Ninetyeast ridge map. 034 Corpus ID: 129716718; Spatial variations of effective elastic thickness over the Ninetyeast Ridge and implications for its structure and tectonic evolution Ninetyeast Ridge is covered by the Bengal Fan north of 5°N. The subduction of the thick, rigid Ninetyeast Ridge changed the geometry and rheology of the eastern Tibetan Plateau lithosphere and asthenosphere Apr 3, 2012 · [1] Analysis of new and existing geophysical data for the Central Indian and Wharton Basins of the Indian Ocean were used to understand the formation and evolution of the Ninetyeast Ridge (NER), especially its relationship to the Kerguelen hot spot and the Wharton spreading ridge. This region has been established to be a complex tectonic structure. Unfortu-nately, such surveys have so far only covered small areas of the ridge [8, 22, 28], whereas, as a whole, its relief is still shown by a satellite map [11]. , 1997). Site ODP758 is located in the northern end of the Ninetyeast Ridge (5 u23 9N, 90 21 E) with 2 925 m of water depth. Nov 1, 2013 · A comparison of age profile along the Ninetyeast Ridge between ODP Sites 758 (82 Ma) and 756 (43 Ma) with similarly aged oceanic crust in the Central Indian Basin and Wharton Basin reveals the Mar 1, 2011 · Research Highlights Dredged glass from the Ninetyeast Ridge (NER) include tholeiitic and alkalic basalt. Basement of the ridge is elevated nearly 2 km with respect to the Bengal Fan; seismic surveys demonstrate continuity of the ridge beneath sediment for 700 km north of 10° N where the ridge plunges below the Fan sediment Jan 31, 2015 · The Ninetyeast Ridge, a linear trace of the Kerguelen hot spot in the Indian Ocean, was emplaced on a rapidly drifting Indian plate. Nov 1, 1991 · Tectonics of the Indo-Australian plate near the Ninetyeast Ridge constrained from marine gravity and magnetic data. t•NINETYEAST TRENCH BROKEN RIDGE 212 io' 755 Figure 1. However Drilling Program Site 1107, Ninetyeast Ridge, from implosive bottom sources and airgun shots Ingo Grevemeyer and Ernst R. Gravity anomalies and deep structure of the Ninetyeast Ridge north of the equator, eastern Indian Ocean-a hot spot trace model [J]. General bathymetric map of the northeastern Indian Ocean [Fisher et al. …. Here, an outcrop basement located at the middle of the seismic line presents Jan 1, 2007 · In addition, stretches of the Ninetyeast Ridge and oceanic crust in adjacent basins evolved during the contemporaneous ages between 77 and 43 Ma suggest that the ridge was accreted at a rate of Ninetyeast Ridge since 3. of the ridge is bordered by a fracture zone and In a broader sense, when large earthquakes, a complex of ridges and grabenlike troughs over a longer period of time, are considered, the approximately parallel to the ridge [Bowin, Ninetyeast Ridge is not aseismic but a rather 1973]. Until now, ideas about its magnetic Oct 12, 2014 · The NinetyEast Ridge (NER), one of the most enigmatic features in the Indian Ocean, is covered by thick Bengal Fan sediment north of 9°N. It is 200 km wide on average, and it Oct 2, 2013 · Residual Mantle Bouguer Anomaly (RMBA) map of the NER and adjacent basins reveals that the entire length of the NER is associated with a significant negative anomaly up to 200 mGal, indicating the presence of thickened crust or less dense mantle beneath the ridge. Oct 1, 2013 · The Ninetyeast Ridge (NER), a north–south striking, 5,000km long, 77 to 43Ma chain of basaltic submarine volcanoes in the eastern Indian Ocean formed as a hotspot track created by rapid Mar 12, 2020 · Abstract— The comprehensive analysis of geological, geophysical, and geochemical data makes it possible to obtain the most complete picture of the geological structure of the central part of the Ninety East Ridge (NER), the Osborn Plateau, and the adjacent part of the Central Basin. Satellite gravity data and magnetic anomalies 34 through 19 Sep 1, 2010 · The Ninetyeast Ridge (Figure 4b; Frey et al. 2 km/s and V s ∼ 2. The 5000-km-long ridge, from lat 34°S to Rat 10°N, was drilled at three sites during Leg 121. Aug 25, 2020 · Mukhopadhyay M, Krishna M B R. Oblique subduction and the buoyancy forces arising from subduction of the NER render the subduction processes near the Andaman arc highly Dec 12, 2017 · The model indicates that the Ninetyeast Ridge was created by volcanism along the ridge axis between the Indian and Australian Plates, while the Kerguelen plume was located farther away underneath the Australian plate. We present seismic reflection data on the eastern flank of the NER, at 10°N, that show the presence of 4–5 km thick sediments beneath the Bengal Fan sediments. It was coined by Tharp and Heezen when compiling their physiographic diagram of Indian Ocean (early 1960s), based on early indications from RIMS Fisheries cruises and HMS "Challenger" (1951-1952). doi: 10. , 1989; Royer et al. Shaded areas around the NER represent diffuse plate boundaries (I-C = India-Capricorn, C-A = Capricorn-Australia, I-A = India-Australia; DTJ = diffuse triple junction) [Royer and Gordon, 1997]. Xudong Xu 1,2,3, Jianguo Liu 1,2,4,*, Yun Huang 1,*, Lanlan Zhang 1,2, Apr 26, 2023 · The linear Ninetyeast Ridge (NER) is the longest oceanic intraplate volcanic edifice and main feature in the Eastern Indian Ocean. The effective elastic Figure 7. 7) and 10 magnitude 6 events have occurred in this general area. Bathymetry, geoid, and gravity (shipborne and satellite) data along 72 closely spaced transects and 17 overlapping grids on the NER are analyzed and modeled to determine Mar 31, 2016 · The study of magmatism and tectonic structure of the East Indian or Ninetyeast Ridge (NER) reveals the geochemical similarity of mantle sources for the NER and Kerguelen Plateau melts. , 2015) and to cause summer temperature and moisture fluctuations in southwestern China during the last deglaciation (Zhang et May 17, 2013 · The white circles on the Ninetyeast Ridge are the DSDP Legs 22 and 26 drill site (216, 214, 253 and 254) locations where basement was recovered, and the white stars are the ODP leg 121 drill site of the Ninetyeast Ridge and their tectonic significance K. Since 1913, 4 magnitude 7 or greater earthquakes (including one with M s = 7. Feb 16, 2018 · Cenozoic adakitic rocks in the Gangdese changed from barren continental melts to ore-forming slab melts at ~ 23 Ma. Squares are Ninetyeast Ridge (NER), one of the longest linear volcanic features on the Earth, offers an excellent opportunity of understanding the isostatic response to the interactions of mantle plume with the migrating mid-ocean ridge. Coordinates in ACUF (en): Latitude: -4; Longitude: 90. 1989 Dec 11, 2002 · The Ninetyeast Ridge is a major aseismic ridge that extends nearly meridionally for approximately 5000 km from the Ba y of Bengal in the north to Broken Ridge in the south (Fig. , 1982]. 2002). Some high MgO (> 9. However, a markedly low strength (0 < T e < 3 km) in that region, where the NER is close to the Andaman trench (north of 10°N), receives our main Jul 1, 2001 · These data were used to prepare a sediment isopach map of the study area. The distribution and chemical characteristics of the ore-forming adakites point to an association with the Ninetyeast Ridge. [1] The Ninetyeast Ridge (NER), one of the longest linear volcanic features on the Earth, Apr 30, 2014 · New multibeam bathymetry data and multichannel seismic profiles over 7 detailed survey sites collected during cruise no. About 178 m of basalt, >38 to >80 Ma, were recovered from a total penetration of ˜310 m. Please refer to Fig. The region also includes aseismic ridges of 85?E, Broken and Comorin Keywords Indian Ocean; Ninetyeast Ridge; Indo-Australian plate; plate tectonics; marine geophysics 1 Introduction The tectonic activities on the Indo-Australian plate (IAP) near the Ninetyeast Ridge (NER) are complex be- cause this area is surrounded by all the three types of plate boundaries: subducting trench to the east and north, Nov 26, 2013 · Here we present high resolution maps of the lithosphere's effective elastic thickness over the exposed section (between 10°N and 30°S) of the Ninetyeast Ridge (NER), in order to understand its temporal evolution based on variations in the thermo-mechanically- and compositionally-controlled strength of the lithosphere. The positive anomalies are bordered by belts of negative anomalies. It is named for its extraordinary geographical position. These islands lie atop the Kerguelen Plateau, which also originated from volcanism at this hot spot. Bathymetric contours of 4000, 3000, and 2000 m are also drawn using gridded bathymetry from Smith and Sandwell [1997] . Introduction The Ninetyeast Ridge (NER) in the eastern Indian Feb 1, 2008 · The convergence tectonics of the Ninetyeast Ridge (NER), upon the Andaman island arc–trench system is examined through an analysis of ETOPO2 bathymetry, satellite-derived free air gravity and seismic data. In respect of the revealed structural The Ninety East Ridge. 5 Ma BP from the core of hole ODP758 in the Ninetyeast Ridge of the Indian Ocean. MAGNETICS No pattern to the regional magnetic anomalies over the Ninetyeast Ridge has yet been discerned. 28–0. 1007/BF01203426 The east side maps. Based on these data,it discusses the manifestations and related mechanisms of such major tectonic and environmental events as the rapid uplift of Jun 1, 2001 · The structural model of the Ninetyeast Ridge in the eastern Indian Ocean derived from seismic and gravity results presents an explicit geological process that underwent when the Kerguelen plume Jan 31, 2015 · The Ninetyeast Ridge, a linear trace of the Kerguelen hot spot in the Indian Ocean, was emplaced on a rapidly drifting Indian plate. Ninetyeast Ridge is joined at its southern end to Broken Ridge, which is oriented N90°E. Mar 1, 2014 · Right: structural map, insets show detailed fragments with rightt lateral strikeeslip faults. (a) Location of the Ninetyeast Ridge and surrounding eastern Indian Ocean (red window, used for T e and Moho depth Feb 28, 2013 · The Ninetyeast Ridge rises to a maximum height of ∼3·5 km above the surrounding ocean floor (Fig. Schematic map of the southern Ninetyeast Ridge/Broken Ridge area during the Late Cretaceous-Paleocene illustrates a possible explanation for the longevity of the basaltic ash eruptions recorded at Broken Ridge (Sites 752 through 755). A number of climate forcings trigger the changes of the Indian summer monsoon (ISM) precipitation centroid, while the ISM rainfall projected by climate models shows a large discrepancy in local precipitation patterns. We have determined the mechanisms of several of these earthquakes, which suggest that the bottom topography of the Ninetyeast Ridge. , 2011;Müller, Royer, & Lawver, 1993;Royer, Peirce, & Weissel, 1991), one of the longest linear bathymetric features on the Earth, extends for more Sep 1, 2015 · For the Ninetyeast Ridge, based on major/trace element and isotopic geochemistry, Frey et al. Here, we use clay minerals and Sr–Nd isotopes obtained from a gravity core on the Ninetyeast Ridge to track the corresponding Oct 8, 2010 · The total crust map obtained after subtracting the water and sediment layers from the Moho depth map shows an unusually thin oceanic crust of 2–4 km in the deep basinal areas of BOB and 10–12 km of thick crust below 85° E and Ninetyeast ridges. These observations, combined with other geophysical data, show that the Ridge is primarily a sunken oceanic island and seamount chain. Background plot is satellite-predicted bathymetry [Smith and Sandwell, 1997]. 1). May 1, 1992 · Palaeomagnetic results from a lower Turonian to Middle Eocene ash-rich sedimentary sequence on Broken Ridge (ODP Sites 752–755) and ash and basalt sequences on Ninetyeast Ridge (90ER) (Sites 756–758) (1) support a Kerguelen hotspot origin for the 90ER volcanic pile; (2) are consistent with models for a large-scale southward jump of the Southeast Indian Ridge (SEIR) west of the 90ER at We present 2‐D Vp and Vs models using wide‐angle seismic data at the Indian basin adjacent to the NinetyEast Ridge. Here, we use clay minerals and Sr–Nd isotopes obtained from a gravity core on the Ninetyeast Ridge to track the corresponding Nov 26, 2013 · DOI: 10. 1983). Additional complexities are created by partial subduction of the ridge below the Andaman Trench that locally modifies the arc-trench gravity field. Int For this reason, the Ocean Drilling Program (ODP) and the International Ocean Discovery Pro-gram (IODP) drilled the Ninetyeast Ridge (NER) where the ridge-top location of the NER has prevented the turbiditic sediment input and the resultant truncation of the underlying sequence: ODP Site 758 and IODP Site U1443 (5° 23. The Ninetyeast Ridge, far from being ‘aseismic’, has historically been a region of substantial seismicity. . Major variations in This paper examines the constraints on the tectonic setting of Ninetyeast Ridge, based on a compilation of bathymetric and magnetic data from the basins surrounding Ninetyeast Ridge in the Indian Ocean that includes the magnetic profiles collected under way during ODP Leg 121. Red and green lines show gradient lineations on the Ninetyeast Ridge; the latter color shows those confirmed by seismic and/or bathymetry data from cruise KNOX06RR. Magma production rates along the ridge track are computed using gravity-derived excess crustal thickness data. Jan 1, 1991 · The 5000-km-long ridge, from lat 34°S to Rat 10°N, was drilled at three sites during Leg 121. However, detailed study of the magma production rates along SREEJITH AND KRISHNA Dec 1, 1999 · A comparison of age profile along the Ninetyeast Ridge between ODP Sites 758 (82 Ma) and 756 (43 Ma) with similarly aged oceanic crust in the Central Indian Basin and Wharton Basin reveals the Mar 8, 2023 · We present 2‐D Vp and Vs models using wide‐angle seismic data at the Indian basin adjacent to the NinetyEast Ridge. Carbonate sedimentary caps on these seamounts prevent their direct geological sampling by dredging, therefore indirect Oct 9, 2008 · A 550-km-long transect across the Ninetyeast Ridge, a major Indian ocean hotspot trail, provided seismic refraction and wide-angle reflection data recorded on 60 ocean bottom instruments. Magmas related to the Kerguelen plume were derived from an enriched mantle source, whereas the NER tholeiitic basalts originated from a source contaminated by a depleted material. The hypothesis that hotspots are the sources of many continental flood basalts is evaluated geochemically for the proposed Rajmahal Traps–Ninetyeast Ridge–Kerguelen hotspot system. 2 Method This paper discusses paleocean, paleoclimate and paleoenvironment characteristics at site ODP758 in the Ninetyeast Indian Ocean. Jun 28, 2021 · Geophysical data indicate strong lateral and deep heterogeneity of the Ninetyeast Ridge, which is roughly divided into three segments based on its morphology, style of tectonic deformation of its sedimentary cover, and the deep structure of the crust beneath it: northern, central, and southern. Marine Geophysical Researches, 1995, 17(2): 201-216. Many seamounts are located on the ridge, whose origin and age Nov 18, 2021 · Abstract. 2 for legend. Ninetyeast Ridge (Talwani and Kahle, in press). Although the Indo-Australian plate near the Ninetyeast Ridge is important for understanding the formation of new plate boundaries, its tectonic problems are complex and most of them are poorly known. While, depleted basalt Feb 20, 2003 · Satellite-derived free -air anomaly map of the surrounding area of Ninety-East Ridge [Andersen and Knudsen, 1998]. , Mahoney et al. 3 km/s). The geochemical/isotopic similarities are convincing and their formation by action of the Kerguelen Hotspot activity seems very probable (Weis et al. J. Bathymetry 1000-4000 m contours are shown. 4) The Ninetyeast Ridge was formed in more southerly latitudes and has since been transported northwards. The ridge is about 2-3 km above the adjacent seafloor and its width varies from 150 to 250 km. Satellite gravity data and magnetic anomalies 34 through 19 define crustal isochrons and show fracture zones Aug 7, 2020 · The Ninetyeast Ridge (NER) is a world’s largest aseismic ridge formed by a hotspot trail of the Kerguelen mantle plume that presently lies beneath the northwest part of the Kerguelen Plateau (Coffin and Eldholm 1992; Coffin et al. Jul 7, 2022 · A connection between the Rajmahal Traps, the Ninetyeast Ridge, and (sections) of the southern Indian Ocean, around the island of Kerguelen, has been made for decades (e. model, the Ninetyeast Ridge is a long-lived, deep-seated, magmatically active near-fault ridge on a plane-tary scale associated with a transform fault separating two large oceanic plates [15]. This differs with previous studies that described the Ninetyeast Ridge as the result of the Indian Plate moving above the plume. Apr 1, 2012 · [1] Analysis of new and existing geophysical data for the Central Indian and Wharton Basins of the Indian Ocean were used to understand the formation and evolution of the Ninetyeast Ridge (NER), especially its relationship to the Kerguelen hot spot and the Wharton spreading ridge. pensation of the ridge at the base of the crust. The Ninetyeast Ridge is an 5500 km long, north^south-oriented, submarine volcanic ridge in the eastern Indian Ocean that formed from magmatism associated with the deep-seated Kerguelen mantle rates of the Kerguelen Plateau, Broken Ridge, Ninetyeast Ridge, and associated Cretaceous magmatism found near the continental margins of India, Australia, and Antarctica and provided a rough estimation of 0. This applies to an even greater extent to studying the Ninetyeast Ridge’s magnetic anomaly. The ridge comprises a linear volcanic rise stretching approximately 5000 km along the 90° E meridian Feb 1, 2008 · The convergence tectonics of the Ninetyeast Ridge (NER), upon the Andaman island arc–trench system is examined through an analysis of ETOPO2 bathymetry, satellite-derived free air gravity and Mar 1, 2016 · The study of magmatism and tectonic structure of the East Indian or Ninetyeast Ridge (NER) reveals the geochemical similarity of mantle sources for the NER and Kerguelen Plateau melts. Major variations in Jul 1, 2010 · Location Deep Sea Drilling Program Leg 22, Site 214 on the Ninetyeast Ridge (NER) in the mid‐Indian Ocean region. May 30, 2010 · The northern Ninetyeast Ridge system has totally vanished from the z = 300 km height free-air gravity anomaly map, thus indicating the apparent low density observation at this portion of the ridge from previous height—continued anomalies that are dominated by the crustal contribution, rather than that driven by the mantle lithosphere. 67′ E Here we present high resolution maps of the lithosphere's effective elastic thickness over the exposed section (between 10°N and 30°S) of the Ninetyeast Ridge (NER), in order to understand its temporal evolution based on variations in the thermo-mechanically- and compositionally-controlled strength of the lithosphere. While, depleted basalt Nov 18, 2021 · An Intertropical Convergence Zone shift controlled the te rrestrial material supply on the Ninetyeast Ridge 1 . along the Ninetyeast Ridge hotspot trail,” Geophys. Here, an outcrop basement located at the middle of the seismic line presents The Ninetyeast Ridge north of the equator in the eastern Indian Ocean is actively deforming as evidenced by seismicity and its eastward subduction below the Andaman Trench. Ninetyeast Ridge reveal anomalous basalt composi- tions and symmetrical age distribution around 15~ latitude. Sreejith1 and K. Near 15°S, a circular topographic rise with a radius of ∼150 km (Osborn Knoll The NinetyEast Ridge (NER) holds a unique position among global tectonic features and represents one of the problematic structures of not only the Indian Ocean but the World Ocean in general. The production rates change between 2 and 15 m 3 /s over timescales of 3–16 Myr. Krishna2 Received 16 January 2013; revised 12 September 2013; accepted 23 September 2013; published 15 October 2013. It is 1 000 m higher than the Bengal Fan. Analysis of new and existing geophysical data for the Central Indian and Wharton Basins of the Indian Ocean were used to understand the formation and evolution of the Ninetyeast Ridge (NER), especially its relationship to the Kerguelen hot spot and the Wharton spreading ridge. This 'cushion' is up to 8 km thick and 400-600 km wide. Here, an outcrop basement located at the middle of the seismic line presents uppermost crustal Poisson's ratios ( ν ) of 0. Flueh Location map showing the layout of the experi- ment. Broken Ridge and the Kerguelen Pla-teau are a conjugate pair of tectonic features that were separated by Eocene rifting and subsequent seafloor spreading along the Southeast Indian Ridge. M. NINETYEAST RIDGE, EQUATORIAL INDIAN OCEAN1 Bhoopal R. Apr 1, 1999 · On Ninetyeast Ridge the seismological community drilled Ocean Drilling Program (ODP) Site 1107, coincident with ODP Site 757, for the future host of a long-term seismological observatory in the Feb 28, 2015 · The Ninetyeast Ridge (NER), a linear trace of the Kerguelen hot spot in the Indian Ocean, was emplaced on a rapidly drifting Indian plate. 1016/J. Many seamounts are located on the ridge, whose origin and age remain unclear due to the lack of samples of the bedrock of which they are composed. g. Jan 21, 2022 · The long-term evolution of the South Asian monsoon system and its influence on the Bay of Bengal (BOB) is of great interest to climate scientists. Mar 1, 2021 · Abstrac t — The Ninetyeast Ridge is the longest linear intraplate rise in the World Ocean and the main tectonic and magmatic feature in the East Indian Ocean. Download : Download high-res image (470KB) Download : Download full-size image; Fig. S. 29 ( V p ∼ 4. , 1991). 3-D crustal thickness map of the NER, generated by inversion of the RMBA data Jun 22, 2022 · Abstract. Magma production rates along the ridge track are computed Sep 1, 2010 · The Ninetyeast (or East Indian) Ridge is one of the longest aseismic volcanic ridges in the World Ocean and one of the longest linear structures of the Earth. Circle shows E–W lineation caused by trough in Figure 2d. 1b) and has an average width of 200 km, except for an ∼700 km segment south of ∼7°S, where it is ∼100 km wide (Peirce et al. Naini and Stephen L. 5%) NER glasses are partial melts of garnet lherzolite. Sep 9, 2010 · (b) Satellite gravity vertical gradient map. 1. (2011 Frey et al. 2013. , 2018) since the shift in the ITCZ was considered to control rainfall distribution and intensity in central India over geological timescales (Zorzi et al. TECTO. Such glasses formed over a large pressure range ~ 3 to < 1 GPa. Boxes on the Ninetyeast Ridge are locations of polygons I and II, in which closely spaced geophysical profiles, including seismic reflection and refraction, were Jun 22, 2022 · Ninetyeast Ridge to track the corresponding source varia-tions and analyze the relationship between terrestrial mate- Map showing dispersal patterns of the BoB clay minerals for core 17I106. Dec 15, 2013 · The major structure on the India plate, the Ninetyeast Ridge (NER), exhibits a weak mechanical strength, which is consistent with the expected signature of an oceanic ridge of hotspot origin. Due to the widespread nature of observed thin crust as well as the presence of plume traces that An ITCZ shift on the Ninetyeast Ridge et al. Basalt compositions are consistent with the NER forming as a hotspot track. They allow making a step forward in interpreting the nature of the Aug 8, 2013 · Ninetyeast Ridge environs and tectonic setting. Ideas about the nature and Additional information (en): Correct spelling of this name is one word "Ninetyeast". Eittreim, Lamont-Doherty Geological Observatory, Columbia University, Palisades, New York ABSTRACT This study has revealed that the Ninetyeast Ridge at this location is made up of linear north-south-trending topography with isolated highs on the crest. (c) Tectonic elements interpreted on gravity gradient. , 2013; Weber et al. Environmental Science, Geology. Feb 1, 1991 · Data and observation from Drifting Program Leg 121 and plate-tectonic reconstructions indicate that the Ninetyeast Ridge (Indian Ocean) was derived from the interaction of a deep-seated Dupal hotspot and a nearby spreading-ridge axis. However, adherents of the purely tectonic nature of the Ninetyeast Ridge still remain, including the most exotic models, where the Apr 1, 2016 · A reconnaissance survey of Fe–Mn crusts from the 5000 km long (~31°S to 10°N) Ninetyeast Ridge (NER) in the Indian Ocean shows their widespread occurrence along the ridge as well as with water depth on the ridge flanks. It appears that the Kerguelen hotspot did not directly feed Rajmahal magmas, although it may The study of magmatism and tectonic structure of the East Indian or Ninetyeast Ridge (NER) reveals the geochemical similarity of mantle sources for the NER and Kerguelen Plateau melts. No NER samples are compositionally similar to mid-ocean ridge basalt. Download : Download full-size image; Fig. ( , 2015 argued three major source components must be present in the mantle: (1) a Sep 15, 2015 · The Ninetyeast Ridge (NER) in the Eastern Indian Ocean is a 5000 km long chain of submarine volcanoes ranging in age from 77 Ma at ODP Drill Site 758, where the NER is covered by Bengal Fan sediments, to 43 Ma at ODP Drill Site 254, near Broken Ridge that was separated from the Kerguelen Plateau by formation of the Southeast Indian Ridge (Fig. 5 Ma. Reconstructions based on a fixed hot spot assumption demonstrate strong support for this point source model. The crusts are hydrogenetic based in growth rates and discrimination plots. Geothermal structure map of the Ninety-East and Chagos-Laccadive Ridges and adjoining areas of the Indian Ocean. The southward ridge jumps off spreading center beneath the Ninetyeast Ridge (Krishna et al 1995) and its interactions with the Kerguelen hotspot add a more complicated tectonic history for the Nine- The paper presents the pelagic records of planktic foraminifera,as well as the data of lithostratigraphy,stable isotope stratigraphy and carbonate stratigraphy since 3. Moreover, the continuous Nov 26, 2013 · The elevation of the ridge ranges from 2 km in the south to 3 km in the north, and north of 10°N it is buried under a thick pile of Bengal Fan sediments (Gopala Rao et al. 1 km3/yr (3. 2 m3/s) magma flux for the entire NER track. In the basin west of the ridge the east-west-trending sea-floor spreading anomalies (anomalies 23-30) approximately between 2°S Apr 1, 2003 · The ridge is connected at an approximate right angle by the Broken Ridge at about 30° S. The Ninetyeast Ridge is thought to have originated from hot spot volcanic activity now located at the Kerguelen Islands near Antarctica. KNOXRR06 of the R/V Rodger Revelle in 2007 fundamentally expanded the concepts about the structure of the sedimentary cover of the Ninety-East Ridge, which were based on the results of previous studies. The Ninety-East Ridge (NER) is 5000 km long linear bathymetric feature striking more or less paralle to the 90°E meridian from south of Broken Ridge (at ~31°S), southwest of Australia, north to the Bay of Bengal, east of India. 07. Shipboard Published in Nature 1 June 1983. Magnetic data in the Central Indian Basin demonstrate that the spreading center immediately west of Ninetyeast Ridge Jan 30, 2008 · East of Ninetyeast Ridge in the Wharton Basin, anomalies 19 through 27, with spreading rates varying in concert with those of comparable age west of the ridge, have been found to increase in age Mar 1, 2003 · The linear Ninetyeast Ridge (NER) is the longest oceanic intraplate volcanic edifice and main feature in the Eastern Indian Ocean. Among various climate drivers, direct evidence for the Intertropical Convergence Zone (ITCZ) control of sediment supply on the millennial scale is lacking, and the changes in ITCZ migration demonstrated in paleoclimate records need to be better investigated. 05′ N, 90° 21. Maps of the central Indian Ocean region showing the positions of Site 214 May 1, 2014 · General bathymetry map of the eastern Indian Ocean showing location of the Ninetyeast Ridge between 34?S and 10?N latitudes. Flexural bulge of the 85° E Ridge and subsidence of the Ninetyeast Ridge about 24 cm my−1 rate since early Eocene Feb 27, 2023 · We present 2-D V p and V s models using wide-angle seismic data at the Indian basin adjacent to the NinetyEast Ridge. cz cz yb fh ib ps be of sh ee