Description

Exploring the Sea Floor

Description - summary of the module content

Module description

We know more about the surface of the Moon than we do the topography of our ocean floor here on Earth. Less than 0.05% of the sea bed has been mapped to a level of detail sufficient to identify, for example, an airplane wreckage or undersea volcanic vent. The need to map the bottom of our seas has, therefore, never been more important. These maps are key to representing the features and layout of our world and underpin the understanding of its function. In the marine realm, bathymetric surveys help to inform marine planning and management, are used in decision-making for the utilisation of resources (e.g. aggregate dredging), and form important tools to ensure sea-floor resources, including sea-animal habitats, are both valued and cared for. The scientific applications of exploring the sea floor extend throughout the Earth sciences, from a basic understanding of what the sea floor is made of and what it looks like, to how the sea floor formed and has been shaped and changed over time, by glaciers, by tectonic processes, and by humans. Sea-floor maps also form the basis of ecological work exploring communities and their habitats, from the shallowest shelves to the deepest ocean trenches, while archaeologists explore the sea bed to produce maps of the potential locations of prehistoric materials and historical finds in the form of shipwrecks.

Module aims - intentions of the module

This module introduces you to the techniques, theory, practice, and applications of sea-floor mapping and exploration, with an emphasis on marine acoustic tools. The module will be rewarding for its mix of theory and cutting-edge research; content will include data and examples from previous and active research projects (e.g. Research Council funded consortium project studying sea-floor life on the East Scotia Ridge; mapping the sea-bed under Pine Island Glacier with the Autosub-3 AUV)  involving the module convenor.

The practical elements of the module should provide you with a set of desirable skills for further study or future employment in a range of marine careers: marine geology, geophysics, maritime archaeology, environmental surveying and management, and marine industries.  

The module aims are to provide you with:

• a grounding in theoretical concepts of sea-floor mapping and exploration techniques for work in a number of shallow marine and deep-sea environments
• the practical skills to undertake the processing and interpretation of selected marine acoustic datasets (specifically, multibeam bathymetry systems) using specialist software
• an ability to evaluate a range of sea-bed exploration and mapping applications, their scientific relevance and importance, the underlying physical processes, and utility in the geographical and environmental sciences.

Intended Learning Outcomes (ILOs)

ILO: Module-specific skills

On successfully completing the module you will be able to...

• 1. Evaluate theoretical concepts, and sea-floor mapping and exploration techniques for work in a number of shallow marine and deep-sea environments
• 2. Outline in detail the application of sea-floor exploration techniques in environmental science, and discuss comprehensively their scientific relevance and importance
• 3. Describe in detail key physical processes acting upon and occurring at the seabed for a number of different environments
• 4. Demonstrate practical skills in the processing and presentation of multibeam bathymetry datasets, and reporting of results in a professional manner
• 5. Demonstrate practical ability and insight in the scientific interpretation of sea-floor data

ILO: Discipline-specific skills

On successfully completing the module you will be able to...

• 6. Illustrate and discuss the contested and provisional nature of knowledge and understanding, particularly with regard to areas encompassing sea-floor science
• 7. Describe, apply and evaluate the diversity of specialised techniques and approaches involved in analysing geographical information
• 8. Draw upon a diverse range of approaches to generate knowledge and understanding, including for example, independent reading, group seminars, and computer-based practicals
• 9. Assess the nature of change within physical environments
• 10. Assess the significance of spatial relationships and the temporal distribution of physical processes on physical and human environments.

ILO: Personal and key skills

On successfully completing the module you will be able to...

• 11. Communicate ideas, principles and theories effectively and fluently by written and verbal means
• 12. Develop a sustained and reasoned argument
• 13. Identify, acquire, evaluate and synthesise data from a range of sources
• 14. Undertake independent/self-directed study/learning to achieve consistent, proficient and sustained attainment
• 15. Develop command line ability in a Linux shell
• 16. Effectively handle, process and interpret geophysical and geospatial information

Syllabus plan

Syllabus plan

The module is concerned with exploring the part of the Earth that is covered by our seas and oceans, and will describe exploring the sea floor through a logical sequence of context, theory, practice and applications, split broadly into two parts. Part 1 will use practical data examples, integrated with observations, to help understand both techniques of exploration and surveying, underlying theory, and some of the fundamental processes occurring at the sea floor. Part 2 is divided into topics covering different geographic portions of the world’s oceans. Applied examples will be supported by reading group seminars, which will be held regularly throughout the term, and in which we will discuss active research on sea-floor surveying, environments, and scientific challenges across disciplines. Practical sessions will afford you experience of working hands-on with a marine geophysical dataset, seeing the processing through from raw data to scientific interpretation. Summative data-led coursework will emulate the layout of a commissioned report by industry.

Anticipated module content:

Part 1: Theory, techniques and practice

• Introduction to Earth’s Ocean Floor
  • The Shape and the make-up

• Seabed processes: from shelf to abyss
  • Imaging the seabed: methods and theory in obtaining bathymetry
  • Reading seminar 1

• Pinging principles: multibeam mapping
  • Practical 1 – 3-hour computer lab

• Seeing through the Sea floor: profiling and seismic
  • Reading seminar 2

• What lies beneath: Analysis and Interpretation techniques for bathymetry and sub-bottom data
  • Practical 2 – 3-hour computer lab

Part 2: Scientific challenges and applications

• Getting to the Bottom of it: science in Earth’s oceanic trenches
  • Practical 3 – 2-hour in class/desk-based

• Continental shelves: The cryosphere and the marine environment
  • Reading seminar 4

• Coastal platforms: Seabed habitats and shipwrecks
  • Reading seminar 5

• Mid-ocean ridges: Hydrothermal vents, underwater volcanoes, and biogeography
  • Practical 4 – 2-hour computer lab

• Arctic seas: Industry, Icebergs, and pipelines; module conclusion

Learning and teaching

Learning activities and teaching methods (given in hours of study time)

Details of learning activities and teaching methods

Assessment

Formative assessment

Summative assessment (% of credit)

Details of summative assessment

Re-assessment

Details of re-assessment (where required by referral or deferral)

Re-assessment notes

Deferral – if you miss an assessment for certificated reasons judged acceptable by the Mitigation Committee, you will normally be either deferred in the assessment or an extension may be granted. The mark given for a re-assessment taken as a result of deferral will not be capped and will be treated as it would be if it were your first attempt at the assessment.

Referral – if you have failed the module overall (i.e. a final overall module mark of less than 40%) you will be required to sit a further examination or submit a further assessment as necessary. If you are successful on referral, your overall module mark will be capped at 40%.

Resources

Indicative learning resources - Basic reading

Useful module books:

• Blondel, P., Murton, B., 1997. Handbook of Seafloor Sonar Imagery. Wiley-Praxis Series in Remote Sensing.
• Dowdeswell, J. A., Canals, M., Jakobsson, M., Todd, B. J., Dowdeswell, E. K., & Hogan, K. A., (eds) 2016. Atlas of Submarine Glacial landforms: Modern, Quaternary and Ancient. Geological Society, London, Memoirs, 46, http://doi.org/10.1144/M46.

Indicative learning resources - Web based and electronic resources

• ELE page: http://vle.exeter.ac.uk/course/view.php?id=6885

Module has an active ELE page

Indicative learning resources - Other resources

Indicative journal articles:

• Micallef, A., LeBas, T. P., Huvenne, V. A. I., Blondel, P., Huenerbach, V. and Deidun, A., 2012. A multi-method approach for benthic habitat mapping of shallow coastal areas with high-resolution multibeam data. Continental Shelf Research, 39-40, pp. 14-26.
• Gupta, S., Collier, J.S., Palmer-Felgate, A., Potter, G. 2007. Catastrophic flooding origin of shelf valley systems in the English Channel. Nature, 448, 342-345.
• Rogers AD, Tyler PA, Connelly DP, Copley JT, James R, Larter RD, Linse K, Mills RA, Garabato AN, Pancost RD, et al (2012). The discovery of new deep-sea hydrothermal vent communities in the southern ocean and implications for biogeography. PLoS Biol, 10(1).

Key words search

Sea-floor, oceans, bathymetry, remote sensing, cryosphere, habitats, geophysics, geology