Publication Date:
2016-03-02
Description:
The Carboniferous Bowland Shale of northern England has drawn considerable attention because it has been estimated to have 1329 trillion cubic feet hydrocarbons in-place (gas and liquids) resource potential (Andrews 2013). Here we report on the oil and gas generation characteristics of three selected Bowland Shale whole-rock samples taken from cores and their respective kerogen concentrates. Compositional kinetics and phase properties of the primary and secondary fluids were calculated through the PhaseKinetics and GOR-Fit approaches and PVT modelling software. The three Bowland Shale samples contain immature, marine type II kerogen. Pyrolysate compositions imply primary generation of paraffinic–naphthenic–aromatic (PNA) oil with low contents of wax and sulphur. Bulk kinetic parameters have many similarities to those of productive American Palaeozoic marine shale plays. The secondary gas generation potential of Bowland Shale is greater than the primary gas potential although it requires a 10 kcal mol –1 higher activation energy to achieve peak production. Primary oil, primary gas and secondary gas reach their maximum generation at 137, 150 and 200°C respectively for a 3°C Ma –1 heating rate. Different driving forces of expulsion including the generation of hydrocarbon and overpressure caused by phase separation during sequential periods of subsidence and uplift could be inferred.
Print ISSN:
0016-7649
Topics:
Geosciences
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