Chapter 5

Getting under the skin of the Earth

McKenzie, JacksonJacksonJames Jackson (1954-present) of the University of Cambridge works on active deformation of the continents, focusing on earthquake source seismology alongside geomorphology, space geodesy and remote sensing. He is interested in quantifying not only the deformation from individual fault ruptures but also in how individual earthquakes combine to produce the landscape of active tectonic regions. and PriestleyPriestleyKeith Priestley (1946-present) of the University of Cambridge is a seismologist with an interest in the structure and mechanical behaviour of the continents. He combines comprehensive seismological information with geochemistry, petrology and mineral physics to delve into the fundamental processes that shape the Earth. (2005) continues to consider the implications of the distribution of earthquakes, this time in terms of the thermal structure of the lithosphere. The authors find that mantle earthquakes take place almost exclusively in material at less than 600°C; exceptions arise at high strain rates. They find no convincing evidence that ocean and continental lithosphere behave differently. Composition does not affect their rheologyrheologythe scientific study of the flow of matter. ; temperature is the key. The paper also re-examines the 1967 model of ocean lithosphere cooling, which stands up well to analysis nearly 40 years later, with better mineral physics data.