Basin Dynamics Research Group

I studied my undergraduate course at the University of Bristol between 2008 and 2011 and graduated with a BSc Hons in Geology. Within a month of graduating I started here at Keele to begin working on the ‘Structural and Geodynamic Evolution of the Barmer Basin, Rajasthan, India’ project with the Basin Dynamics Research Group (BDRG).

During my time at Keele I have undertaken numerous trips to India for both fieldwork involving detailed mapping of exposed rotational fault blocks combined with sedimentary logging, alongside meetings at Cairn India’s head office in Gurgaon, Haryana. I have attended numerous undergraduate field trips with Keele including the Paradox Basin (USA), Cantabria (Spain), Mull (Scotland) and Pembrokeshire (S.Wales). Other field experience includes a month-long period of undergraduate mapping on the Island of Syros, Greece. Two short periods of work experience with engineering geology firms, another geological interest of mine, have also been undertaken.

Affiliations:

• Geological Society of London: Fellow (GSL)
• Student Member of the American Association of Petroleum Geologists (AAPG)
• Student Member of the Tectonic Studies Group (TSG)

The Structural and Geodynamic Evolution of the Barmer Basin, Rajasthan, India

Supervisory Team:   S. M. Clarke¹, S. S. Egan¹, S. D. Burley², N. Whiteley², V. Kothari²

¹Basin Dynamics Research Group, Geography,  Geology and the Environment, Keele University, Keele, Staffordshire, ST5 5BG, U.K.

²Cairn India PTY, 3^rd floor, Vipul Plaza, Sun City, Sector 54 Gurgaon 122 002, India

Project Aims and Objectives:

• Investigate the large, lithospheric-scale geodynamic evolution of the basin in the context of western India and its post-Jurassic tectonism. This will be done by modelling 2D sections of the basin in the north and the south and comparing the results with detailed interpretations of available seismic data and corresponding sections of 2D gravity models.
• Study exposed fault-block scale features that will drive detailed sub-surface, seismic interpretations local to the outcrops studied. Further constraint, where available, will be provided by well data.

Fatehgarh Ridge, northern Barmer Region

The Barmer Basin is a long (≈200km) and narrow (<50km) extensional basin situated in the state of Rajasthan, NW India (see location map) and is the northernmost extent of the West Indian Rift-System^1,2. Rift-onset occurred at the Cretaceous – Paleogene boundary, however recent workers have suggested the presence of Mesozoic (likely Jurassic) sub-basins situated below Deccan-related volcanics based on gravity modelling³. These basins are not immediately clear seismically due to the effect of the overlying volcanics. The cause of rifting is not yet clear but two probable mechanisms exist;

1) break-away of the Seychelles microcontinent from India¹;

2) plume-lithosphere interactions as India passed over the Reunion hotspot¹.

A combination of both rift-mechanisms is also plausible. Both events are dated at the Cretaceous – Paleogene boundary. Rifting continued into the Paleogene as a result of intra-continental tension created from the onset of collision between India and Eurasia, an event which caused extensive inversion in the north of the basin³. Continued rifting is seen as a series of rift-pulses in the basin fill that dominantly consists of continental fluvial and lacustrine deposits that show a general wetting-upwards trend^2,4. Early workers suggested marine influxes into the basin at various intervals from rift-initiation, but the basin is thought to have remained non-marine until latest Paleocene times⁵.

With surface outcrop being very sparse within the basin, understanding of the basins’ structure has dominantly been attained through interpretation of sub-surface data alone. Although interpretation of sub-surface data provide good, fully-plausible structural models, the nature of these interpretations is highly variable based upon the interpreters experience and expertise as well as pre-conceived structural models. It is important to ‘ground-truth’ interpretations ensuring that what is observed at outcrop matches sub-surface models

It is the purpose of this study to use the results of outcrop-based investigation to generate both surface and sub-surface structural models that explain the evolution of the eastern and western margins of the Barmer Basin. Once understood, these results will be used to interpret narrow three-dimensional, basin-wide sections that are to be used for lithosphere-scale geodynamic modelling across the northern and southern basin (Figure 2). Geodynamic models will also be constrained by gravity modelling.

Upon completion, an in-depth understanding of the structural styles seen within the basin will be achieved providing an understanding into the extent that pre-rift basement fabric and Himalayan-related inversion created the basin architecture seen today. In conjunction with this, geodynamic modelling will show how and why the larger basin-architecture was generated as a result of the lithospheric reaction to tension and by combining this with gravity modelling will provide insights into basin unknowns.

References:

¹ Compton, P. M. 2009. The Geology of the Barmer Basin, Rajasthan, India, and the origins of its major oil reservoir, the Fatehgarh Formation. Petroleum Geoscience, 15, pp. 117-130

² Clarke, S. M. 2010. Outcrop Studies in the Barmer Basin, Rajasthan, India. Commisioned Report on Behalf of Cairn India PTY

³ Hus, R. Cathro, D. 2010. Barmer-Cambay-Kutch Structural GIS and SEEBASE^TM, Confidential Report to Cairn India by Frogtech Pty Ltd.

⁴ Taylor, R. Raine, R. Sunder, V. R. Mishra, P. 2010. Barmer Basin Outcrop Work Summary. Initial Ichron Ltd report for Cairn India Ltd.

⁵ Sunder, V. R. Whiteley, N. J. Raine, R. Taylor, A. Kothari, V. Burley, S. 2012. The Mesozoic to Cenosoic Stratigraphy of the Barmer Basin, Rajasthan, India. Cairn India Ltd draft Internal report