Computer-generated lithology-porosity calculations based on corrected sonic, density neutron, and gamma-ray logs can aid greatly in interpreting the rock record. Percentage shale calculations averaged over uniform intervals show one-to-one correlation with environmental interpretations derived from micropaleontologic data for Upper Cretaceous rocks in the COST GE-1 well. For the marine section percentage quartz parallels percent shale and both follow the general trend of transgressions and regressions suggested by P. Vail et al.

The transgressive pulses at the GE-1 site are quite similar to those at the B-2 site. The depositional sequence is similar at the two sites, with both containing Upper Cretaceous shelf carbonates, Lower Cretaceous nonmarine clastics, and a decreasing rate of deposition with time.

Lower Cretaceous Albian anhydrite present at GE-1 is absent at B-2. Conversely Lower Cretaceous coal,

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abundant at the B-2 location, is absent at GE-1. Given the otherwise similar stratigraphic sections, these differences are believed mainly climatic in origin. Porosity in GE-1 Lower Cretaceous sands shows only slight decrease with depth.

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