Some have called the Barnett Shale the new Austin Chalk, while others draw parallels with coalbed methane. In each case, new technologies are making what used to be an uneconomic venture a highly profitable one. Further, the technologies can be learned at a distance. Shale gas is now being produced from the Barnett Shale and the Fayetteville Shale, while companies are starting to drill and produce gas from the Caney Shale. In other parts of the country, the Antrim and the New Albany shales are of interest.
The technologies include new methods of processing well-log data. These new computing techniques take well logs that contain information on the rock characteristics and reprocess them using new algorithms. The analysis can reveal overlooked reserves, or possible extensions to existing fields. One such program is called Geologic Analysis via Maximum Likelihood System (GAMLS), and it is available through Eric Geoscience.
GAMLS is a software program which allows geologists, geophysicists, engineers, and petrophycists to evaluate old fields, look for step-outs, and to analyze the potential of new producing zones. In many cases, the new zones have been overlooked because technologies to determine the zone's potential, and then to successfully drill and complete a well in the the hydrocarbon-bearing formation, did not exist.
Such a situation was often the case with tight gas and shale gas, including the Barnett Shale and Fayetteville Shale, where permeability was measured in the milli-darcies. Technological advancements have led to the ability to economically produce shale gas, but it is very important to understand the lithology and petrophysical characteristics of the formations, as well as to be able to detect the presence of commercially viable quantities of hydrocarbons. Perhaps one of the most cost-effective ways to explore for shale gas within an existing field is to utilize programs such as GAMLS to do the following analytical tasks (from the website):
- Analyze digitized wireline well log data, plus core data if it exists.
- Cluster datasets into modes (= clusters = rock types = flow units) using a model-based, maximum likelihood system wherein each sample is assigned to each mode with a fractional probability (mode probability assignment). Therefore, samples (depths) assigned to the same cluster have similar log properties.
- Permit correlation of rock units between wells.
- Generate graphics (plots) and tables that show the relationships among variables for each mode.
- Permit predictions of missing data using the statistical relationships computed during a previous clustering run.
These are just a few of the new ways to use e-learning to develop skills that directly lead to positive economic results.
Fayetteville Shale - February 2006 - AAPG Explorer -
Barnett Shale - February 2006 - AAPG Explorer --
Other shales -- Woodford shale gas / Coalbed methane -
PTTC Network News - 2004
Oklahoma Geological Survey - 2006
2006 Gas Shales Modeling --
Petroquest -- Woodford Shale test -- 2005 financial results
Petroquest Financial Information -- Lafayette, LA