School of Earth and Environment
Turbidites Research Group

Autogenic versus allogenic controls on deep-sea channel evolution

This fully-funded PhD is to be run under the auspices of the Turbidites Research Group within the School of Earth and Environment. This 3.5 years funded award will include tuition fees (£4,250 for 2017/18) and stipend (£14,553 for 2017/18) with a CASE award stipend enhancement of £1,000pa.

Supervisors: Professor Bill McCaffrey, Dr Marco Patacci, Dr Luca Colombera, Dr Rob Dorrell

Application deadline: 8 June 2017

PhD Start Date: September or October 2017

Summary. Submarine channels are the earth's largest and most important conduits for sediment transport. They comprise an important component of the largest sedimentary accumulations: submarine fans. On the modern sea floor and in the ancient rock record, submarine channels are seen to form in complex patterns, sometimes progressively shifting their position with time, sometimes abruptly shifting to new locations through channel avulsions. The key goal of this project is to assess the relative roles of internal (autogenic) vs. external (allogenic) forcing in the development of individual submarine channels and of submarine channel networks.

As well as developing fundamental new understanding, the work will also find practical application by enabling prediction and characterisation of channelised architectures based on prior knowledge of their boundary conditions of formation and/or their geometrical configuration. The project will exploit large dataset analysis to better understand submarine architecture development, based upon a combination of prior submarine channel studies and original data (field and/or seismic data). Links to the wider experimental and numerical modelling research programme of the TRG are possible; the programme is designed to be flexible, and can be adapted to the particular interests of the student.

Aim and objectives. The aim of this project is to develop a series of depositional models for submarine channels that account for the range of external and internal controls responsible for the observed range of sedimentary architectures. The research will involve development and employment of the Deep-Marine Architecture Knowledge Store (DMAKS), a relational database designed and populated by members of TRG at Leeds. Collected data will be used to address research questions (directly as part of this project; see below), but also more widely within the research group to inform modelling of hydrocarbon reservoirs and process-based experimental and numerical modelling of submarine channels. Both fundamental and applied research themes can be investigated as part of the project, and these may include, but are not limited to, any of the following topics and related research questions.

  • Determination of the signature of geological controls on the sedimentary architecture of submarine channel fills. How can channel geometry (planform and cross-sectional) and fill characteristics be used to evaluate the role of known external controls (e.g., sea level, climate, tectonics, latitude, grainsize and composition) on system development? What type of information can be extracted from the analysis of channel planform to inform us about their external controls? To what degree do the relative roles of autogenic vs allogenic controls in channel geometry and fill change along channel length? What geological boundary conditions determine the largest variance in channel-fill geometries and style of infill, and are therefore most useful for categorising facies models and guiding subsurface interpretations and predictions?
  • Investigation of relationships between modern landforms and ancient deposits. What are the relationships between styles of morphodynamic evolution (e.g., aggradation, lateral migration) of modern submarine channels and resulting characteristics of infill and stacking patterns of channel bodies recognized in the rock record? To what extent does the hierarchical organization of sedimentary deposits relate to hierarchy in drainage patterns? What types of scaling relationships do we see in modern environments and between sub-environments that might be applicable in context of hydrocarbon exploration?
  • Improved application of analogue data in subsurface studies. Can emergent relationships within large datasets improve the algorithms currently used to model channelized deep-marine successions in the subsurface? How can we best use the inherent hierarchical organization of sedimentary deposits forming channel bodies in reservoir-modelling workflows? What geological factors shall we consider for selecting analogues to channelized subsurface successions?
Aerial photo of the submarine channels of the Gorgoglione Flysch and the village of Pietrapertosa, Southern Italy. (Credit: Claudio Casciano, TRG PhD student).
Aerial photo of the submarine channels of the Gorgoglione Flysch and the village of Pietrapertosa, Southern Italy. (Credit: Claudio Casciano, TRG PhD student).

Methodology. Two main methodologies will be employed to fulfil the aim of this project and to answer the stated research questions:

  1. Compiling literature data from modern submarine channels and ancient channel fills and recording the associated external controls by populating DMAKS - a database storing aspects of deep-water stratigraphic architecture developed in-house by TRG at Leeds. This will involve evaluating hierarchy of channel elements and integrating high-resolution modern bathymetries and 3D seismic volumes with outcrop-derived studies.
  2. Fieldwork to examine the architectural complexity and larger-scale spatial heterogeneity of submarine channel deposits accumulated in a range of settings, and to examine the stratigraphic evolution of such systems over time. The choice of study area is open, but identified candidate field areas include the Spanish Pyrenees, the Italian Apennines or the French Alps. These successions are exceptionally well-exposed such that they provide excellent opportunity for field-based study to examine and document architectural heterogeneity and stratigraphic evolution.

Eligibility. Applicants should have a BSc degree (or equivalent) in geology, earth sciences, geophysics or a similar discipline. An MSc or MGeol in applied geoscience or petroleum geoscience (or similar) would be an advantage. Skills in field-based geological data collection and field sedimentology and stratigraphy are desirable. Experience of using GIS software would be useful, though is not essential. UK and EU students are welcome to apply for this project; any changes in EU student fees will be underwritten by the TRG.

Training. The successful applicant will work within the inter-disciplinary Turbidites Research Group, which is part of the wider Sedimentology Group at the School of Earth and Environment, University of Leeds. The TRG has a number of on-going research projects related to deep-marine clastic sedimentology via field studies, physical and numerical modelling and seismic studies. The project will provide specialist scientific training, as appropriate, in: (i) field-based techniques for the sedimentological and architectural analysis of clastic successions; (ii) geological interpretation of seismic datasets; (iii) relational-database theory and practice; (iv) statistical analysis. The mixed pure- and applied-science nature of this research project will enable the student to consider a future career in either academia or industry. In addition, the student will have access to a broad spectrum of training workshops provided by the Faculty that include an extensive range of training workshops in statistics, through to managing your degree, to preparing for your viva. The successful candidate will be strongly encouraged and supported to publish the outcomes of their research in leading international journals.

The project will be run as a CASE award, supported by geological software house PDS; as well as a £1k pa stipend enhancement, there will also be opportunities for the appointed applicant to undertaken an internship with PDS. Such placements will involve working embedded in a team of applied geology professionals.

Further Information

For more information about this project and other TRG activities contact:

Bill McCaffrey, w.d.mccaffrey(at)leeds.ac.uk, http://trg.leeds.ac.uk/