SPE-sponsored study endorses LWT’s operational, economic advantages
Nov. 29, 2018
Reliable data. Minimal risk. Virtually no extra rig time.
Those were the findings of a recently released Society of Petroleum Engineers (SPE) paper on Cordax’s proprietary Logging While Tripping (LWT) technology, whose case study focused on two ADNOC (Abu Dhabi National Oil Company) Onshore wells in Abu Dhabi.
“It is highly recommended using LWT conveyance and acquisition technology to acquire triple combo open-hole formation evaluation data to reduce overall data acquisition costs and lower the operation risk profile,” concludes the SPE paper, which was presented at the Abu Dhabi International Petroleum Exhibition and Conference in the United Arab Emirates in mid-November.
“In challenging downhole conditions, LWT technology will provide the useful desired formation evaluation data in cost-effective and time-efficient manner at a low risk,” the paper continues.
ADNOC Onshore applied Cordax’s LWT logging technology to a pair of onshore wells in order to assess its efficiency, reliability and the quality of LWT open-hole logging measurements acquired.
One of these wells was a 45-degree deviated oil producer, while the other was specifically selected due to the formidable risks encountered when logging with open-hole wireline (WL) or logging while drilling (LWD) through depleted zones and complex geological structures.
The SPE paper notes that Cordax’s LWT suite of logging tools includes Gamma Ray (GR), Spectral Gamma Ray (SGR), Compensated Neutron (CN), Formation Density (DEN), Induction Resistivity (DUIN) and Propagation Resistivity (PRT).
It also found the following:
The use of Cordax’s LWT technology saved nearly two rig days on well No. 2;
LWT log quality was equivalent to conventional open-hole WL and LWD log data;
Small variations in LWT versus WL and LWD log data were logically explained to be a result of differing logging timelines and the corresponding effect of mud invasion;
Comparison of LWT porosity with nearby offsetting well core porosity showed better reliability than LWD porosity.
Significantly, noted authors of the SPE paper, “Quality data has been acquired in both well No. 1 and well No. 2 with minimal risk and virtually no extra rig time.”