A novel integrated approach to estimating hydrocarbon saturation in the presence of pore-lining chlorites

作者:Tudge Joanne*; Lovell Mike; Davies Sarah; Millar Mike
来源:Petroleum Geoscience, 2014, 20(2): 201-209.
DOI:10.1144/petgeo2013-044

摘要

Pore-lining chlorites are often associated with a low-resistivity contrast between corresponding reservoir units, making the identification and quantitation of hydrocarbon-bearing intervals difficult. In many low-resistivity situations, the traditional approach of using Archie%26apos;s equation to determine saturation from electrical resistivity fails, and modified Archie equations derived specifically for %26apos;shaly sands%26apos; have been developed. In chlorite-bearing intervals, however, the effect of chlorite can be such that both Archie and the so-called shaly-sand models are inappropriate. Under these circumstances, calculating saturation from electrical resistivity can be circumvented by detailed analysis of the sedimentology and petrophysics, enabling the construction of a saturation height model based on core data. In this novel study we integrate a detailed core-based sedimentological facies scheme with wireline log data and petrophysical core data to demonstrate a clear link between chlorite occurrence, petrophysical characteristics and saturation height. Through this innovative approach, saturation is estimated without recourse to resistivity logs and improves hydrocarbon saturation estimates in chlorite-bearing reservoirs.

  • 出版日期2014-5