DETAILS OF TENTATIVE SCIENCE ISSUES

Already demostrated is the ability to do high resolution correlation and the practicality of obtaining time series of climatic proxies in Triassic-Jurassic continental sediments in the NSF funded Newark Basin Coring Project (NBCP) (Kent et al., 1995; Olsen et al., 1996; Olsen and Kent, 1996). Although efforts are underway to finally obtain comparable climatic records from the Quaternary and rest of the Neogene by others, it is essential to obtain comparably detailed records from more ancient times to understand the long term behavior of the climate system and its age-independent aspects. In addition, the climatic transect for Triassic-Jurassic Pangea can be obtained for longer time periods and at more modest expense than for virtually any other geologic period, including the Neogene.

The very high temporal resolution we have demonstrated in the Triassic-Jurassic basins in eastern North America in the NBCP suggests that the relationship between the Large Igneous Province (LIP) produced during the early Mesozoic initiation of the fragmentation of Pangea and the Triassic-Jurassic mass extinction can be established at level of temporal resolution comparable to or even better than that at the K-T boundary. The Triassic-Jurassic mass extinction is larger in magnitude than that at the K-T boundary and the Triassic-Jurassic LIP may be the largest of all time (Olsen, et al., 1997). At the present however the relationship between the volcanism and mass extinctions remains to be resolved. The specific question addressable in the Triassic-Jurassic basins can be phrased "Is there an important paleoclimatic transition associated with extinctions at the Triassic-Jurassic boundary and is it somehow related to LIP, a bolide impact, or some other process?"

The Triassic-Jurassic LIP is most likely associated with the earliest seafloor spreading in the break up of Pangea. The Triassic-Jurassic sedimentary basins responded to this major event in very different ways along what would become the Atlantic margins (Withjack et al, 1998). Again, the continuous coring records in the sedimentary basins coupled with high-precision dating will allow the pattern of basin responses and sea floor development to be worked out in a uniquely high-resolution and spatially wide-spread way.

While it is clear that the Triassic-Jurassic mass extinction was very large in magnitude (Olsen et al., 1987), its exact age remains in dispute. Because of the high resolution stratigraphy obtainable from these strata, floral (especially microfloral) change can be documented from cores, and faunal change can be obtained from outcrop. A detailed inventory of mass extinction data combined with coring can show us the pattern of biotic change around the boundary, potentially pole to pole.

The continuous deposition seen in many Triassic-Jurassic rifts and epicontinental basins allows for the recovery of astronomically calibrated paleomagnetic polarity records spanning tens of millions of years, as we have demonstrated for the Late Triassic with the NBCP (Kent et al., 1995). The early Jurassic polarity records from marine strata can potentially be coupled with continental records from the Triassic-Jurassic basins in the Pangean transect and high-precision dates, eventually providing a high resolution astronomically tuned polarity record for at least the entire Early Jurassic and Late Triassic.

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