Halliburton provided reliable data when no one else could

Overview 

A major oil and gas company in the Asia-Pacific region wanted to increase production from an offshore well that had been completed 12 years ago. The company drilled a sidetrack to a pay zone that was originally bypassed. However, during cementing, gas seeped into the cement, which made cement evaluation of the sidetrack challenging. The operator needed assurance that an accurate cement evaluation could be provided in this gas-contaminated well. Halliburton recommended its CAST-M™/CBL-M tool combination to collect the data and its Advanced Cement Evaluation (ACE™) software to process it. The combination of technologies helped the operator accurately evaluate the cement job and verify cement bond conditions. The speed and accuracy of the job led to client trust and the use of the CAST-M/CBL-M tool combination in future wells. It also marked Halliburton’s successful re-entry into the area.

Challenge: Acquire Better Understanding of Reservoir Characteristics in Unconventional Play 

Reliable cement evaluation is important for any well, but can be critical when dealing with cement that has been contaminated with gas. In order to ramp up production in an offshore well and produce additional hydrocarbons, a major oil and gas company in the Asia-Pacific region drilled a sidetrack from the existing offshore well. However, because the drilling mud had been contaminated with gas, ensuring a reliable cement bond proved challenging. Gas can interfere with the cement and its ability to properly set, causing integrity issues that could impact the future of the well. Gas contamination also decreases the accuracy of cement evaluation needed to determine proper cement bond. Previous evaluations did not provide the information the operator needed to ensure zonal isolation, and the company wanted to make sure it had accurate information before it started production. The operator hired Halliburton to provide a unique solution to this challenging situation.

Solution: The CoreVault^® RFP System Offers a Direct View Into Well Productivity

Evaluation of lightweight cement can be challenging. Halliburton used its ACE software to help accurately interpret the data from the CAST-M™/CBL-M tool combination. This dedicated cement evaluation processing software evaluates raw data variance to help determine the presence, or lack, of cement behind the pipe. ACE software incorporates a statistical variance-mapping product for both sonic and ultrasonic tools. The resulting variance image detects minor changes in cement or fluid composition and helps distinguish cement from liquid. This technique accurately evaluates cement bond and channels in cement.

Result: CoreVault RFP Findings Enrich Understanding of the Reservoir’s Economic Value 

Without formal operations in this area for a number of years, Halliburton Wireline and Perforating quickly assembled the personnel and equipment needed to conduct the logging operation. Halliburton completed the job the first time, with no need for multiple trips and no NPT, saving the operator time and money. The accurate evaluation also helped the operator get the answers it needed to perforate the sidetrack and restart production. 

Despite challenging conditions, Halliburton proved the effectiveness and accuracy of its cement evaluation services in gas-contaminated wells. The CAST-M/CBL-M tool combination along with ACE software provides a complete cement evaluation service that can be a game changer in the Asia-Pacific region. The operator believes Halliburton delivered accurate results with a high level of confidence. Halliburton has become a trusted advisor that the operator can turn to for cement evaluation in future wells.