Sedimentary rocks have been the focus of huge amounts of study and billions of research dollars because of their economic importance.

• They house all petroleum reserves, all coal, and most fertiliser.

• Most groundwater sits in sediments or in sedimentary rock.

• They are host to many of the major ore deposits of the world.

• Sand and gravel are used in construction of roads, houses and beaches.

To efficiently and effectively prospect for resources, and to extract and exploit them once found, requires an understanding of the genesis, deposition and petrology of sedimentary rocks. Diagenetic processes especially important for mineral resources.

Fossils are found in sedimentary rocks. Understanding environments of deposition means that we can recreate the environments in which these animals lived and died.

Sediments record conditions at the surface at the time they were deposited. They also provide information about paleogeography: where were the rivers, the shorelines, the mountains.

The mineralogic composition of sediments is a function of weathering, and therefore of climate. In addition, the isotopic composition of some sediments, especially carbonates, is a function of temperature. Analysis of the appropriate sedimentary rocks is the only way of evaluating paleoclimate for times more than 150,000 years ago.

We rely on sedimentary rocks for the interpretation of orogenic belts. The fact that their bedding surfaces approximate a paleohorizontal surface is the key that permits us to recognise and understand the mechanisms and processes of folding and faulting. Their arrangement into stratigraphic packages that are distinct allows us to map displacements and offsets. And the fact that their internal architecture commonly has a bottom and a top lets us recognise when deformation has completely overturned huge pieces of real estate. The cores of orogenic belts, where metamorphism and melting have so transformed the rocks that bedding surfaces and structures are no longer visible, are notoriously difficult to interpret.

Sedimentary rocks are composed of a variety of components, including chunks and fragments of the source rock and chemically precipitated constituents, and weathering products such as clays. Their petrology is in many ways more challenging than igneous or metamorphic petrology because their composition is not goverened by the laws of chemical equilibrium. This first section will look at the composition of sedimentary rocks. Lectures on the different rock types, how they form, and what they are made of; and optical petrology labs interpreting their composition in detail.

Sediment is moved from the source area by means of some transporting agent....wind, water or gravity...and is deposited. Sedimentology involves the study of how particles are moved, and how they are deposited, and how you can retrieve information about the mechanisms and conditions of transport and deposition from stranded sedimentary material or rock. We will have lectures on the principles of fluid flow, sediment transport and the construction of sedimentary deposits. Concurrent labs will deal with flow in modern streams and interpreting sedimentary structures.

Sedimentary deposits are generally concentrated in specific settings: lakes, river valleys, deltas, desert sand seas, deep ocean basins, etc. These environments are characterised by certain processes or sets of processes, and consequently the sediments that are deposited are representative of that environment. This section of the course will look at different depositional settings, and the characteristic processes and products found in each. This topic, based in the study of modern environments, provides the tools which we can use to interpret the paleoenvironments in which sedimentary rocks were deposited. We will have one field lab looking at local fluvial environments, and will use the wave tanks to examine coastal processes.

The characteristics of sedimentary rocks, and of the sedimentary shell of the earth, are outlined in most textbooks.

Although sediments and sedimentary rocks make up only about 11% by volume of the earth's crust, they form a surface mantle which, in addition to forming a layer 0.4 km thick on the ocean floor (Ronov, 1983), covers 65% of the total land area (Blatt, 1975) to an average depth of 4.3 km (Ronov, 1983).