The future of exploration

To sum up the current status of exploration technology, this line from a pop song captures it perfectly. The world is waking up from a history of too little computing power and imprecise measurements and is sampling the morning aroma of exciting new approaches to finding buried treasure.

It seems that purveyors of exploration technology are in the right place at the right time. They’re the beneficiaries of tremendous strides being made in the computing, telecommunications and gaming industries, and sustained soaring commodity prices are pushing the demand for their services to new heights.

Methodologies that seemed like a good idea if anyone was willing to pay for them back in the ’90s are now surging forward to become mainstays in the exploration toolkit.

But more work is needed. Exploration technology is not going to be the silver bullet that

Deepwater nodes can be used instead of ocean-bottom cables in multicomponent seismic acquisition. (Photo courtesy of Fairfield Industries)

returns the world to cheap, abundant sources of oil and gas; in fact, its increasing sophistication is the result of a necessity to identify and image increasingly complex targets. But there is potential for some very significant improvements.

The National Petroleum Council published a report earlier this year titled “Facing the Hard Truths about Energy: A Comprehensive View to 2030 of Global Oil and Natural Gas,” which focuses on the challenges the world will face over the coming years regarding the global energy future. The study took 18 months and involved more than 350 experts from diverse backgrounds, many from outside the energy industry.

The Exploration Technology subgroup worked to identify advances that could improve the effectiveness of current techniques.

“Despite the substantial improvements in exploration technology and reduction in deployment costs since the 1970s, oil and gas explorers have not maintained the high

	CSEM sensors await deployment in a ship’s hold. (Photo courtesy of Offshore Hydrocarbon Mapping Ltd.)

discovery volumes of that earlier period,” the study notes. “This decrease came despite the increased amount of 3-D seismic surveys being shot over the period. Several authors concluded that improved exploration and exploitation technology has prevented a more drastic decline in discovery volumes.”

The big five
This study, released earlier in 2007, outlines five key exploration technologies “in which future developments have the potential to significantly improve exploration results over the next 25 years”:
• Seismic technology. The report states that high- and ultra high-density acquisition technologies have great potential. Rapid data processing can improve resolution of complex subsalt, deep or subtle geologic features.
• Controlled-source electromagnetics (CSEM). Using the same basic technology as a resistivity logging tool, CSEM surveys find subsurface hydrocarbons through the resistivity contrast they provide.
• Interpretation technology. Two key advances here would be in better integration of geophysical and geologic data to develop quantitative interpretations and the development of seismic “search engines” to interrogate increasing data volumes.
• Earth-systems modeling. While many explorationists recognize the benefits of basin modeling, again it’s a volume issue that requires massive compute power to simulate depositional and diagenetic systems. “Advances in modeling more integrated earth systems along with capturing uncertainties in potential scenarios and parameters could significantly help explorationists identify new plays and sweet spots,” the study notes.
• Subsurface measurements. This relates to measuring subsurface properties such as fluid type, porosity, permeability, temperature, etc. “Advances in sensor types, durability, sensitivity and deployment could improve exploration programs significantly by identifying both penetrated and bypassed pay.”

In addition to identifying technological advances, the study group also pinpointed unconventional resources as “a special category in the early stages of understanding” to

An ION FireFly geophone is teamed with a Trimble navigation system. FireFly is one of the new generation of cableless land acquisition systems. (Photo courtesy of ION)

which many of these core technologies could be applied. Two major advances would help move this area forward: improved measurement capabilities and predictive geologic modeling of hydrocarbon distribution and deliverability, and improvements in techniques that
could help identify sweet spots.

Auxiliary technologies were identified that have additional potential to improve exploration results:
• Drilling technology improvements that could improve the ability to tap new environments and encourage more exploration drilling of higher risk new play types;
• Nanotechnology for increased sensor sensitivity, improved drilling materials and more powerful computing; and
• Computational technology improvements in speed, memory and cost, which will impact data acquisition, processing and interpretation.

Near-term technologies
The study group identified significant technologies that are likely to be perfected by 2010. The first is high-density seismic data and rapid data processing. This results in greater signal-to-noise ratio, which leads to better resolution and thus better reservoir understanding. For this to become commonplace, substantial improvements in processing methods are needed.

Second is subsalt imaging. The industry has already made tremendous strides in imaging below salt, and the study concludes that continued improvements will likely lead to more subsalt discoveries.

Next is CSEM. While this technology is developing rapidly, it still sometimes offers up false positives from hydrates or volcanics. Faster 3-D modeling and inversion capability will help in this discrimination.

Finally, the integration of CSEM with structural information from seismic data will be an important approach to increase the resolution of information obtained via CSEM methods.

Farther out
The study group also identified technologies that will take longer to reach commercialization, but which have the potential to significantly impact exploration success in the future. The two technologies that were deemed to have the highest significance both revolved around CSEM.
One is the ability to use the technique in shallower water. The shallowwater environment is noisier than deep water, and substantial advances will be needed to enable robust signal acquisition and analysis.

Onshore CSEM is also rated as highly significant, and its current difficulties are the same as those in shallower water.

Rating a high-to-medium level of significance were three additional technologies: ultra high-density data and processing, deep-reading CSEM, and the development of the aforementioned seismic “search engine.” Of the last, the study states, “This type of technology would take advantage of advances in computational power, pattern-recognition technology, geophysical data and geological concepts in a highly automated fashion.”

Finally, the study rates seismic wave theory research as “potential high impact but with attendant high risk.” “Basic research into wave theory is a continuing effort in both industry and academia,” the report states. “Synergistic collaborations between the two have led to gradual improvements in processing and could result in large leaps forward. For example, it should enable more accurate quantitative modeling of key seismic data.” The “attendant high risk” is that the large leaps might not occur.

Recent advances
One of the interesting aspects of exploration technology is the speed at which new ideas are being adopted. While some technologies like multicomponent seismic are still not commonplace after several years of discussion, others, such as wide- and multi-azimuth streamer surveys and CSEM, seem to have come out of nowhere and are nearing routine usage. Time-lapse seismic is so commonly used in parts of the world that it doesn’t even register as “new” technology anymore.

More recent developments are also gaining acceptance. The move to wireless and cableless land systems is underway, and several systems are on the market. Many of these also operate as passive seismic systems, measuring natural sounds rather than requiring a source. Offshore, several companies offer nodal systems that can be deployed on the ocean floor, left in place for several days or weeks, then recovered with an ROV for data download.
Harder-to-find targets will continue to drive the need for increasing sophistication in exploration technology, but computers will get faster, components will get smaller, algorithms will get better, and the oil and gas industry will be up to the challenge.