fossil recovery potential from the data itself, so that a priori knowledge of recovery potential is not required. Using simulated datasets, we assess the performance of our method under a variety of conditions.