Prospecting for petroleum is a four-step process: 1/ Echo soundings are received. 2/ The soundings are analysed for reflections. 3/ The reflections are interpreted as a geological model. 4/ The prospect is tested by drilling. Seismic data acquisition and analysis in the petroleum industry is a multi-billion dollar activity, Earth Surroundings Analysis describes the elements of soundings analysis. In particular, it examines the relationship between the practical (processing) and theoretical (inversion) approaches to the subject. This new text, together with the author's earlier work - Imaging the Earth's Interior (BSP 1985) provides a complete introduction to geophysical data processing. A primary aim of this text is to explain the process of inverse modelling. Seismologists and exploration geophysicists share the ability to synthesize the data implied by any model. They have much to learn, however, about inverse modelling, that is, given the data, the process of finding the most appropriate model. This new book provides forty computer routines (in Fortran) for data analysis. The author intends to make the text available in an electronic form, where the routines can be used to manipulate real data sets. Exercises at the end of the sections enable the reader to assess his/her grasp of the subject.