georefid:2003-003460SEDIS Publication Catalogueana.macario@awi.dehttp://sedis.iodp.org/pub-catalogue/informationpointOfContact2011-06-23T00:00:00Zhttp://sedis.iodp.org/pub-catalogue/index.php?id=2003-003460<gco:CharacterString>Formation of diapiric structure in the deformation zone, central Indian Ocean; a model from gravity and seismic reflection data</gco:CharacterString>2002-01-01publicationgeorefid:2003-003460Krishna, K. S.National Institute of Oceanography, Goa, IndiaauthorGopala Rao, D.P. P. Shirshov Institute of Oceanology, Russian FederationauthorNeprochnov, Yu. P.authorIndian Academy of Sciences, Bangalore, IndiapublisherdocumentHardcopyProceedings of the Indian Academy of Sciences: Earth and Planetary Sciences111 (1)17-28Analyses of bathymetry, gravity and seismic reflection data of the diffusive plate boundary in the central Indian Ocean reveal a new kind of deformed structure besides the well-reported structures of long-wavelength anticlinal basement rises and high-angle reverse faults. The structure (basement trough) has a length of about 150 km and deepens by up to 1 km from its regional trend (northward dipping). The basement trough includes a rise at its center with a height of about 1.5 km. The rise is about 10km wide with rounded upper surface and bounded by vertical faults. A broad free-air gravity low of about 20 m Gal and a local high of 8 m Gal in its center are associated with the identified basement trough and rise structure respectively. Seismic results reveal that the horizontal crustal compression prevailing in the diffusive plate boundary might have formed the basement trough possibly in early Pliocene time. Differential loading stresses have been generated from unequal crust/sediment thickness on lower crustal and upper mantle rocks. A thin semi-ductile serpentinite layer existing near the base of the crust that is interpreted to have been formed at mid-ocean ridge and become part of the lithosphere, may have responded to the downward loading stresses generated by the sediments and crustal rocks to inject the serpentinites into the overlying strata to form a classic diapiric structure.completedSolid-earth geophysicsAustralian PlateBengal FanCenozoicDeep Sea Drilling ProjectdeformationdiapirsDSDP Site 215DSDP Site 218geophysical methodsgravity methodsIndian OceanIndian PlateLeg 22Ninetyeast Ridgepaleogeographyplate boundariesplate tectonicsplatesreflection methodsseismic methodsTertiaryurn:org.iodp:exp:22urnlargerWorkCitationcampaignurn:org.iodp:exp:22:site:215urnlargerWorkCitationstudyurn:org.iodp:exp:22urnlargerWorkCitationcampaignurn:org.iodp:exp:22:site:218urnlargerWorkCitationstudyurn:org.iodp:exp:22urnlargerWorkCitationcampaignEnglishgeoscientificInformation86.165886.4730-8.07188.0026