Triassic fluvial successions form important primary and secondary reservoirs in the Central North Sea (CNS) and contain significant future exploration potential. Extraction of hydrocarbons from these deposits is hampered by a lack of knowledge regarding reservoir architecture, geometry, connectivity and internal heterogeneity. Recent work suggests that Triassic fluvial reservoirs in the CNS comprise a series of overlapping point-sourced distributive fluvial systems (DFS) that interact with an axial system. DFS and axial systems show predictable downstream changes in channel size and depth that are reflected in sandstone body size, architecture, geometry and connectivity (e.g. Owen et al. 2015, 2017). Using relationships established from present day and outcrop examples and calibrated against core and wireline log data, it is possible to construct a suite of reservoir models using a range of different geometries that characterise the behaviour of the Triassic reservoir units.
To characterise the behaviour of different Triassic reservoir intervals the PhD student will build a series of synthetic models that represent the stratigraphy for the different parts of the DFS and axial systems considered to be present within the reservoir intervals of Quads 22, 29 and 30. The aim of this fully funded project is to quantify the role of stratigraphic complexity on reservoir production characteristics (e.g. Gray et al. 2019). The student will analyse in house outcrop datasets available at the University of Aberdeen to establish likely sediment body geometries, grain size and heterogeneity distribution within appropriate proximal, medial and distal sections of DFS deposits and axial fluvial systems. Particular attention will be focussed on establishing appropriate analogues. Comparison of reservoir model builds with production data from Triassic fields will be used to calibrate and test the reservoir models. Models will be dynamically tested using a range of typical fluid and PVT properties from the area. The models will be focused on stratigraphic architecture but they will also provide information on the role of the stratigraphic heterogeneity in controlling production.
This PhD study will provide an excellent opportunity for a student to gain expertise in a wide range of different techniques and transferrable skill sets that can be utilised in a future geoscience-based career.
Selection will be made on the basis of academic merit. The successful candidate should have, or expect to obtain, a UK Honours degree at 2.1 or above (or equivalent) in Geology or a related discipline.
It is essential that the successful candidate has experience of the collection and interpretation of sedimentological data, familiarity with manipulation and interpretation of subsurface datasets.
Formal applications can be completed online: https://www.abdn.ac.uk/pgap/login.php
• Apply for the Degree of Doctor of Philosophy in Geology
• State the name of the lead supervisor as the Name of Proposed Supervisor
• State the exact project title on the application form
When applying please ensure all required documents are attached:
1. All degree certificates and transcripts (Undergraduate AND Postgraduate MSc-officially translated into English where necessary)
2. 2 Academic Reference (on official headed paper and signed or emailed directly to us from referees official email address)
3. Detailed CV
The start date of the project is October 2020.
Gray et al. 2019 The influence of stratigraphy and facies distribution on reservoir quality and production performance in the Triassic Skagerrak Formation of the UK and Norwegian Central North Sea. Geological Society, London, Special Publications 494
Owen et al 2015. Quantification of a distributive fluvial system; The salt Wash DFS of the Morrison Formation, SW USA, Journal of Sedimentary Research, 85, 544-561.
Owen, et al. 2017. Vertical trends within the prograding Salt Wash distributive fluvial system, SW United States. Basin Research 1–17, doi: 10.1111/bre.12165.