I specialize in characterising the geology and physical character of the seabed and sub-seabed. I apply expertise in a number of complementary fields including habitat mapping (in support of the UK & UK Overseas Territory Marine Protected Area network), offshore renewables (production of 3D geological models) and palaeoenvironmental research (to improve models of past and active environmental change). My recent work has two themes: assessing the dynamics, configuration, and sedimentary record of former ice-sheets through integration of geophysical and geological data from the UK continental shelf; and studying the geomorphology and sediments of hadal (>6000 m water depth) ecosystems like subduction trenches. I have extensive field experience carrying out research and commercial projects primarily in the NE Atlantic Ocean / North Sea but also including the Mediterranean Sea, Gulf of Mexico, Japan Sea, Pacific Ocean, Arctic Ocean and offshore Antarctica.
Heather Stewart’s Biography
- 2021 – ongoing : Honorary Assistant Professor at Heriot-Watt University
- 2015 – 2022 : PhD Research Student (part-time) at University of Stirling
- 2001 – ongoing : Marine Geologist, British Geological Survey
- 2000 – 2001 : Marine Geologist with Caledonian Geotech
- 1997 – 2001 : BSc (Hons), University of Glasgow, Geology and Applied Geology
- Applied offshore mapping initiatives – Mapping the offshore sea-bed substrate, geomorphology and Quaternary geology utilising shallow seismic, sidescan sonar, multibeam echosounder and sample data. Development/promotion of new and novel techniques for acoustic data interpretation
- Multidisciplinary study of the Hadal Zone – Working cross discipline to explore and research subduction trenches such as the South Shetland Trench (sub-Antarctica), Kermadec Trench (SW Pacific) and Atacama Trench (E Pacific). This work is in collaboration with researchers at University Western Australia, the HADAL Center in Denmark, University of Newcastle and NIWA in New Zealand
Current projects and collaborations
- HOT: Hadal zones of our Overseas Territories is a multi-disciplinary program that will deliver a step-change in our understanding of the fundamental ecological and geological processes in the South Sandwich Trench (SST). The SST reaches water depths of around 8100m and uniquely is the only sub-zero hadal environment on Earth. This project will improve understanding of marine biodiversity and geodiversity to fill an identified knowledge gap supporting the existing Marine Protected Area and obligations under the Convention of Biological Diversity. Darwin Initiative (Defra) funded grant through Darwin Plus Round 7.
- EMODnet-Geology – Work Package Leader for the “Submerged Landscapes” theme and coordinate BGS contribution to the wider project across all Work Package themes (e.g. geomorphology, seafloor substrates). As Work Package Leader we have, for the first time, collated and delivered pan-European data and information on Submerged Landsystems, an invaluable resource for improving our understanding of human history and environmental change over geological time.
- Late Cenozoic palaeo-climate of NW Europe and implications for subsurface CO2 containment (CENOSTORE) – Virtual Site Survey – The main aim of CenoStore is to recover the highest resolution Quaternary deep shelf record of mid- to mid-high latitude climatic and environmental variation in the eastern Hemisphere. The aim of this virtual site survey is therefore to identify zones of high sediment accumulation rates and stratigraphic completeness in the mud prone lower clinothem slope positions away from submarine channels and fans (readily detectable on 3D seismic attribute maps) with a view to identify sites for future scientific research drilling. I am a Co-Investigator on this NERC funded project led by University of Manchester.
Papers in progress
- Stewart, H A, Dove, D, Bongiovanni, C, and Jamieson, A J. (In Review) The Seafloor Geomorphology of the South Sandwich Trench, Southern Ocean. Journal of Maps.
- Stewart, H A, James, B, Bradwell, T, et al. (In Prep) Seafloor glacial landform assemblages and the functional role they play to support critically endangered habitats, Inner Sound offshore Skye, NW Scotland. Scottish Journal of Geology.
- Jamieson, A J, Giles, G T, and Stewart, H A. (In Prep) Hadal zones of the southeast Pacific and East Indian oceans.
- Stewart, H A, and Bradwell, T. (In prep). Shallow seafloor glacial features reveal ice streaming and ice sheet re-advance of the last British Ice Sheet, Western North Sea Basin. Journal of Maps.
- Weston, J N J, Jensen, E L, Hasoon, M S R, Kitson, J N J, Stewart, H A, and Jamieson A J J. 2022. Barriers to gene flow in the deepest ocean ecosystem: Evidence from global population genomics of a cosmopolitan amphipod. Science Advances, 8, eabo6672. DOI: 10.1126/sciadv.abo6672
- Oguri, K, Masqué, P, Zabel, M, Stewart, H A, MacKinnon, G, Rowden, A, Berg, P, Wenzhöfer, F, and Glud, R N. 2022. Sediment accumulation and carbon burial in four hadal trench systems. Journal of Geophysical Research: Biogeosciences, Vol. 127(10), e2022JG006814. https://doi.org/10.1029/2022JG006814
- Jamieson, A J, Stewart, H A, Weston, J N J, Lahey, P, and Vescovo, V. 2022. Hadal biodiversity, habitats and potential chemosynthesis in the Java Trench, Eastern Indian Ocean. Frontiers in Marine Science. https://doi.org/10.3389/fmars.2022.856992
- Stewart, H A, Cooper, R M, and Lewis, W D. 2022. Reprocessing of CHP datasets (HI1567 & HI1570) and Seafloor Substrate Interpretation for Selected Areas: Inner Sound off Skye on the West Coast of Scotland. British Geological Survey Commissioned Report, CR/21/080. 44pp. https://nora.nerc.ac.uk/id/eprint/531840/
- Bongiovanni, C, Stewart, H A, and Jamieson, A J. 2022. High-resolution multibeam sonar bathymetry of the deepest place in each ocean. Geoscience Data Journal. https://doi.org/10.1002/gdj3.122
- Jamieson, A J, and Stewart, H A. 2021. Hadal Zones of the Northwest Pacific Ocean. Progress in Oceanography, Vol. 190. https://doi.org/10.1016/j.pocean.2020.102477
- Jamieson, A J, Stewart, H A, Weston, J N J, and Bongiovanni, C. (2021) Hadal fauna of the South Sandwich Trench, Southern Ocean: Baited camera survey from the Five Deeps Expedition. Deep-Sea Research II, Topical Studies in Oceanography, 104987. https://doi.org/10.1016/j.dsr2.2021.104987
- Vescovo, V, Jamieson, A J, Lahey, P, McCallum, R, Stewart, H A, and Machado, C. (2021) Safety and conservation at the deepest place on Earth: A call for prohibiting the deliberate discarding of nondegradable umbilicals from deep-sea exploration vehicles. Marine Policy, Vol. 128, 104463. https://doi.org/10.1016/j.marpol.2021.104463
- Glud, R N, Berg, P, Thamdrup, B, Larsen, M, Stewart H A, Jamieson, A J, Glud, A, Oguri, K, Sanei, H, Rowden, A A, and Wenzhöfer, F. 2021. Hadal trenches are dynamic hotspots for early diagenesis in the deep-sea. Nature Communications Earth and Environment, 2:21. https://doi.org/10.1038/s43247-020-00087-2.
- Weston, J N J, Peart, R A, Stewart, H A, Ritchie, H, Piertney, S B, Linley, T D, and Jamieson, A J. 2021. Community structure of scavenging amphipods in the Wallaby-Zenith Fracture Zone: Extending the hadal paradigm beyond subduction zones. Marine Biology, Vol. 168, 1. https://doi.org/10.1007/s00227-020-03798-4
- Neat, F C, Jamieson, A J, Stewart, H A, Narayanaswamy, B E, Collie, N, Stewart, M, and Linley, T D. 2019. Visual evidence of reduced seafloor conditions and indications of a cold-seep ecosystem from the Hatton–Rockall basin (NE Atlantic). Journal of the Marine Biological Association of the United Kingdom, v. 99, 271-277. doi.org/10.1017/S0025315418000115.
- Stewart, H A, and Jamieson, A J. 2019. The five deeps: the location and depth of the deepest place in each of the world’s oceans. Earth Science Reviews, 197, 102896.
- Roberts, D H, Grimoldi, E, Callard, L, Evans, D J A, Clark, C D, Stewart, H A, Dove, D, Saher, M, Ó Cofaigh, C, Chiverrell, R C, Bateman, M D, Moreton, S G, Bradwell, T, Fabel, D, and Medialdea, A. 2019. The mixed-bed imprint of the North Sea Lobe in the western North Sea. Earth Surface Processes and Landforms, v. 44, 1233-1258.
- Stewart, H A, and Jamieson, A J. 2018. Habitat heterogeneity of hadal trenches: considerations and implications for future studies. Progress in Oceanography, v. 161, 47-65.
- Stewart, H A, and Long, D. 2016. Glacigenic debris flows observed in 3D seismic high-resolution seafloor imagery, Faroe–Shetland Channel, NE Atlantic. From: Dowdeswell, J A, Canals, M, Jakobsson, M, Todd, B J, Dowdeswell, E K and Hogan, K A (eds). Atlas of Submarine Glacial Landforms: Modern, Quaternary and Ancient. Geological Society, London, Memoirs, 46. © The Geological Society of London, 2016. DOI: 10.1144/M46.94
- Piechaud, N, Downie, A, Stewart, H A, Howell, K L. 2015. The impact of modelling method selection on predicted extent and distribution of deep-sea benthic assemblages. Earth and Environmental Science Transactions of the Royal Society of Edinburgh, 105(4), 251-261.
- Davies, J S, Stewart, H A, Narayanaswamy, B E, Jacobs, C, Spicer, J, Golding, N, Howell, K L. 2015. Benthic assemblages of the Anton Dohrn Seamount (NE Atlantic): defining deep-sea biotopes to support habitat mapping and management efforts with a focus on Vulnerable Marine Ecosystems. PLOS One, Vol 10(5): e0124815.
- Lark, R M, Marchant, B P, Dove, D, Green, S L, Stewart, H, Diesing, M. 2015. Combining observations with acoustic swath bathymetry and backscatter to map seabed sediment texture classes: the empirical best linear un-biased predictor. Sedimentary Geology, Vol. 328, 17-32.
- Piechaud, N, Downie, A, Stewart, H A, Howell, K L. 2015. The impact of modelling method selection on predicted extent and distribution of deep-sea benthic assemblages. Earth and Environmental Science Transactions of the Royal Society of Edinburgh, Vol. 105(4), 251-261. doi: 10.1017/S1755691015000122
- Ross, L K, Ross, R E, Stewart, H A, Howell, K L. 2015. The influence of data resolution on predicted distribution and estimates of extent of current protection of three ‘listed’ deep-sea habitats. PLOS One, Vol 10(10), e0140061. doi: 10.1371/journal.pone.0140061.
- Stewart, H A, Davies, J S, Guinan, J C, and Howell, K L. 2014. The Dangeard and Explorer Canyons, South Western Approaches UK: Geology, sedimentology and newly discovered cold-water coral mini-mounds. Deep-Sea Research II, Topical Studies in Oceanography, Vol. 104, 230-244.
- Stewart, H A, Bradwell, T, Carter, G D O, Dove, D, and Gafeira, J. 2021. Chapter 6: Geomorphology of the Offshore Continental Shelf. 117-134 in World Geomorphological Landscapes: Landscapes and Landforms of Scotland (J Gordon and C Ballantyne Editors). (London Springer)
- Jamieson, A J, Stewart, H A, Rowden, A A, and Clark, M R. 2020. Geomorphology and benthic habitats of the Kermadec Trench, SW Pacific Ocean. 949-966 in: Harris, P.T, Baker, E.K (Editors). Seafloor geomorphology as benthic habitat: GeoHab Atlas of seafloor geomorphic features and benthic habitats (Second Edition). Elsevier Insights Series. (Elsevier, London, UK).
- Stevenson, A, Stewart, H A, and Ziska, H. 2011. Sea-bed geology and Environment. 229-238 in Ritchie, J D, Ziska, H, Johnson, H, and Evans, D (editors). 2011. Geology of the Faroe-Shetland Basin and adjacent areas. British Geological Survey Research Report, RR/11/01; Jarðfeingi Research Report RR/11/01. (HMSO: London)
Selected media and grey literature
- Interview on the Deep Sea Podcast “009 – Geology with Heather Stewart” https://www.armatusoceanic.com/podcast/009-geology-with-heather-stewart
- “Oceans’ extreme depths measured in precise detail” https://www.bbc.co.uk/news/science-environment-57063396. BBC Radio 4 Today Programme interview (approx. 2 min long) and BBC1 Breakfast TV interview (approx. 8 min long) on 11th May 2021. Clips available on request. BGS Press release: https://www.bgs.ac.uk/news/deepest-points-of-the-indian-ocean-and-southern-ocean-revealed/
- “Expedition Deep Ocean” is a five-part documentary released in 2021 on streaming service Discovery Plus. Filmed by multi-BAFTA and Emmy Award winning Atlantic Productions. The series follows the global journey of the Five Deeps Expedition on which I was Expedition Geologist.
- “Uncovering secrets of the Mariana Trench” https://www.bgs.ac.uk/news/uncovering-secrets-of-the-mariana-trench/
- Stewart, H A. 2021. Deeper, darker colder – exploring the South Sandwich Trench. 1-8 In The Edinburgh Geologist, Issue No. 69, Spring 2021. (RW Gatliff Editor). (The Edinburgh Geological Society) [https://edinburghgeolsoc.org/eg_pdfs/edinburgh-geologist-69.pdf]
- Stewart, H A, Jamieson, A J, and Bongiovanni, C. 2019. Exploring the Deepest Points on Planet Earth. Hydro International Magazine, v. 24 (3), 22-25. https://www.hydro-international.com/magazine/may-june-2019
- ArcGIS and digital mapping
- IHS Kingdom seismic interpretation software
- QPS Qinsy / Fledermaus (multibeam data processing and visualisation)
- CARIS (multibeam data processing)
- Various MS Office and image production software packages
- Fellow of the Geological Society of London
Boards and committees
- Editorial Board: Scottish Journal of Geology
- Member of the Strategic Advisory Board, Institute of Life and Earth Sciences, Heriot-Watt University, UK
- Member of the Marine Alliance for Science and Technology Scotland Deep-Sea Forum (Convenor since 2016)
- Member of International Scientific Committee for GeoHab