EAGE London: From Ancient Rivers to CO2 storage

The talk will have a hybrid form: in-person at Imperial College, London and broadcasted ONLINE.

Link to the webinar will be provided via e-mails to registered attendees: first e-mail will be sent two days before the event and the second one just 2 hours before the event. Do not register too late!

Lecture Theatre 2.28

Agenda (UK time)

18:30-18:35 Introduction and Announcements

18:35-19:00 Multiscale Characterization of Sedimentological Heterogeneity in the Bunter Sandstone Formation with Application to CO2 Storage

19:00-19:20 A new source-to-sink synthesis of the Middle Triassic Helsby Sandstone Formation (Sherwood Sandstone Group) river systems in the British Isles

19:20-19:35 Q&A

from 19:35 Informal discussion and networking

Presenters

Prof Gary Hampson is a Professor of Sedimentary Geology in the Department of Earth Science and Engineering, Imperial College London where he also holds affiliations with the Energy Futures Lab, the Grantham Institute, and the Novel Reservoir Modelling and Simulation (NORMS) research group. He teaches and researches sedimentology, sequence stratigraphy, and its applications to the characterization of rocks and fluid flow in the subsurface for geo-energy. Gary’s research is grounded in the insights provided by outcrop geology, but he is an advocate of collaborative, cross-disciplinary research that integrates different data types and analytical approaches.

Xiang Yan is a PhD student on the SSCP DTP scholarship at Imperial College London. His current research focuses on the downstream variations in sediment mineralogy and grain size within river systems, with direct application to Carbon Capture and Storage (CCS) reservoir characterization. Holding an MSci degree from Imperial College London, Xiang has a deep technical background in Sedimentology, Climate Science, and Planetary Science. Equipped with a keen geological mindset, a history of high academic performance, and an enthusiasm for continuous learning, Xiang actively seek new opportunities in both research and industry that leverage subsurface geoscience for the energy transition.

Talks outline

Talk1: Multiscale Characterization of Sedimentological Heterogeneity in the Bunter Sandstone Formation with Application to CO2 Storage
Effective CO2 storage in subsurface reservoirs requires an understanding of the effects of geological heterogeneity across various scales. We address multiscale reservoir characterization using nested, hierarchical models in which properties resolved at smaller scales are systematically upscaled and used as inputs for larger-scale models. This approach preserves the effects of critical heterogeneities while enabling computationally efficient simulation of CO2 plume behaviour and trapping efficiency. This study develops a multiscale reservoir characterization framework for the Bunter Sandstone Formation, a Triassic fluvial succession widely targeted for CO2 storage across northwestern Europe, including at the Endurance CO2 storage site, offshore UK. The results of facies analysis of core and outcrop analogues, minipermeameter measurements, thin section petrography, and numerical modeling have been integrated to characterize heterogeneity at scales ranging from lamina (mm) to architectural elements (10s m). Twelve lithofacies were identified and grouped into three facies associations, and three architectural elements were defined based on the stacking patterns and geometrical configuration of lithofacies. Facies-scale permeability varies over three orders of magnitude (0.18–5400 mD), and is primarily controlled by grain size, clay content, and cementation. Representative Elementary Volume (REV) analysis revealed that the effective permeability for different lithofacies stabilizes at scales significantly larger than those of typical core plugs and exhibits high anisotropy. Effective permeability correlates linearly with the proportion of high-permeability (clay-poor) lithologies in each facies. The resulting values of effective permeability for different facies were populated in architectural element-scale models. Simplifying these models of architectural elements by grouping lithofacies into two or three permeability-based categories resulted in estimated values of effective permeability at this scale that are within 10-20% of those for models containing twelve distinct lithofacies. These findings indicate that simplified architectural element-scale models generated within a nested modeling framework can preserve key flow properties while enabling efficient simulation of CO2 storage reservoirs.

Talk 2: A new source-to-sink synthesis of the Middle Triassic Helsby Sandstone Formation (Sherwood Sandstone Group) river systems in the British Isles
Sediment grain size and mineralogical composition change in a sediment routing system from source to sink. A better understanding of sediment routing therefore allows improved predictions to be made of the volumetrics and bulk mineralogical composition of sandstone-reservoir fairways for carbon capture and storage (CCS). The Triassic Helsby Sandstone Formation (HSF) of the Sherwood Sandstone Group (SSG), and lowermost Mercia Mudstone Group (MMG) of the British Isles were deposited by a major, north-flowing river system, the Sherwood-2 River. The SSG is a significant target for CCS, however despite recent and ongoing interest, source-to-sink sediment routing, key in understanding regional-scale trends, has remained unappraised for the SSG and MMG for the past three decades.To this end, we present a new depositional model for the HSF, tracing the fluvial system from its source region in north France, into and beyond the Irish Sea. We begin by constructing a new, integrated litho- and chronostratigraphic model to correlate key units across the British Isles. We then present sediment isopachs and volumes for the first time. We resolve existing paleogeographic discrepancies using existing sedimentological, provenance and paleocurrent data, supplemented by a new synthesis of bulk sediment mineralogy across the British Isles. Using the resources we have created, we then present a unified, updated sediment routing map for the Sherwood-2 system, including an appraisal of source areas. Importantly, we observe substantial differences in sediment bulk-mineralogy between the south and north of the sediment routing system, likely signifying that aside from the primary source area of the Sherwood-2 in North France, substantial tributaries were able to modify the composition of the HSF along its course.