Wavrek, David A.¹, Dennis Coleman², Steve Pelphrey², Don Hall³, Mark Tobey⁴, Daniel M. Jarvie⁴ 
(1) Petroleum Systems International, Inc, Salt Lake City, UT 
(2) Isotech Laboratories, Inc, Champaign,
(3) Fluid Inclusion Technologies, Inc, Broken Arrow, OK
(4) Humble Instruments & Services, Inc, Humble, 

ABSTRACT: Got Gas? Innovative Technologies for Evaluating Complex Reservoir Zones

A series of analytical tools are uniquely combined to provide new insight to key questions surrounding gas and gas-condensate reservoir system evaluation and development. The key to this application has been advances in hydrocarbon detection limits in the gas phase. The samples are initially high-graded for signal type using results of hydrocarbon-bearing fluid inclusion analysis. The specific intervals of interest are then analyzed by different analytical tracts that focus on the gas vs. liquid phases. The hydrocarbon gas phase analysis includes isotopic composition of the individual molecules (e.g., methane, ethane, propane). The liquid fraction (analogous to gas separator fraction) is isolated with a special cryogenic extraction system to provide a fraction suitable for conventional analysis. Novel interpretation schemes, however, need to be applied to molecules with advanced thermal stability (e.g., adamantoids) and/or are by-products of gas generation mechanisms. Applications of this cost-effective technology include isolation of reservoir zones with different GOR's and/or enhanced with dilutants (CO₂, H₂S, N₂, etc); provide pay allocation by comparison with produced gas; allow gas-source rock correlations; and delineate of reservoir compartments and seals.

AAPG Search and Discovery Article #90026©2004 AAPG Annual Meeting, Dallas, Texas, April 18-21, 2004.