Hybrid event beds in confined basins

PGR-P-1304

Key facts

Type of research degree: PhD
Application deadline: Ongoing deadline
Project start date: Saturday 1 October 2022
Country eligibility: UK only
Funding: Funded
Source of funding: External organisation
Supervisors: Professor David Hodgson and Dr Adam McArthur
Additional supervisors: Dr. Lawrence Amy (UCD), Dr. Mattia Marini (Milan), Dr. Marco Patacci
Schools: School of Earth and Environment

<h2 class="heading hide-accessible">Summary</h2>

Hybrid event beds in confined basins Supervisors: Dr. Adam McArthur (Leeds), Dr. Lawrence Amy (UCD), Prof. David Hodgson (Leeds), Dr. Mattia Marini (Milan), Dr. Marco Patacci (Leeds) A PhD studentship to be run under the auspices of the Turbidites Research Group (TRG) in the School of Earth and Environment at the University of Leeds Start date: October 2022 Highlights: • Opportunity to undertake field, laboratory and subsurface investigation of stunning datasets from France, and the subsurface of the Gulf of Mexico. • Join an integrated research group, with links to international researchers and industry. • Attend international conferences in Europe, the US and elsewhere. • Project sits alongside linked research as part of a larger research programme. • Opportunities for career development (academia, internships, industry and beyond). The depositional record of longitudinal transformations of particulate gravity flows, hybrid event beds, is one of the major recent advances in deep-water sedimentology. Their formation, bed properties, and distribution in relatively unconfined settings are now well understood. However, their occurrence in confined basins is less well documented. The primary objective of this project is to examine the stratigraphic occurrence of hybrid event beds in confined deep-marine basins, to understand how their occurrence relates to the evolution of both the flows and the basin topography. This project will help develop our fundamental understanding of how deep-water sedimentary processes respond to confinement. The project will also help develop an applied understanding of the fill and rock properties of hybrid beds in confined basins, which are hosts of conventional resources, sinks of organic carbon, and potential hosts of man-made pollutants. This project will benefit from field studies in the famous Peïra Cava Basin, SE France; decades of prior studies by the wider research team provide a rigorous stratigraphic framework for the study. Additionally the study may exploit subsurface data of confined basin-fills from the Gulf of Mexico, including seismic, well, and core data, to characterise the occurrence of hybrid beds in subsurface architecture.

<h2 class="heading hide-accessible">Full description</h2>

Rationale: The depositional record of longitudinal transformations of particulate gravity flows, hybrid event beds, is one of the major recent advances in deep-water sedimentology (Haughton et al. 2003; 2009). Their formation processes (Baas et al. 2011), bed properties (Hussain et al. 2021), and distribution in relatively unconfined settings are now well understood (e.g., Kane & Pontén 2012; Spychala et al. 2017; Fonnesu et al. 2018). However, their occurrence in confined basins is less well documented (Patacci et al. 2014; Southern et al. 2015). The primary objective of this project is to examine the stratigraphic occurrence of hybrid event beds in confined deep-marine basins, to understand how their occurrence relates to the evolution of both the flows and the basin topography. This project will help develop our fundamental understanding of how deep-water sedimentary processes respond to confinement. The project will also help develop an applied understanding of the fill and rock properties of hybrid beds in confined basins, which are hosts of conventional resources (e.g., Kane & Ponten, 2012), sinks of organic carbon (e.g., Hussain et al. 2021), and potential hosts of man-made pollutants (e.g., Kane et al. 2020). This project will benefit from field studies in the famous Peïra Cava Basin, SE France (Amy et al. 2007); decades of prior studies by the wider research team provide a rigorous stratigraphic framework for the study. Additionally the study may exploit subsurface data of confined basin-fills from the Gulf of Mexico, including seismic, well, and core data, to characterise the occurrence of hybrid beds in subsurface architecture. Additional techniques that may be applied include organic petrography, palaeo-magnetism, and relational databasing to characterise the facies and architecture of the studied systems. However, the project is designed to be flexible, and can be adapted to align with the particular interests of the candidate. Aim and objectives: The primary aim of this project is to analyse the character and origin of hybrid event beds in confined basin fill, to help develop depositional and architectural models of deep-water stratigraphy. In addition, the research will involve development and employment of the Deep-Marine Architecture Knowledge Store (DMAKS), a relational database designed and populated by members of Turbidites Research Group 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 subsurface basin-fills, and process-based experimental and numerical modelling of confined basins. 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. <ul> <li class="Default" style="margin-left: 8px; text-align: justify;">What are the main drivers of flow transformation in confined basins? Multiple styles of hybrid event bed have been observed in confined basins, e.g. typical hybrid beds thought to have formed by de-lamination and entrainment of fines of the seafloor (Fonnesu et al. 2018); however, other types of hybrid beds, such as argillaceous sandstones have been observed at Peïra Cava, implying multiple modes of flow transformation and deposition.</li> <li>What are the relationship of hybrid beds with dune-like bedforms seen in proximal areas of the Peïra Cava Basin? Excellent exposures allow tracing of individual beds >10 km along the preserved length of the basin fill (Amy et al. 2007). These permit examination of downstream flow transformations. Preliminary studies have identified a downstream transition from dune bedforms to hybrid event beds. Furthermore, relationship of event beds to the lateral basin margins may be explored, with increasing confinement towards slopes interpreted as another trigger mechanism (Patacci et al. 2014).</li> <li>How does the composition of the genetically related turbidites and hybrid beds change downstream? The composition of turbidites has been documented to change downstream in confined basins (e.g., McArthur et al. 2016). This study can examine both the siliciclastic and organic composition of hybrid beds. Furthermore, the work may benefit from deployment of palaeo-magnetism studies to better constrain the age of the basin fill and its relation with other basins in the Annot System.</li> <li>How do intrinsic (e.g., local seafloor anomalies) and extrinsic (e.g., tectonics) factors control the stratigraphic distribution of hybrid beds? Understanding the generic controls on the distribution of hybrid beds may help understand their distribution in the subsurface. Can this study help provide data for modelling of hybrid bed prone successions in the subsurface? Can we improve on the population of reservoir modelling workflows in confined settings? What geological factors should we consider when selecting analogues for hybrid bed prone subsurface deposits? Hybrid beds are important for conventional resources, but should also be considered for our low-carbon future, i.e., effect on carbon capture and storage.</li> </ul> Methodology: Four principal methods will be applied to answer the questions above: <ol> <li class="Default" style="margin-left: 8px; text-align: justify;">Field studies will be undertaken in the Peïra Cava Basin to characterise the types, distribution and stratigraphic position of hybrid event beds in a confined basin fill. This will involve geological mapping, logging and potentially sampling of event beds across the basin fill. Deployment of an uncrewed aerial vehicle (UAV) will allow collection of high resolution imagery and may be used to build a 3D digital outcrop model.</li> <li>Subsurface studies of a confined basin-fill from the Gulf of Mexico will be undertaken to understand hybrid bed distribution at reservoir scale. The subsurface and outcrop studies may act as analogues at different hierarchies of data resolution.</li> <li>The data will be organised and stored in a relational database (DMAKS) and it will provide analogues for the study datasets.</li> <li>Laboratory studies of samples for magneto-stratigraphy, petrographic studies, and organic matter composition of hybrid beds will be used to characterise the age and composition of the studied deposits.</li> </ol> Eligibility and funding: 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. Experience of using GIS and seismic interpretation software would be useful, though is not essential. Skills in field-based geological data collection and field sedimentology and stratigraphy are desirable. Funding is provided by the Turbidites Research Group (www.trg.leeds.ac.uk). Full fees, maintenance and project costs will be covered. Self-funded or other means of funding are also welcome. Training: The successful applicant will join a large and vibrant research environment as part of 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) morphometric analysis of landscape features with a range of software (e.g. ArcGIS, Matlab or Python); ii) geological interpretation of seismic datasets using a range of software (e.g. Petrel, Paleoscan); iii) relational-database theory and practice (e.g. MySQL); iv) statistical analysis of large datasets; and potentially field-based techniques for the sedimentological and architectural analysis of clastic successions. The mixed pure- and applied-science nature of this research project will enable the candidate to consider a future career in either academia or industry. In addition, the candidate 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 (http://www.emeskillstraining.leeds.ac.uk). The successful candidate will be strongly encouraged and supported to present their results at international conferences and publish the outcomes of their research in international journals. Recommended Reading: Amy, L. A., Kneller, B. C. and McCaffrey, W. D. (2007). Facies architecture of the Gres de Peira Cava, SE France: landward stacking patterns in ponded turbiditic basins. Journal of the Geological Society 164: 143-162. <a href="http://dx.doi.org/10.1144/0016-76492005-019" style="color:#0563c1; text-decoration:underline">http://dx.doi.org/10.1144/0016-76492005-019</a> Baas, J. H., Best, J. L. and Peakall, J. (2011). Depositional processes, bedform development and hybrid bed formation in rapidly decelerated cohesive (mud-sand) sediment flows. Sedimentology 58(7): 1953-1987. <a href="https://doi.org/10.1111/j.1365-3091.2011.01247.x" style="color:#0563c1; text-decoration:underline">https://doi.org/10.1111/j.1365-3091.2011.01247.x</a> Fonnesu, M., Felletti, F., Haughton, P. D. W., Patacci, M. and McCaffrey, W. D. (2018). Hybrid event bed character and distribution linked to turbidite system sub-environments: The North Apennine Gottero Sandstone (north-west Italy). Sedimentology 65(1): 151-190. <a href="https://doi.org/10.1111/sed.12376" style="color:#0563c1; text-decoration:underline">https://doi.org/10.1111/sed.12376</a> Haughton, P. D. W., Barker, S. P. and McCaffrey, W. D. (2003). 'Linked' debrites in sand-rich turbidite systems; origin and significance. Sedimentology 50(3): 459-482. <a href="https://doi.org/10.1046/j.1365-3091.2003.00560.x" style="color:#0563c1; text-decoration:underline">https://doi.org/10.1046/j.1365-3091.2003.00560.x</a> Haughton, P. D. W., Davis, C., McCaffrey, W. D. and Barker, S. (2009). Hybrid sediment gravity flow deposits - Classification, origin and significance. Marine and Petroleum Geology 26(10): 1900-1918. <a href="https://doi.org/10.1016/j.marpetgeo.2009.02.012" style="color:#0563c1; text-decoration:underline">https://doi.org/10.1016/j.marpetgeo.2009.02.012</a> Hussain, A., Haughton, P. D. W., Shannon, P. M., Morris, E. A., Pierce, C. S. and Omma, J. E. (2021). Mud-forced turbulence dampening facilitates rapid burial and enhanced preservation of terrestrial organic matter in deep-sea environments. Marine and Petroleum Geology 130: 105101. <a href="https://doi.org/10.1016/j.marpetgeo.2021.105101" style="color:#0563c1; text-decoration:underline">https://doi.org/10.1016/j.marpetgeo.2021.105101</a> Kane, I. A. and Ponten, A. S. M. (2012). Submarine transitional flow deposits in the Paleogene Gulf of Mexico. Geology 40(12): 1119-1122. <a href="https://doi.org/10.1130/G33410.1" style="color:#0563c1; text-decoration:underline">https://doi.org/10.1130/G33410.1</a> Kane, I. A., Clare, M. A., Miramontes, E., Wogelius, R., Rothwell, J. J., Garreau, P. and Pohl, F. (2020). Seafloor microplastic hotspots controlled by deep-sea circulation. Science 368(6495): 1140-1145. <a href="https://doi.org/10.1126/science.aba5899" style="color:#0563c1; text-decoration:underline">https://doi.org/10.1126/science.aba5899</a> McArthur, A. D., Kneller, B. C., Wakefield, M. I., Souza, P. A. and Kuchle, J. (2016). Palynofacies classification of the depositional elements of confined turbidite systems: Examples from the Gres d'Annot, SE France. Marine and Petroleum Geology 77: 1254-1273. <a href="https://doi.org/10.1016/j.marpetgeo.2016.08.020" style="color:#0563c1; text-decoration:underline">https://doi.org/10.1016/j.marpetgeo.2016.08.020</a> Patacci, M., Haughton, P. D. W. and McCaffrey, W. D. (2014). Rheological complexity in sediment gravity flows forced to decelerate against a confining slope, Braux, SE France. Journal of Sedimentary Research 84(4): 270-277. <a href="https://doi.org/10.2110/jsr.2014.26" style="color:#0563c1; text-decoration:underline">https://doi.org/10.2110/jsr.2014.26</a> Southern, S. J., Patacci, M., Felletti, F. and McCaffrey, W. D. (2015). Influence of flow containment and substrate entrainment upon sandy hybrid event beds containing a co-genetic mud-clast-rich division. Sedimentary Geology 321: 105-122. <a href="https://doi.org/10.1016/j.sedgeo.2015.03.006" style="color:#0563c1; text-decoration:underline">https://doi.org/10.1016/j.sedgeo.2015.03.006</a> Spychala, Y. T., Hodgson, D. M., Prelat, A., Kane, I. A., Flint, S. S. and Mountney, N. P. (2017). Frontal and Lateral Submarine Lobe Fringes: Comparing Sedimentary Facies, Architecture and Flow Processes. Journal of Sedimentary Research 87(1): 75-96. <a href="https://doi.org/10.2110/jsr.2017.2" style="color:#0563c1; text-decoration:underline">https://doi.org/10.2110/jsr.2017.2</a>

<h2 class="heading">How to apply</h2>

Formal applications for research degree study should be made online through the <a href="https://www.leeds.ac.uk/research-applying/doc/applying-research-degrees">University's website</a>. Please state clearly in the research information section that the research degree you wish to be considered for is “Hybrid event beds in confined basins” as well as <a href="https://environment.leeds.ac.uk/see/staff/1407/dr-adam-mcarthur">Dr Adam McArthur</a> as your proposed supervisor. If English is not your first language, you must provide evidence that you meet the University's minimum English language requirements (below). As an international research-intensive university, we welcome students from all walks of life and from across the world. We foster an inclusive environment where all can flourish and prosper, and we are proud of our strong commitment to student education. Within the Faculty of Environment we are dedicated to diversifying our community and we welcome the unique contributions that individuals can bring, and particularly encourage applications from, but not limited to Black, Asian, people who belong to a minority ethnic community, people who identify as LGBT+; and people with disabilities. Applicants will always be selected based on merit and ability.

<h2 class="heading heading--sm">Entry requirements</h2>

Applicants to research degree programmes should normally have at least a first class or an upper second class British Bachelors Honours degree (or equivalent) in an appropriate discipline. The criteria for entry for some research degrees may be higher, for example, several faculties, also require a Masters degree. Applicants are advised to check with the relevant School prior to making an application. Applicants who are uncertain about the requirements for a particular research degree are advised to contact the School or Graduate School prior to making an application.

<h2 class="heading heading--sm">English language requirements</h2>

The minimum English language entry requirement for research postgraduate research study is an IELTS of 6.0 overall with at least 5.5 in each component (reading, writing, listening and speaking) or equivalent. The test must be dated within two years of the start date of the course in order to be valid. Some schools and faculties have a higher requirement.

<h2 class="heading">Funding on offer</h2>

Funding is provided by the Turbidites Research Group (www.trg.leeds.ac.uk). Full fees, maintenance and project costs will be covered. Self-funded or other means of funding are also welcome.

<h2 class="heading">Contact details</h2>

Adam McArthur <a href="mailto:a.mcarthur@leeds.ac.uk">a.mcarthur@leeds.ac.uk</a>, +44 (0)113 343 7533 <a href="http://trg.leeds.ac.uk/" style="color:#0563c1; text-decoration:underline">http://trg.leeds.ac.uk/</a> For further information on how to apply please contact the Graduate School Office Admissions team e: <a href="mailto:EMAIL@leeds.ac.uk">env-pgr@leeds.ac.uk</a>

<h3 class="heading heading--sm">Linked research areas</h3>