Oil and Gas Middle East – July 2023
The Middle East and North Africa region is the largest oil-producing location in the world with its share of global crude oil production set to rise even further from one-third today to close to two-thirds in 2050 .
As offshore oil and gas reserves continue to deplete, greater precedence is being placed on onshore fields where operators can acquire greater hydrocarbon recovery. A recent industry report highlighted this move, noting that the global share of conventional onshore production is set to increase from around 50% today to about 56% by 2050, while the share of offshore production declines slightly from around 33% to 29%.
Onshore exploration brings a new set of challenges when compared to offshore and it is essential that operators thoroughly understand the subsurface using high-resolution seismic data to de-risk investment decisions. Conventionally, land seismic surveys have relied on complex and intrusive cabled geophone receiver systems which traditionally incur substantial CAPEX and OPEX costs due to expensive equipment, large crews, and long survey durations. The use of cabled geophones also carries sophisticated algorithms and labour-intensive processing to handle the intricacy of land data processing.
These factors have limited the type and coverage of onshore seismic data acquisition in traditional industries, often resulting in compromises on subsurface image quality, and sparse seismic data to effectively support new discoveries. However, with the introduction of cable-less receiver technology, geophysical providers and operators can now acquire dense, high-quality data much more efficiently and with less cost, risk, people, and environmental impact.
Effective seismic planning
During a recent project in Northern Iraq, STRYDE, a global expert in onshore seismic
acquisition technology and solutions, engaged with oil and gas operator DNO and its seismic contractor to deploy STRYDE’s seismic sensor technology. The operator required a seismic survey to obtain a 3D image of the subsurface for oil exploration and well-planning purposes. To achieve DNO’s operational plans for drilling the next well in their licensed area it was essential to reduce the seismic project turnaround time to pinpoint the best drilling location and fast-track decision-making.
Historically, the company had used cabled geophones to acquire seismic data but
experienced several challenges related to cost, time, and operational risk. DNO
subsequently chose to deploy modern, lightweight nodal technology for the first time on a major large 3D survey, to reduce costs, project cycle time, and risk – with a goal of accelerating access to high-resolution seismic data for rapid decision making.
To add to the project complexity, the terrain in the survey area was mostly made up of
gullies, mountain ridges, and rivers, requiring extensive pre-planning to limit vibroseis trucks to ridges for safe operations and to avoid the use of alternative dynamite sources to infill inaccessible source areas. To minimise any further pre-planning requirements and deployment time, it was crucial to use receiver technology that was easy to transport and quick to deploy on foot. Due to the reduced cost, compact size, and lightweight of the STRYDE Nodes™, this deployment method was able to be achieved very efficiently and DNO was able to increase the density of the receiver spread to acquire a better seismic image, when compared to previous surveys.
Reduced personnel for efficient deployment
A pseudo-orthogonal survey design over 250 sqkm2 defined a receiver line spacing of 200 meters with 25m receiver point intervals which resulted in 47,427 receiver stations in total. Source lines followed ridges within the complex terrain with 26,153 source points in total acquired along an irregular geometry with nominal 400m line spacing at 25m shot point intervals. Maximum offsets were set to 4,500 meters based on the depths of the target.
Using nodal technology requires less personnel on site and therefore helps to minimise the exposure to potential HSE risks by having less crew in the field, less driving, and minimal line clearing. In this project, six teams of three people were able to deploy enough nodes in the field to start source acquisition within five days of the first node being deployed.
In comparison to conventional seismic surveys of a similar size and complexity using cabled geophones, the client noted that the receiver deployment and retrieval crew size was more than 50% less on this nodal survey even though the receiver density was double that ofprevious surveys.
Access to high-resolution data, faster than ever before
The use of nodes reduced the need for line checks and eliminated technical downtime.
Previous cabled system operations required time-consuming troubleshooting every day in difficult terrain to deal with theft and damage to equipment. The customer noted that about two hours of productivity was gained each day using nodes rather than cables by avoiding technical downtime. This time saving contributed to significant improvements in productivity and accelerated delivery of the overall seismic programme.
High-resolution seismic data was therefore acquired over an area of 250 sqkm2 in just 28 days, allowing DNO to speed up the acquisition program and deliver processing-ready seismic data faster than ever experienced before. DNO received a fast-track 3D image ~four weeks after the final shot, and the fast-track results were of sufficient quality to start well planning immediately.
The per-channel cost of the STRYDE seismic system is at least half that of any other
seismic system in the world. Added to this, the operational efficiency and flexibility of
STRYDE’s nodal system mean that project cycle time can be reduced simultaneously with running a smaller crew with fewer vehicles and reduced logistics effort, all of which contribute to a significant reduction in the overall cost to acquire the survey.
As the oil and gas industry continues to seek reserves onshore to meet global energy
demands, operators require solutions that deliver quick and reliable subsurface insights at a lower price point. STRYDE’s Nodes™ are a clear example of how advances in technology are directly addressing industry challenges and needs, delivering efficient and highly effective seismic surveys for the growing onshore sector.