Petroleum Geochemistry Division – Other Services...

GEOTECH provides a range of other geochemical services which can be tailored to fulfill the requirements of our industry clients. These include:

Head Space Gas Analysis

Canned cuttings can be submitted for headspace gas analysis. Gas maturity and gas and gasoline concentrations relative to TOC contents can be determined. The technique allows for the location of zones of hydrocarbon generation and out-of-place gas to be identified. Headspace gas data can be used to plot both lateral and vertical intervals of oils and gas proneness.

Thermal Extraction GC-MS

A crushed sediment sample is heated and the free hydrocarbons analysed by GC-MS. This analysis can provide useful information regarding the location of oil / water contacts and effects of water washing over a zone of interest. Thermal extract GC-MS has the advantage over solvent extraction / whole extract GC-MS in that gasoline range hydrocarbons (which are usually removed during solvent extraction) can also be analysed.

C7 Temperature of Expulsion

This technique allows the hydrocarbon expulsion temperatures to be determined for use in basin modeling packages.

Seal Capacity Studies

Seal capacity studies have traditionally been performed using petrophysical techniques. Standard geochemical tests such as Rock-Eval pyrolysis, solvent extraction and GC, however, are excellent low cost, fast ways to determine the presence of free hydrocarbons in a seal.

Interpretation of these data by experienced geochemists allows accurate assessments of seal capacity and character, in particular, whether hydrocarbons from an underlying reservoir have penetrated an overlaying shale layer which could be a potential seal.

Water Analysis

GEOTECH offers a wide range of routine and specialised water analyses for the determination of both standard and non-standard components in water samples.

Hydrous Pyrolysis

A solvent extracted sediment sample is heated in the presence of water in order to artificially generate gaseous and liquid hydrocarbons. Generated hydrocarbons are subsequently analysed by GC-MS and a gas / oil ratio is determined. One benefit of this technique is that data are not influenced by migrated hydrocarbons or drilling additives.

TAI/SCI

The Thermal Alteration Index and Spore Colour Index can be used in conjunction with techniques such as vitrinite reflectance determination as kerogen maturation parameters.