Flow transformations and bedform development against intrabasinal slopes: integrating physical experiments and outcrops

Supervisors: Hodgson, D.M.1, Peakall, J.1, Kane, I.A.2, Flint, S.S.2, Jackson, C.3, Schwarz, E.4

  1. 1 Stratigraphy Group, School of Earth and Environment, University of Leeds, Leeds LS29JT, UK
  2. 2 School of Earth an Environmental Sciences, University of Manchester, Manchester M13 9PL, UK
  3. 3 Basins Research Group (BRG), Department of Earth Science & Engineering, Imperial College, Prince Consort Road, London, SW7 2BP, UK
  4. 4 Centro de Investigaciones Geológicas (CIG), La Plata, Provincia de Buenos Aires, Argentina

The depositional architecture of submarine lobe deposits is well constrained from unconfined basin-floor settings. In contrast, the range of facies and bedforms present where lobes abruptly pinchout against intrabasinal slopes is less well understood. However, this style of pinchout is commonly imaged in seismic reflection data where it can lead to high risk stratigraphic trap plays in mature (e.g. North Sea) and frontier (e.g. Wilcox Group, GoM) hydrocarbon basins. Through integration of outcrop and subsurface analogues with the results of physical models, risks associated with low resolution imaging of basin-floor stratigraphic and combination traps can be reduced. An improved understanding of the processes and products associated with the interaction of sediment gravity flows with topography are key to predicting, for example, the rate of thinning and the changes in sedimentary facies (and hence reservoir quality) towards pinchout, and the spatial extent of 'waste zones'.

To improve our understanding of sediment gravity flow behaviour above different slope configurations, this PhD studentship will utilise a physical modelling approach in the Sorby Environmental Fluid Dynamics Laboratory, University of Leeds. The experiments will be designed to investigate key parameters, such as the gradient and shape of the confining slope, and the angle of incidence between the flow and the slope. Additional experiments will investigate the effect of changing flow concentration on the height and trajectory of flows as they interact with topography. Individual flows and their deposits can be monitored and sampled to assess the interplay of these variables. There is scope for candidates with relevant skills and interests to pursue numerical modelling (CFD or rules-based) approaches to understand flow interactions and lobe stacking patterns.

In parallel, the depositional architecture of natural systems preserved in the rock record will be investigated. You will therefore study deep-water deposits in the Early Jurassic Los Molles Formation, Neuquén Basin, Argentina, where lobe and lobe complexes, which pinchout against intrabasinal relief, are superbly exposed successions. The Neuquén Basin outcrops offers a rare opportunity to study an exhumed stepped slope system deposited within a series of linked depocentres during the syn- to post-rift transition. Of particular interest is the number of dip-oriented sections through onlaps, which remain poorly documented in exhumed examples. Fieldwork will focus on the development of detailed facies and architectural panels, which can be used to generate seismic forward models of lobe complex terminations. Integration of outcrop-derived rates and styles of facies change (sandstone proportion, amalgamation ratio, etc.) with results of individual flows from physical modelling experiments will help constrain the sub-seismic 3D architecture of stratigraphic traps.

This studentship is focused on a topic of international importance and will form part of the Lobe3 project, which is an industry-funded research programme. We expect you to submit manuscripts to international scientific journals during the course of your studentship, and to present your results of their research at relevant national and International conferences. The project will provide you excellent training in physical modeling, fieldwork, process sedimentology, experimental sedimentology, data analysis, and the development of geological models. You will join one of the largest groups in the world working on earth surface processes and sedimentary basins, having access to state-of-the-art facilities and the support of supervisors with leading expertise in process sedimentology and the physical modelling of deep-marine sedimentary processes and systems.

Application deadline is 25th March, and interviews will be held on 16th April in Leeds, UK. For more information on this studentship please contact Prof David Hodgson (d.hodgson@leeds.ac.uk; +44 113 343 0236) and complete the online application form indicating the project title and primary supervisor at: http://www.see.leeds.ac.uk/admissions-and-study/research-degrees/iag/three-fully-funded-phds-as-part-of-the-lobe3-joint-industry-programme/

posted: 26 February 2018     Please mention EARTHWORKS when responding to this advertisement.