Understanding the moho and the lithosphere-asthenosphere boundaries
Too deep to see or reach via drilling, the Moho (crust-mantle transition) remains something of a mystery more than a hundred years after its discovery. This insightful, multidisciplinary volume includes studies from Antarctica, Australia, Morocco, the eastern United States, the Canadian Cordillera, India, Ethiopia, South Africa, and Italy.
Volume editor Gianluca Bianchini (Università di Ferrara) and colleagues explain, "These studies indicate that the geophysical Moho is not a simple feature, with variations at different scale lengths that preclude a single, universally applicable interpretation. A key challenge is to unravel the structural relationship between the lower crust and underlying lithospheric mantle."
Additionally, they note, "At greater depths, the lithosphere-asthenosphere boundary (LAB) represents a first-order structural discontinuity that accommodates differential motion between the tectonic plates and the underlying mantle. This boundary is also irregular and the detection of its location and morphology is complex. For this reason, the seismic proxies must be complemented by petrological investigations of mantle-derived melts and exhumed mantle xenoliths in order to constrain the physical and chemical gradients across the LAB that create differences in mechanical strength."
More information:
Individual copies of the volume may be purchased through The Geological Society of America online store, rock.geosociety.org/Store/detail.aspx?id=SPE526, or by contacting GSA Sales and Service, gsaservice@geosociety.org.
Provided by Geological Society of America
