The Holocene record on the coasts of the Arabian Sea provides information on the nature and rate of deformation generated by the interaction between the Indian, Arabian and Eurasian Plates. Holocene marine terraces show that the southern Makran has been subject to the infrequent but vigorous coseismic uplift (蠄2 m) that characterizes other subduction settings and they indicate landward rotation of the imbricate faults among which shortening is distributed. The lack of significant Holocene deformation on the SE coast of the Arabian peninsula is consistent with its position parallel to a transform, although there is evidence for large-scale buckling driven by convergence at the Strait of Hormuz in the NE. Geomorpholo-gical and tide-gauge evidence for localized uplift on the southwestern coast of India may represent compressional buckling here too in response to Himalayan collision. Bathymetric and geodetic data can help to bridge these sequences and thus enhance their value for quantifying plate rheology and dynamics, notably by linking variations in plate-margin displacement with major sea-floor strike-slip structures and by eventually confirming transitory as well as sustained compressive buckling on land.
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The Tectonic and Climatic Evolution of the Arabian Sea Region
Over long periods of time the tectonic evolution of the solid Earth has been recognized as the major control on the development of the global climate system. Tectonic activity acts in one of two different ways to influence regional and global climate: (i) through the opening and closing of oceanic gateways and its effect on the circulation patterns in the global ocean; (ii) through the growth and erosion of orogenic belts, resulting in changes in oceanic chemistry and disruption of atmospheric circulation. The Arabian Sea region has several features that make it the best area for studies of climate and palaeoceanographic responses to tectonic activity, most notably in the context of the South Asian monsoon and its relationship to the growth of high topography in the adjacent Himalayas and Tibet.
The Tectonic and Climatic Evolution of the Arabian Sea Region brings together a collection of recent studies on the area from a wide group of international contributors. The paper range from high resolution, Holocene palaeoceanographic studies of the Pakistan margin to regional tectonic reconstructions of the ocean basin and surrounding margins throughout the Cenozoic. Marine geophysics, stratigraphy, isotope chemistry and neotectonics come together in a multidisciplinary approach to the study of interactions of land and sea. while much work remains to be done to understand fully the tectonic and climatic evolution of the Arabian Sea, a great deal has been achieved since the last major review, as detailed in the 26 contributions. This volume is essential reading for palaeoceanographers, sedimentologists and geophysicists. It will also be interest to structural geologists and those working in the petroleum industry.