About This Item

Share This Item

The AAPG/Datapages Combined Publications Database

AAPG Bulletin


Volume: 64 (1980)

Issue: 9. (September)

First Page: 1568

Last Page: 1568

Title: Log Evaluation of Wells in Tuscaloosa Trend of South Louisiana: ABSTRACT

Author(s): John Stevenson

Article Type: Meeting abstract


The Tuscaloosa trend of south Louisiana provides many challenges to oil and gas operators. The formations are found below a depth of 16,000 ft (4,877 m). At these depths, temperatures approach 400°F (204°C) and pressure gradients range from 0.459 to 0.96 psi/ft. Production tests have shown the presence of CO2 and H2S and have revealed that formation water salinity ranges from 11,500 to 120,000 ppm NaCl. These salinity variations occur both vertically and laterally.

The combination of depth, high temperature, and varying pressure gradients along with the presence of CO2 and H2S has complicated drilling, usually resulting in the use of oil-base mud below a depth of about 16,000 ft (4,877 m). The logging tools used to evaluate these formations must operate in this hostile environment. Various combinations of tools are applicable to Tuscaloosa evaluation, with limitations. Difficulties in calculation of formation water salinity arise from logs run in oil-base mud.

End_of_Article - Last_Page 1568------------

Copyright 1997 American Association of Petroleum Geologists