First Break - Volume 11, Issue 1, 1993

Coal is a sediment consisting largely of carbonaceous material derived from plants, deposited in horizontal layers between other shallow water clastics. Upon burial ,the entire section is compressed, losing water and undergoing systematic alteration. The extent of the alteration is determined by maximum temperature and pressure, and the duration of burial. The increasing levels of alteration are evident from increasing hard ness and lustre, and decreasing porosity andvolatile content, grading from peat through lignite, bituminous coal and then anthracite.

In recent years 3D seismic techniques have acquired an increasing importance in field appraisal and development. The advantages obtained, in terms of greater knowledge of the geological setting, greater accuracy in field development and the increased rate of success, have spurred oil companies to move quickly towards 3D exploration surveys, in spite of the considerable investments involved.