Seismic exploration

Abstract

Of all the geophysical exploration methods, seismic surveying is unequivocally the most important, primarily because it is capable of detecting large-scale to small-scale subsurface features. Simply stated, seismic methods involve estimation of the shapes and physical properties of Earth’s subsurface layers from the returns of sound waves that are propagated through the Earth. Early wildcatters found oil by drilling natural oil seeps and large folds (anticlines) in exposed rocks. These easy oil prospects were all quickly discovered and drilled, and geologists then turned to seismic surveys to find less obvious oil and gas traps. Seismic technology had been used since the early 1900s to measure water depths and detect icebergs, and by 1924, seismic data were first used in the discovery of a Texan oil field (Milligan 2004). Several introductory and advanced textbooks (e.g., Telford et al. 1990, Sheriffand Geldart 1995, Yilmaz 2001) describe the principles of acquisition, processing and interpretation of seismic data. This chapter reviews the fundamental concepts employed in seismic exploration.