Sedimentary Basin is a large, three-dimensional depression in the Earth's crust where sediments accumulate to form sedimentary rock

A sedimentary basin is a large, three-dimensional depression in the Earth's crust where sediments accumulate to form sedimentary rock. These basins can be found on land and in the ocean, and are formed by the movement of tectonic plates

1. UNIT - 5 Field Sedimentology, Facies and Environments

2. FIELD SEDIMENTOLOGY A large part of modern sedimentology is the interpretation of sediments and sedimentary rocks in terms of processes of transport and deposition and how they are distributed in space and time in sedimentary environments . To carry out this sort of sedimentological analysis some data are required and this is mainly collected from exposures of rocks.

3. Field equipment Only a few tools are needed for field studies in sedimentology and stratigraphy A notebook to record data is essential A hand lens (10 magnification ) A compass – clinometer A geological hammer . For the collection of samples, small , strong, plastic bags and a marker pen are necessary . A small bottle containing dilute hydrochloric acid is very useful to test for the presence of calcium carbonate in the field Camera A GPS (Global Positioning Satellite) receiver

4. Field studies The organization of a field program of sedimentary studies will depend on the objectives of the project . When an area with sedimentary rock units is mapped the character of the beds exposed in different places is described in terms given below. To describe the lithology the Dunham classification can be used for limestones , and the Pettijohn classification for sandstones . Other features to be noted are bed thicknesses, sedimentary structures, fossils (both body and trace fossils) Rock color and any other characteristics such as weathering, degree of consolidation and so on.

5. Graphic Sedimentary Log A sedimentary log is a graphical method for representing a series of beds of sediments or sedimentary rocks Examples of patterns and symbols used on graphic sedimentary logs