Fugro Robertson’s portable rock properties analyzer, RoqSCAN™, recently completed field tests on Forest Oil Corporation’s Shannon Estate lease well in Crockett County, Texas.

Both a vertical pilot well and horizontal well were drilled successfully and key formations of the Permian Basin – from the Clearfork Formation to the Ellenburger Formation and focusing on the Wolfcamp Shale Formation – were sampled and analyzed.

The portable RoqSCAN system analyzes wellbore cuttings and core piece samples in high resolution and generates fully intuitive, highly quantitative mineralogical and textural datasets within one hour of cuttings being delivered to the RoqSCAN rig site unit. The data is captured and displayed in the form of a downhole log.

RoqSCAN is a collaborative effort between the first company to introduce automated and quantitative mineralogy to the oil and gas industry, Fugro Robertson; and the world’s first manufacturer of portable scanning electronic microscope (SEM) solutions, Carl Zeiss.

Fugro Robertson and Carl Zeiss collectively have 185 years of experience in relevant geosciences and optics disciplines. Fugro Robertson is celebrating its 50th anniversary in 2011 and is one of the leading geosciences/geological consultancy companies operating worldwide.

Fugro Robertson was also the first company to use cuttings data to assist with horizontal well steering when it launched its biosteering service in the early 1990s.

The rapid quantitative mineralogical analysis of drill cuttings at the wellsite offers a step change in the amount, type and quality of rock properties data to be used to support geologic-based drilling decisions, providing additional value to the operator. This technology is especially valuable in long lateral and horizontal wells in today’s shale plays where sequencing is a priority.

Historically, core samples and logs have been the method of choice for reservoir characterization. More recently, the analysis of drill cuttings (the drill bit-induced rock chips) have taken on a new importance, not only for reservoir characterization but also for directly determining the nature of the sequence through which the drill bit has penetrated.

After its introduction in April, RoqSCAN was immediately put to a 10-week field test for Forest Oil. Over the 10-week period, more than 600 samples were collected, analyzed and interpreted by RoqSCAN.

During the field test, Forest Oil drilled a vertical well and a long lateral pair targeting the Wolfcamp shale formation. The Wolfcamp shale formation spans vast parts of West Texas and southern New Mexico and is estimated to have gross oil reserves of 2.1 billion barrels oil equivalent. The Wolfcamp shale formation, so far, has been identified at depths of 5,000-to-15,000 feet, with a complex carbonate/mudstone lithology that can be 2,500-feet thick.

Additionally, during the drilling of the subsequent lateral well, cuttings data was collected every 10-30 feet. On many occasions – and because of a slower rate of penetration (ROP), RoqSCAN was generating mineralogical data 20 – 30 minutes faster than the measurement while drilling (MWD) tool over the same interval.

Finally, the real-time RoqFRAC™ curve analysis, designed to assist operators with mineralogical-based interpretation of these results, generated additional rock properties data on brittleness vs. ductility providing the Forest Oil team with additional mineralogical-based data to assess the fraccability over the entire length of the lateral target interval. The Forest Oil team will use this data to assist with tactical positioning of fraccing stages.

RoqFRAC provides information valuable to increasing fraccing efficiencies, thus providing both commercial and environmental benefits.

“The extensive field test has demonstrated that our RoqSCAN system has delivered value to our client, on site” said Dr. Guy Oliver, President of Fugro Robertson Inc. “The value is derived from highly quantitative rock properties data, generated at the wellsite and being made immediately available to the operating company for assistance in key decision making or, simply not having to wait two months for the samples to be analyzed in a laboratory.”

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