Published in SEG 2013 DAILIES
There are many tough places to do seismic surveys. Kurdistan is one of them. However, Asian Oilfield Services Limited (AOSL), based in Gurgaon, India, chose to deploy Wireless Seismic’s RT System 2 seismic data acquisition system in this location because the combination of no cables and real-time data retrieval was ideal for the job and the assortment of conditions surrounding it. Wireless Seismic, Inc. (WSI), based in Sugar Land, Texas, produces the industry’s only fully scalable wireless recording system with real-time data transmission.
The 3D survey covers more than 300 sq km (116 sq miles) over a variety of terrains, from flat plains with villages to steep hills and rocky cliffs, in the southern area of the Kurdish Autonomous Region of Iraq. Laying cables can be logistically challenging in the region due to its rugged environment and very unpleasant working conditions — temperatures will easily reach 51.7 degrees Celsius (125 degrees Fahrenheit) during the day. And, even though the region is experiencing economic growth, remnants of the recent war are still a major concern regarding safety issues. The focus on reducing overhead and manpower was clearly a primary consideration.
RT System 2 is typically laid out in the general configuration of a cable system, with receiver in-lines and a cross-line backbone, which connects the individual receiver lines to the central recorder. The receiver in-lines of the wireless remote units (WRUs) transmit the data in a relay fashion towards the backbone. The backbone is also wireless, comprising high-bandwidth commercial radios. RT System 2 for the Kurdistan 3D survey consists of 7,500 channels with over 4,700 channels in a live patch. AOSL is deploying up to 525 stations on each receiver lines and up to 14 active receiver lines. Additional receiver lines are deployed and rolled into active status from the central recorder.
According to the company, the lack of cables is a logistical advantage when laying out the wireless seismic system, and the ability to view the data instantly has facilitated the assurance of complete, quality data. The observer has control and always knows what is happening with it. For example, when children in the villages were taking the antennas as playthings, the observer received a warning. In another instance, one line was interrupted by noise levels from road construction and the vibrators were placed on standby for a short while.
Regulations require a relatively high percentage of local hires for the crew. Some very basic training was necessary for the non-skilled local labor, including simple tasks as attaching geophones or batteries to the WRUs. Deployment has been much simpler than would have been the case with a cabled system, operating with a much smaller crew than would be required and with much lower HSE exposure. At times, the ground was so steep that the units had to be secured to stop them from sliding down the slopes.
In the recording cabin, there are some new skills involved in trouble shooting the wireless equivalent. Wireless Seismic has a team of highly experienced customer support engineers that provide training for RT System 2. They are used to working in jungle, arctic, and desert conditions while remaining sensitive to local customs and indigenous people. One or more WSI field service engineers are sent out with every system purchased until the customer is skilled enough to take over, as with the Kurdistan deployment.
The system has performed reliably on this project, and Rahul Talwar, CEO of Asian Oilfield Services, commented that “RT System 2 is living up to the promise of a truly real-time wireless system. Wireless Seismic has gone above and beyond expectations in their support of the system under very challenging conditions.”
To learn more about the Kurdistan and other RT System 2 deployments around the word, visit Wireless Seismic at Booth 712. To learn more about the system, visit www.wirelessseismic.com.