ADVANTAGES OF ENHANCED DATA LOGGING

Abstract

Rapid technologic evolution in the period from about 1955 to 1966 has been followed by considerable developments in exploration techniques. In recent years sophisticated data gathering and processing systems in seismic, gravity and magnetic methods, and in wireline logging, have become routine.

The validity of interpretations drawn from such data is critically dependent on the care exercised at the data acquisition stage. Because of generally large subsequent processing costs, there is now considerable emphasis on in-field verification of acquisition procedures by highly experienced explorationists.

A notable exception generally occurs during the drilling stages of an exploration programme. At present, such data acquisition is generally only carried out on relatively high cost offshore operations where it was first employed for safety reasons. However, geologists of limited experience generally still are given the responsibility of on-site verification of data.

It is possible now to monitor fully and digitally record all data, control and optimize drilling parameters and economics, and, in so doing, obtain data which may subsequently be used as basic input to more complete section evaluation.

Tangible benefits arise in the following areas : (a) increased drilling efficiencies generally lead to a significant reduction in total cost per foot; (b) substantial improvements in primary and secondary safety during drilling.

Intangible benefits which may arise include : (a) direct interpretation of wireline logs and drilling parameter logs to yield quantitative source richness (TOC) and maturation (LOM) of shales; (b) improved interpretation of reservoir properties to allow better prediction of ultimate performance and superior design of stimulation programmes.