Patent ID: 8904858

Claim:
A method of measuring and correctly attributing fluid, geochemical and geomechanical properties to individual coal seams in a well penetrating multiple seams, comprising the steps of: (a) deploying a test string, comprising a straddle packer assembly at least one valve assembly and two pressure gauges positioned at different heights above the valve assembly, into a well on a work string; (b) positioning the straddle packer across a coal seam and setting the packers to isolate that coal seam from the remainder of the wellbore and other coal seams in the well; (c) opening a valve above the straddle packer assembly to allow fluid to flow from the coal seam into the work string; (d) monitoring of fluid flow rates and pressures at the coal seam during the flow period; (e) closing the valve above the straddle packer assembly and monitoring pressure at the coal seam during the build-up period; (f) filling the test string with water to surface, move the valve above the straddle packer assembly to the circulation position; (g) displacing the fluid in the work string under pressure to surface; (h) diverting the fluid through a choke manifold at surface applying sufficient back pressure to keep gasses dissolved in the fluid, while simultaneously monitoring fluid properties entering the choke manifold; (i) pumping air or nitrogen down the work string to lower the water level; (j) moving the valve above the straddle packer assembly back to the closed position before any nitrogen enters the annulus; and (k) continue withdrawing fluid from the coal seam into the work string above the straddle packer until the monitored fluid properties, including dissolved methane content, reach a steady state condition, where this condition indicates that the fluid is representative of authentic reservoir fluid in the coal seam.