Sedimentology and Stratigraphy - 2021 entry

This module will provide the fundamentals of sedimentology, tracing the physical and sedimentary processes from source terrain to sedimentary rock. You will review depositional sedimentary environments and the observations required to infer these from sedimentary successions. Practical work will include optical microscopy and hand specimen description. A central part of the module is a six-day field course to the Wessex Basin of southern England where your ability to describe and interpret sedimentary rocks in the field will be developed. You will also learn about the principal techniques used to date, correlate, and interpret the origin of sedimentary strata. In this module you will learn how fossils, stable and radioisotopes, orbital cycles, rock magnetic properties and geophysical or geochemical logs can be combined to provide an integrated understanding of how we date rocks and how sediments are deposited. In addition, you will be introduced to sedimentary basins and the stratigraphic methods used to reconstruct their depositional histories.

1. Provide an understanding of sedimentary processes and resultant sedimentary products;

2. Allow an understanding of process-based sedimentology to be applied to recognise a range of siliciclastic and carbonate depositional environments from the rock record;

3. Introduce the principal classes of sedimentary basin, explore their origins and history of infill, and discuss how the interactions of tectonics, sea-level change, sediment supply and palaeoclimate affect the sediment infill;

4. Provide a grounding for petrographic descriptions and interpretations of siliciclastic and carbonate deposits;

5. Provide grounding in the principal techniques in stratigraphy, particularly isotope stratigraphy, cyclostratigraphy, geophysical log interpretation, and magnetostratigraphy and sequence stratigraphy.

On successful completion of this module, you should be able to:

Module Specific Skills and Knowledge:

1 Be able to interpret depositional history and process from field, borehole and seismic reflection datasets.

2 Understand the principles of sedimentology covering weathering, fluid flows at the Earth’s surface, mechanisms of sediment erosion, transportation and deposition.

3 Describe and measure commonly occurring physical, chemical and biological sedimentary structures and interpret their process of formation and significance.

4 Understand how to interpret sedimentary facies and have an ability to apply this knowledge to the recognition and process-based interpretation of a range of both siliciclastic (e.g. fluvial, deltaic, shallow marine, deep marine) and carbonate (e.g. carbonate platforms, pelagic carbonates) depositional environments.

5 Describe and interpret the detrital and diagenetic mineralogy of clastic and carbonate sedimentary rocks based on transmitted light microscopy and hand specimen description.

6 Understand the basis for commonly used methods of stratal correlation, be able to use these methods in a range of depositional settings, and understand their significance for reconstruction of planetary history.

7 Understand and explain the methods by which geologists construct absolute and relative chronology for sedimentary successions.

8 Have a knowledge of sedimentary basins, their likely origins, and the major controls on their sedimentary infill.

Discipline Specific Skills and Knowledge:

9 Integrate stratigraphic observations across a variety of scales and using a variety of methods.

10 Describe and interpret sedimentary rocks whilst carrying out geological fieldwork.

11 Use your field and microscope based descriptions of sedimentary rocks to reconstruct past environmental changes.

Personal and Key Transferable/ Employment Skills and Knowledge:

12 Manipulate, integrate and interpret a variety of time series data to arrive at reasoned explanations and predictions.

13 Develop report writing, field notebook keeping and team work skills.

Term 1

Introduction; weathering and soil formation, sediment transport and deposition. Introduction to sedimentary basins

Sediment transport, fluid dynamics and sedimentary structures

Modern sedimentary processes field class (1/2 day)

Sedimentary environments and processes: alluvial to fluvial

Sedimentary environments and processes: aeolian and lacustrine

DORSET FIELDCLASS (including sedimentary basins)

Sedimentary environments and processes: deltaic to shallow marine

Sedimentary environments and processes: shallow marine carbonates

Sedimentary environments and processes: deep water clastics
Sedimentary environments and processes: pelagic

Overview and significance of diagenesis

Term 2
 

Sequence stratigraphy

Downhole geophysical logs (gamma)

Magnetostratigraphy

Sediment provenance

Carbon-isotope stratigraphy

Oxygen-isotope stratigraphy

Cyclostratigraphy and astrochonology

Sr-isotope stratigraphy

Radioisotope dating and timescale

Revision session

As above, 1 to 3 pieces of Coursework (up to 50%), and/or 1 to 2 Exams (25% each).

Basic reading:

ELE – http://vle.exeter.ac.uk/

Other resources:

Gradstein, F. M. et al. 2012, The Geologic Time Scale, 2012, Elsevier

Weedon, G.P., Time-Series Analysis and Cyclostratigraphy: Examining Stratigraphic Records of Environmental Cycles, Cambridge University Press

Rider, M.H., Kennedy, M. 2011, The Geological Interpretation of Well Logs, Rider-French Consulting Limited

Leeder, M.R., 2011, Sedimentology and Sedimentary Basins, Wiley-Blackwell

Nichols, G., 2009. Sedimentology and Stratigraphy, Wiley-Blackwell

Tucker, M.E., 2001, Sedimentary Petrology, 3rd Edition, Wiley-Blackwell

Reading list for this module: