Replies to This Discussion

Permalink Reply by Spring Branch,mineral owner on June 21, 2011 at 9:39

It would seem to be for pressure  "build up".  I suspect there is more to it than that.

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Permalink Reply by Bacon on June 21, 2011 at 10:47

Yep, I was wondering if 4 months wouldn't be considered a pretty long test period as well.  There was another well they shut in for a week while they fraced one in the next section which I found interesting from the standpoint that it could be affected from a mile away.

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Permalink Reply by Skip Peel - Mineral Consultant on June 21, 2011 at 10:55

During the frac operation, where possible, micro-seismic monitors are used in nearby wells to monitor the propagation of the fracture network created by each frac stage.  This may account for the well you mention being temporarily shut in.

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Permalink Reply by Bacon on June 21, 2011 at 11:08

Excellent point.

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Permalink Reply by Les Bamburg on June 21, 2011 at 13:28

Bacon, it has been common in all shale gas plays to temporarily shut-in nearby wells during fracture stimulation operations.

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Permalink Reply by Les Bamburg on June 21, 2011 at 13:26

Bacon, a "Build-Up Test" is a technique utilized to assess well drainage areas and permeability.  The low permeability of the Haynesville Shale would likely account for the required length of the build-up test period.

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Permalink Reply by Sylvester Deal on June 21, 2011 at 13:38

Bacon,

The schedule you post looks more like a well deliverability test.  Some restrictions apply, such as long shut-ins between flow periods and starting from a shut-in condition.  I don't know the practices or requirements for LA & TX in Haynesville, it could be something different, possibly research to give the engineers a better handle on projecting performance.  Since conventional test and analyses seldom apply to tight and unconventional formations, the standard now is decline curve analysis to project a well's future performance and ultimate recovery for Security and Exchange Commission reporting requirements for reserves.  Decline curve analysis is curve fitting the past performance to predict the future.  Before Arps, calculators, and computers this was done with a french curve.

A pressure buildup test is used to determine reservoir rock properties, fracture properties, and reservoir pressure.  In shales, only fracture properties and an estimated reservoir pressures would be derived from this test as the test length can run into months, even a year, to calculate rock properties.  The production rate before the test must be steady and shut-in pressures must be recorded throughout the test for proper analysis.  The test described doesn't fit the needs for a buildup test.  Where any frac jobs run nearby during these shut-ins?  Any other shut-ins after Feb 2011?

 

SD

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