Gas Compositions - Permian Reservoirs in Central Kansas

Most Permian gases in central Kansas are low-BTU gases (i.e., <950 BTU/standard cubic foot). The main nonhydrocarbon component that causes the low heating value is nitrogen. The table below (from publications and unpublished sources) is a compilation of compositions and heating values for gas tested from Permian strata in central Kansas.

Click on the Above image for more detail, or download the data in this MS Excel file.

Mapping of the BTU data of Permian gases in central Kansas by a color code (see histogram at left) indicates that gas quality generally increases southeastward of the Ryersee Field. Nevertheless, low-BTU gases have been detected in Permian strata (mostly Chase Group) over large areas in central Kansas.

Heating value of Permian gases from central Kansas is inversely related to the percentage of non-hydrocarbon gases present. Percentages of nitrogen and helium can be derived from the BTU content of the gas and a predictable N:He ratio.