How Halliburton Does It

Addressing delegates at the Tight and Shale Gas Summit in Budapest, Hungary, Peter Smith, Product Manager at Easywell-Halliburton spoke about Well Design and Construction: The latest Practices and Developments for tight and shale gas.

He said he wanted to provide some hints at what Halliburton had learned at the North American shale plays, commenting: “We believe there can be some lessons learned in other parts of the world.”

Mr. Smith talked about the “shales” that were involved in extracting natural gas.

“When we’re talking about shale or rock, it’s a lot about the particle size. You can get many different types of rock in a shale,” he explained. “There’s no such things as a shale being a shale; there are many different types, and it’s a complicated type of rock.”

His slide showed the lowest permeabilities to the highest, from conventional gas to complex, tight gas to shale gas and to coal bed methane. He also showed where shale oil fit into that.

Another slide showed the geographical spread of reservoirs in North America, noting that “23% of natural gas production [came] from shales”.

“What has facilitated this?” asked Smith. “It’s primarily due to advances in technologies and the ability to drill horizontal wells.”

Showing a rig count increase, he said it had to do with horizontal rig counts, which he said had increased greatly since the beginning of the new millennium.

In reference to tight gas versus shale source reservoirs, he said: “Stage placement is important for both of them, which are different in terms of the drivers for them.”

He stressed that it took time for a molecule of gas to make it through a rock.

In terms of lessons learned, he said it had been 33 years since the Barnett had started to be explored. “We see a decreasing time scale with a knowledge and technology increase. We’ve learned a lot about where to drill and map out the reservoirs. It’s more about the drilling process and how to turn that well more efficiently through fracturing technology,” said Smith.

He listed Halliburton’s steps: 1) quantify, 2) drill and complete, and 3) analyze.

The first phase involved basin modelling, geophysics, etc.; then stimulation design or advanced well planning. Smith explained: “After you’ve done all that you can go through some production history matching ending up with a fully integrated asset model.”

In terms of petroleum systems, he said the following were the drivers: maximize stimulation potential, isolate the unique attributes of each shale, and determine critical reservoir attributes.

Getting one’s well in the right orientation was crucial, he said, adding that all the parts came together in some sort of model. He showed a workflow of shale field development, highlighting the specifics on the challenges for shale plays. 

“When we look at the productivity side,” said Smith, “you have to understand  the orientation of the stresses of the rock. It’s really understanding the reservoir and the rock structure itself. In the drilling phase you may find that you have to go through sandstone or reactive shales, which cause a high percentage of the problems.”

He said everything needed to be considered in a holistic way, taking into consideration critical factors and key elements.

“Our experience is that you do need to take a holistic approach around stimulation and completion. The completions themselves should be designed to maximize reservoir contact. You have to really understand what it is that you’re drilling through and what you’re trying to produce,” he concluded.

Smith added: “We’re here to help and that’s what our job is.”