Geophysical Lineaments and Deep Continental Structure

Lineaments may be detected remotely by imaging electromagnetic radiation both inside and outside the visible spectrum and by examining the natural force-fields, particularly the magnetic and gravitational. Most electromagnetic imagery shows shallow structure which is readily correlated with surface geology. Gravimetry and magnetometry may show much deeper structure which is unrelated to surface structure or incompatible with its most obvious downward extrapolation. Seismology then offers scope for the high-resolution study of buried lineaments revealed in this way. From such examinations it is clear than many lineaments do not traverse the entire vertical extent of the lithosphere. Internal horizontal detachment may cause once through-going structures to become segmented. A number of examples will be given, including local Scottish examples: the Great Glen Fault and the Cruachan Lineament.