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Curray, JR.  2014.  The Bengal Depositional System: From rift to orogeny. Marine Geology. 352:59-69.   10.1016/j.margeo.2014.02.001   AbstractWebsite

The Bengal Depositional System is defined as the surface depositional environments and the underlying sediment accumulation extending from the alluvial, lacustrine and paludal sediments of the lower Ganges and Brahmaputra Rivers, across the Bengal Delta, the Bangladesh continental shelf and slope to and including the Bengal Fan. Together it is one of the greatest sediment accumulations in the modern world, and is comparable in volume to the great sediment accumulations of the geological past. The history of formation started with the Mesozoic breakup of Eastern Gondwanaland, the northward drift of India, its collision with the southern margin of Asia, rotation and bending of the western Sunda Arc, and the penetration of the Indian continental mass into southern Asia. During this history, the regional tectonics evolved and sources and provenance of the sediments changed with the ultimate uplift of the Tibetan Plateau and the Himalayas. (C) 2014 Elsevier B.V. All rights reserved.

Curray, JR.  2005.  Tectonics and history of the Andaman Sea region. Journal of Asian Earth Sciences. 25:187-228.   10.1016/j.jseaes.2004.09.001   AbstractWebsite

The Andaman Sea is an active backarc basin lying above and behind the Sunda subduction zone where convergence between the overriding Southeast Asian plate and the subducting Australian plate is highly oblique. The effect of the oblique convergence has been formation of a sliver plate between the subduction zone and a complex right-lateral fault system. The late Paleocene collision of Greater India and Asia with approximately normal convergence started clockwise rotation and bending of the northern and western Sunda Arc. The initial sliver fault, which probably started in the Eocene, extended through the outer arc ridge offshore from Sumatra, through the present region of the Andaman Sea into the Sagaing Fault. With more oblique convergence due to the rotation, the rate of strike-slip motion increased and a series of extensional basins opened obliquely by the combination of backarc extension and the strike-slip motion. These basins in sequence are the Mergui Basin starting at similar to 32 Ma, the conjoined Alcock and Sewell Rises starting at similar to 23 Ma, East Basin separating the rises from the foot of the continental slope starting at similar to 15 Ma; and finally at similar to 4 Ma, the present plate edge was formed, Alcock and Sewell Rises were separated by formation of the Central Andaman Basin, and the faulting moved onshore from the Mentawai Fault to the Sumatra Fault System bisecting Sumatra. (c) 2005 Elsevier Ltd. All rights reserved.

Alam, M, Alam MM, Curray JR, Chowdhury ALR, Gani MR.  2003.  An overview of the sedimentary geology of the Bengal Basin in relation to the regional tectonic framework and basin-fill history. Sedimentary Geology. 155:179-208.   10.1016/s0037-0738(02)00180-x   AbstractWebsite

The Bengal Basin in the northeastern part of Indian subcontinent, between the Indian Shield and Indo-Burman Ranges, comprises three geo-tectonic provinces: (1) The Stable Shelf; (2) The Central Deep Basin (extending from the Sylhet Trough in the northeast towards the Hatia Trough in the south); and (3) The Chittagong-Tripura Fold Belt. Due to location of the basin at the juncture of three interacting plates, viz., the Indian, Burma and Tibetan (Eurasian) Plates, the basin-fill history of these geotectonic provinces varied considerably. Precambrian metasediments and Permian-Carboniferous rocks have been encountered only in drill holes in the stable shelf province. After Precambrian peneplanation of the Indian Shield, sedimentation in the Bengal Basin started in isolated graben-controlled basins on the basement. With the breakup of Gondwanaland in the Jurassic and Cretaceous, and northward movement of the Indian Plate, the basin started downwarping in the Early Cretaceous and sedimentation started on the stable shelf and deep basin; and since then sedimentation has been continuous for most of the basin. Subsidence of the basin can be attributed to differential adjustments of the crust, collision with the various elements of south Asia, and uplift of the eastern Himalayas and the Indo-Burman Ranges. Movements along several well-established faults were initiated following the breakup of Gondwanaland and during downwarping in the Cretaceous. By Eocene, because of a major marine transgression, the stable shelf came under a carbonate regime, whereas the deep basinal area was dominated by deep-water sedimentation. A major switch in sedimentation pattern over the Bengal Basin occurred during the Middle Eocene to Early Miocene as a result of collision of India with the Burma and Tibetan Blocks. The influx of elastic sediment into the basin from the Himalayas to the north and the Indo-Burman Ranges to the east rapidly increased at this time; and this was followed by an increase in the rate of subsidence of the basin. At this stage, deep marine sedimentation dominated in the deep basinal part, while deep to shallow marine conditions prevailed in the eastern part of the basin. By Middle Miocene, with continuing collision events between the plates and uplift in the Himalayas and Indo-Burman Ranges, a huge influx of elastic sediments came into the basin from the northeast and east. Throughout the Miocene, the depositional settings continued to vary from deep marine in the basin to shallow and coastal marine in the marginal parts of the basin. From Pliocene onwards, large amounts of sediment were filling the Bengal Basin from the west and northwest; and major delta building processes continued to develop the present-day delta morphology. Since the Cretaceous, architecture of them Bengal Basin has been changing due to the collision pattern and movements of the major plates in the region. However, three notable changes in basin configuration can be recognized that occurred during Early Eocene, Middle Miocene and Plio-Pleistocene times, when both the paleogeographic settings and source areas changed. The present basin configuration with the Ganges - Brahmaputra delta system on the north and the Bengal Deep Sea Fan on the south was established during the later part of Pliocene and Pleistocene; and delta progradation since then has been strongly affected by orogeny in the eastern Himalayas. Pleistocene glacial activities in the north accompanied sea level changes in the Bay of Bengal. (C) 2002 Elsevier Science B.V All rights reserved.

Curray, JR, Emmel FJ, Moore DG.  2002.  The Bengal Fan: morphology, geometry, stratigraphy, history and processes. Marine and Petroleum Geology. 19:1191-1223.   10.1016/s0264-8172(03)00035-7   AbstractWebsite

The Bengal Fan is the largest submarine fan in the world, with a length of about 3000 km, a width of about 1000 km and a maximum thickness of 16.5 km. It has been formed as a direct result of the India-Asia collision and uplift of the Himalayas and the Tibetan Plateau. It is currently supplied mainly by the confluent Ganges and Brahmaputra Rivers, with smaller contributions of sediment from several other large rivers in Bangladesh and India. The sedimentary section of the fan is subdivided by seismic stratigraphy by two unconformities which have been tentatively dated as upper Miocene and lower Eocene by long correlations from DSDP Leg 22 and ODP Legs 116 and 121. The upper Miocene unconformity is the time of onset of the diffuse plate edge or intraplate deformation in the southern or lower fan. The lower Eocene unconformity, a hiatus which increases in duration down the fan, is postulated to be the time of first deposition of the fan, starting at the base of the Bangladesh slope shortly after the initial India-Asia collision. The Quaternary of the upper fan comprises a section of enormous channel-levee complexes which were built on top of the preexisting fan surface during lowered sea level by very large turbidity currents. The Quaternary section of the upper fan can be subdivided by seismic stratigraphy into four subfans, which show lateral shifting as a function of the location of the submarine canyon supplying the turbidity currents and sediments. There was probably more than one active canyon at times during the Quaternary, but each one had only one active fan valley system and subfan at any given time. The fan currently has one submarine canyon source and one active fan valley system which extends the length of the active subfan. Since the Holocene rise in sea level, however, the head of the submarine canyon lies in a mid-shelf location, and the supply of sediment to the canyon and fan valley is greatly reduced from the huge supply which had existed during Pleistocene lowered sea level. Holocene turbidity currents are small and infrequent, and the active channel is partially filled in about the middle of the fan by deposition from these small turbidity currents. Channel migration within the fan valley system occurs by avulsion only in the upper fan and in the upper middle fan in the area of highest rates of deposition. Abandoned fan valleys are filled rapidly in the upper fan, but many open abandoned fan valleys are found on the lower fan. A sequence of time of activity of the important open channels is proposed, culminating with formation of the one currently active channel at about 12,000 years BP. (C) 2003 Elsevier Science Ltd. All rights reserved.

Curray, JR.  1996.  Origin of beach ridges: Comment. Marine Geology. 136:121-125.   10.1016/s0025-3227(96)00040-0   AbstractWebsite

Tanner (1995) has proposed that most common strand plain sandy beach ridges (his swash-built type) have been formed by a sea level rise-and-fall couplet of 5-30 cm, with a periodicity which is most commonly 30-60 years, but which ranges from as little as 3 to as much as 60 years. While such a mechanism could perhaps apply to beach ridges in lakes, if sea level has fluctuated with such regularity for the past several thousand years, all open ocean beach ridge periodicities should be the same, and furthermore this sea level signal would surely have been detected by physical oceanographers. Curray et al. (1969) described a strand plain of several hundred beach ridges on the western Mexican coast with cyclic formation of ridges varying from 12.2 to 16.5 years. The mechanism of formation invoked was periodic building of offshore bars to above sea level after sufficient sand had been transported into the area and during an optimal combination of oceanographic conditions.

Curray, JR.  1994.  Sediment Volume and Mass beneath the Bay of Bengal. Earth and Planetary Science Letters. 125:371-383.   10.1016/0012-821x(94)90227-5   AbstractWebsite

Rates of sediment accumulation and the amount of sedimentary fill in depocenters lying downstream of erosion in the Himalayas and Tibet can provide some insight into tectonics and geological history. The objective of this paper is to put on record the best estimates which are possible with existing data of the volume and mass of sediments, sedimentary rock and metasedimentary rock beneath the sea floor of the Bay of Bengal. The sedimentary section in the Bay of Bengal is divided into two parts: (1) Eocene through Holocene, sediments and sedimentary rocks which post-date the initial India-Asia collision: volume - 12.5 X 10(6) km3; mass = 2.88 X 10(16) t; this is most of the Bengal Fan, including its eastern lobe, the Nicobar Fan, plus some of the outer Bengal Delta; (2) Early Cretaceous through Paleocene, pre-collision sedimentary and metasedimentary rocks: volume = 4.36 X 10(6) km 3; mass = 1.13 to 1.18 X 10(16) t; these are interpreted as continental rise and pelagic deposits.

Paull, CK, Twichell DC, Spiess FN, Curray JR.  1991.  Morphological Development of the Florida Escarpment - Observations on the Generation of Time Transgressive Unconformities in Carbonate Terrains. Marine Geology. 101:181-201.   10.1016/0025-3227(91)90070-k   AbstractWebsite

An unconformity of 100 m.yr magnitude continues to form on the western edge of the Florida-Bahama Platform, near 26-degrees-N, where distal Mississippi Fan sediments are progressively burying the Florida Escarpment. Multiple perspectives of the developing unconformity's morphology are revealed using available technologies including GLORIA images of the entire platform's edge, Seabeam bathymetric contours, and Deep-Tow's high resolution side-scan data calibrated with bottom photographs. The structure and stratigraphy of the buried escarpment and the associated unconformity are resolved by airgun, sparker, and Deep-Tow's 4 kHz seismic reflection data; we summarize the morphological data on the exposed part of the unconformity and the sedimentary deposits accumulating in the basin above the unconformity. The exposed cliff face is composed of a staircase of bedding-plane terraces which are developed along joint planes. The terraces extend 100-1000 m along the escarpment's face, and the intervening vertical walls are up to 100 m high. The jointed morphology of this Mesozoic limestone cliff apparently reflects erosional exposure of its interior anatomy rather than its accretionary shape. The change in slope between the platform face and the abyssal plain is very abrupt. In places along the contact between the escarpment and fan sediments, reduced chemical-charged brine seeps occur, which locally cause carbonate dissolution and precipitation, sulfide mineralization, and the deposition of a fossiliferous and organic carbon-rich lens associated with chemosynthetic communities. These seep deposits and escarpment-derived megabreccias intercalate with basinal sediments that overlie the unconformity. Because surface seismic reflection data do not produce images of the escarpment's face that closely reflect the exposed escarpment's morphology, they must also be of limited value in characterizing the surface of similar steeply dipping buried escarpments. Thus, the downslope extent of the heavily eroded platform edge is unclear.

Curray, JR.  1991.  Possible Greenschist Metamorphism at the Base of a 22-Km Sedimentary Section, Bay of Bengal. Geology. 19:1097-1100.   10.1130/0091-7613(1991)019<1097:pgmatb>;2   AbstractWebsite

Reinterpretation of seismic refraction and reflection data in the Bay of Bengal suggests a maximum thickness of sedimentary deposits of more than 22 km beneath the Bangladesh continental shelf. Revised correlation of an early Eocene unconformity-which is interpreted as representing the time of the India-Asia collision-subdivides these deposits into (1) a Cretaceous and Paleocene continental-rise section up to 6 km thick off the Indian margin and (2) 16 km of overlying Bengal Fan sediments and sedimentary rocks derived mainly from erosion of the region uplifted following the collision. Pressure and temperature conditions within the deeply buried continental rise are in the field of greenschist facies metamorphism. The resulting metasedimentary rocks would have velocities and densities compatible with the refraction data and isostatic calculations.

Curray, JR, Munasinghe T.  1991.  Origin of the Rajmahal Traps and the 85-Degrees-E Ridge - Preliminary Reconstructions of the Trace of the Crozet Hotspot. Geology. 19:1237-1240.   10.1130/0091-7613(1991)019<1237:ootrta>;2   AbstractWebsite

The 85-degrees-E Ridge is a buried aseismic ridge approximately parallel to and west of the Ninetyeast Ridge in the northeastern Indian Ocean. It was previously shown to be of probable volcanic origin emplaced on very young oceanic crust, but no satisfactory model of emplacement of the rocks was offered. We propose a model of origin of the Rajmahal Traps of northeastern India, the 85-degrees-E Ridge, and Afanasy Nikitin Seamount as the trace of the hotspot that now lies beneath the Crozet Islands in the southern Indian Ocean. This reconstruction places the Kerguelen hotspot, which formed the Ninetyeast Ridge, at the triple junction between Greater India, Australia, and Antartica before the breakup of eastern Gondwana.

Paull, CK, Commeau RF, Curray JR, Neumann AC.  1991.  Seabed Measurements of Modern Corrosion Rates on the Florida Escarpment. Geo-Marine Letters. 11:16-22.   10.1007/bf02431050   AbstractWebsite

A mooring containing diverse carbonate and anhydrite substrates was exposed to bottom waters for 9 months at the base of the Florida Escarpment to determine the influence of dissolution on the development of this continental margin. Weight loss was measured on all samples. Etching, pitting, and loss of the original framework components were observed on substrates with known characteristics. Extrapolations of modern dissolution rates predict only about 1.6 meters of corrosion per million years. However, more rapid anhydrite dissolution, up to 1 km per million years, would cause exposed anhydrite beds to undercut and destabilize intercalated limestones.

Paull, CK, Spiess FN, Curray JR, Twichell DC.  1990.  Origin of Florida Canyon and the Role of Spring Sapping on the Formation of Submarine Box Canyons. Geological Society of America Bulletin. 102:502-515.   10.1130/0016-7606(1990)102<0502:oofcat>;2   Website
Curray, JR.  1989.  The Sunda Arc - a Model for Oblique Plate Convergence. Netherlands Journal of Sea Research. 24:131-140.   10.1016/0077-7579(89)90144-0   Website
Curray, JR, Munasinghe T.  1989.  Timing of Intraplate Deformation, Northeastern Indian-Ocean. Earth and Planetary Science Letters. 94:71-77.   10.1016/0012-821x(89)90084-8   Website
Paull, CK, Spiess EN, Curray JR, Twitchell D.  1988.  Morphology of Florida Escarpment Chemosynthetic Brine Seep Community Sites - Deep-Tow, Seabeam, and Gloria Surveys. Aapg Bulletin-American Association of Petroleum Geologists. 72:233-233.
Curray, JR.  1987.  Variations around Sunda Arc. Aapg Bulletin-American Association of Petroleum Geologists. 71:545-545.Website
Emery, KO, Dietz RS, Kuhn GG, Curray JR.  1986.  Shepard,Francis,Parker (1897-1985). Aapg Bulletin-American Association of Petroleum Geologists. 70:331-333.Website
Paull, CK, Hecker B, Commeau R, Freemanlynde RP, Neumann C, Corso WP, Golubic S, Hook JE, Sikes E, Curray J.  1984.  Biological Communities at the Florida Escarpment Resemble Hydrothermal Vent Taxa. Science. 226:965-967.   10.1126/science.226.4677.965   Website
Liu, CS, Curray JR, McDonald JM.  1983.  New Constraints on the Tectonic Evolution of the Eastern Indian-Ocean. Earth and Planetary Science Letters. 65:331-342.   10.1016/0012-821x(83)90171-1   Website
Moore, DG, Curray JR.  1982.  Geologic and Tectonic History of the Gulf of California. Initial Reports of the Deep Sea Drilling Project. 64:1279-1294.Website
Kelts, K, Curray JR, Moore DG.  1982.  Introduction and Explanatory Notes. Initial Reports of the Deep Sea Drilling Project. 64:5-26.Website
Curray, JR, Moore DG.  1982.  Introduction to the Baja California Passive-Margin-Transect Symposium. Initial Reports of the Deep Sea Drilling Project. 64:1067-1069.Website