Offshore Tech Evolves for Deeper Waters, Deeper Reservoirs

Abstract

_ Since the late 1930s, the offshore industry has moved from installing the first offshore platform in 14 ft of water to the ultradeepwater 20K era. Advances in seismic, drilling, and development technologies all helped move the industry from shallow waters to ultradeepwaters, from lower-pressure reservoirs to high-pressure/high-temperature (HP/HT) reservoirs, and beyond known hydrocarbon areas like the Gulf of Mexico (GOM) into frontier regions, like Guyana. Brent Gros, vice president of Chevron’s GOM business unit, told JPT there is a stark difference between the GOM of today and how it was when he first started working in the area 26 years ago. Now, he said, operating further from land in water depths of 4,000 to 7,000 ft is the norm. “We’re not really taking crew boats to those platforms, given the distance from shore. We operate as well at much higher pressures,” he said. Jayme Meier, ExxonMobil’s vice president of deepwater project delivery, echoed that sentiment. At the dawn of the offshore era, “anything that was in any amount of water was, by definition, deep water, because it was as far as you could go,” she told JPT. “And we are now at the stage where we are routinely doing things that are in 2000 m (6,560 ft) of water or more, and we continue to press boundaries and technical limits to be able to move further out in water depth.” As such, she said, the fundamental definition of deep water has shifted in the past quarter century. Where To Drill? “To find oil and gas resources, we rely on seismic, and we’ve seen huge advancements in seismic over the past 25 years,” Gros said. 3D seismic technology, pioneered half a century ago, sharpened the view into the world’s reservoirs, and new seismic processing methods have helped identify new opportunities. “Now we have ocean-bottom node surveys, which essentially take a lot of the noise out of surveys, allowing us to image deeper with a clearer image. We also have four-dimensional seismic, which helps us understand the performance of reservoirs through time,” he said. “If you compare the seismic capability today to what we had in the past, it’s like seeing the world with a new pair of glasses, and it really helps us understand potential prospects in a more-complex geological setting and pursue those opportunities in deeper water and deeper horizons than we previously would have been able to.” Deepwater Challenges Moving into ever deeper waters requires more tech and more-capable drilling rigs. It also requires precision, Meier noted. “Technology allows us to position a floating rig on the surface of the ocean. It’s got to be able to drill at very precise angles and precise locations, and significant extensions of technology were needed to enable that to happen. We’re at the point now where we’re even doing multizone completions on our wells in deep water,” she said. point now where we’re even doing multizone completions on our wells in deep water,” she said. She called deepwater “by far the most exciting space” to work in. It requires planning and designing for facilities that must withstand intense, harsh, and constantly changing conditions throughout its lifetime.