This brief introductory textbook fills a definite need. There have been no accessible references in Spanish on general geophysics. The level of the book requires only a knowledge of high school physics, according to the preface; however, this is not so much a high school text as a reference guide for the general reader.

The book contains four chapters: (1) Gravity and the Shape of the Earth, (2) Earthquakes and the Interior of the Earth, (3) The Magnetic field, and (4) Origins and Evolution of the Earth. The latter chapter contains most of the relevant information on plate tectonics and dynamics of the lithosphere. The sequence of chapters is somewhat awkward, since the idea of lithospheric plates is already introduced in Chapter 2. In fact, the discussion of plate tectonics contains several inconsistencies: in Figure 4-4, for example, volcanoes are shown as plumes rising from the Benioff zone and erupting offshore, on the continental slope. The text compounds the confusion: ‘Because of the dip angle of the sinking plate, these volcanoes are found behind the coast line. Continental rocks in the collision zone are pushed up to form large mountain ranges in some places, such as the Andes.’