Structural and kinematic analysis of the Slyne and Erris Basins: understanding the link between structural evolution and traps
PhD Candidate: Conor O’Sullivan
Supervisor: Dr. Conrad Childs, Dr. Muhammad Mudasar Saqab & Prof. John Walsh
Funded by: This research is supported in part by a research grant from Science Foundation Ireland (SFI) under Grant Number 13/RC/2092 and is co-funded under the European Regional Development Fund and by PIPCO RSG and its members companies.
Abstract:
The Slyne and Erris basins are narrow, elongate, approximately co-linear NNE trending basins that lie on the continental shelf 50 to 100 km offshore NW Ireland. The basins formed during the Permo-Triassic to Cretaceous in response to WNW-ESE directed extension during the continental rifting process that ultimately led to Late Cretaceous Atlantic opening. They are part of a system of basins that stretches from the West of Shetland basins to the Porcupine basin and they preserve Permo-Triassic and Jurassic successions, with variable amounts of Cretaceous and Cenozoic strata. A pronounced angular unconformity placing Cretaceous to Cenozoic sequences (containing evidence of several phases of uplift/erosion) on Jurassic and older rocks indicates significant uplift and erosion which has removed much of the Jurassic section from these basins. These basins are underexplored but discoveries like the Corrib gas field and the Bandon oil discovery demonstrate the presence of a working petroleum system. This project aims to develop a robust structural framework for the Slyne and Erris basins, including a detailed timeline of the formation and development of these basins. Through detailed seismic mapping and integration of existing borehole data this project aims to understand the location and nature of transfer zones between sub-basins, the origin and nature of structures occurring in the hanging walls adjacent to major basin-bounding faults, shown to be effective hydrocarbon traps, and the influence of salt layers on the development of these basins. This knowledge will be used to understand the timing of trap formation and fault reactivation relative to periods of hydrocarbon generation, and to consider the impact of fault reactivation on the integrity of the various trap structures found in the Slyne and Erris basins.
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