Formation evaluation

Cased-Hole Standalone Evaluation Succeeds in the Absence of Openhole Data

The paper outlines examples from tight gas reservoirs in two fields in which openhole data was unavailable and petrophysical analysis was undertaken using cased-hole data.

Pump jacks  with a pressure gauge
Oil Wellhead
Huyangshu/Getty Images/iStockphoto

Accurate petrophysical evaluations (formation lithology, porosity, and water saturation) are essential in characterizing potential reservoir zones and estimating resources in place. Typically, these evaluations rely on acquisition of openhole logging measurements; however, this is not always possible. The complete paper outlines two examples from tight gas reservoirs in two separate fields offshore Abu Dhabi in which openhole data could not be acquired and petrophysical analysis was undertaken using cased-hole log data. These evaluations successfully identified gas-saturated porous intervals in each well, one of which was successfully flow-tested.

Introduction

A growing need exists to increase gas production in the UAE. As a result, specific gas-production targets have been mandated from development of currently undeveloped deep gas carbonate reservoirs such as the Permo-Triassic Khuff formation, the middle Jurassic Araej formation, and the Permian Pre-Khuff Unayzah and Berwarth formations.

SPE_logo_CMYK_trans_sm.png
Restricted Content
We're sorry, but this content is reserved for SPE Members. If you are a member, please sign in for access. If you are not a member and you find JPT content valuable, we encourage you to become a part of the SPE member community.