Uchupi Elazar

No Thumbnail Available
Last Name
Uchupi
First Name
Elazar
ORCID

Filters

11
Reset filters

Settings

Search Results

Now showing 1 - 11 of 11
  • Technical Report
    Seismic reflection, magnetic, and gravity profiles of the eastern Atlantic continental margin and adjacent deep-sea floor. II. Congo Canyon (Republic of Zaire) to Lisbon (Portugal)
    (Woods Hole Oceanographic Institution, 1974-04) Uchupi, Elazar ; Emery, Kenneth O.
    One of the programs of the International Decade of Ocean Exploration (I.D.O.E.) is a geological and geophysical study of the eastern Atlantic continental margin and adjacent deep-sea floor. This report is a compilation of the geophysical traverses made from the Congo Canyon (Republic of Zaire) to Lisbon, Portugal during the first half of 1973. Also included in the atlas are geophysical traverses from Woods Hole to Dakar and from Dakar to Latitude 10°N made during January-February, 1972.
  • Preprint
    Geomorphology and shallow structure of a segment of the Atlantic Patagonian margin
    ( 2013-03) Munoz, Araceli ; Acosta, Juan ; Cristobo, J. ; Druet, M. ; Uchupi, Elazar ; Atlantis Group 1
    We study an area little known of the Atlantic Patagonian margin from 44˚30’S to 47˚40’S and from 59˚W to nearly 61˚W. The multi-beam bathymetry coupled with high resolution seismic reflection profiles, have provided details on the morphology and shallow acoustic structure on this area. The main morphological characteristics of the seafloor features on the shelf and middle slope are described. The Atlantic Patagonian continental shelf north of 45˚40’S is located at a depth of 170-200 m depths, south of this latitude the shelf edge is at 128 to 200 m. The shelf surface is marred by circular depression and ridges oriented oblique to the shelf edge. The upper slope and upper middle slope are plowing by icebergs from Antarctica in Pleistocene and local reefs of cold-water coral further enhance the topography of the area. In the middle slope there are two terraces, the 20 to 60 km wide Nágera and the 15 to 60 km wide Perito Moreno terraces, showing moats, hollows, pot holes, sediment drifts and sediment waves. The terraces may have been formed in Late Miocene whereas the other forms are of Pleistocene age. Other features are a sediment swell south of 47˚S and seven submarine canyons on the middle slope. These incipient canyons have been developed in the middle slope by retrogressive erosion, some terminating on the upper middle slope, and others on the upper slope and the canyon 6 breaching the shelf edge. Individual seafloor features existing on the Atlantic Patagonian Margin have been classified into two main groups according to their origin: along and across-slope processes. These primary agents were supplemented by endogenic processes such as expulsion of gas/water, diapirism of high-pressure mud and folding/faulting. The results suggest that today down-slope processes on the slope are practically non-existent and that the morphology of the upper and middle slope is slowly being remoulded by along-slope bottom currents.
  • Working Paper
    R/V Knorr Voyage 134-15 Uchupi video docs
    (Woods Hole Oceanographic Institution, 1988-08) Ballard, Robert D. ; Uchupi, Elazar
    Data Workup From AMPHORA Site This is a list of the work to be done on the data from the AMPHORA Site. All these data are from STARELLA Leg DSL88-02. No data from Starella Leg 1 or the Knorr cruise are included in this list.
  • Technical Report
    Seismic reflection, magnetic, and gravity profiles of the eastern Atlantic continental margin and adjacent deep-sea floor. I. Cape Francis (South Africa) to Congo Canyon (Republic of Zaire)
    (Woods Hole Oceanographic Institution, 1972-12) Uchupi, Elazar ; Emery, Kenneth O.
    One of the programs of the International Decade of Ocean Exploration (!DOE) is a four-year geophysical and geological study of the Eastern Atlantic Continental Margin and the adjacent deep·sea floor. It was designed to learn more of the date and manner by which Africa became separated from South America and the subsequent history and development of the African continental margin and adjoining deep-sea floor. The traverses also serve to outline large sedimentary basins that may be potential reservoirs of petroleum. Subsequent more detailed exploration and eventual exploitation of these basins may be conducted or controlled by the adjacent African nations under whose jurisdiction the areas belong. This report is a compilation of the geophysical traverses made from Cape Francis (South Africa) to the Congo Canyon (Republic of Zaire) during the first half of 1972.
  • Working Paper
    Late Cenozoic geology of the Central Persian (Arabian) Gulf from industry well data and seismic profiles
    (Woods Hole Oceanographic Institution, 1988-04) Swift, Stephen A. ; Uchupi, Elazar ; Ross, David A.
    Industry seismic reflection profiles shot in the 60's and early 70's in the central Persian (Arabian) Gulf are used to map two late Tertiary unconformities, and velocity data from a centrally located well is used to convert travel time to depth to the unconformities. The deeper horizon correlates with a regional unconformity at the end of the Eocene in most wells and dips monotonically to the northeast, whereas the shallower horizon is flatter and correlates with the mid-upper Miocene section in one well. Isopach maps based on wells indicate that sedimentation was relatively uniform across the region until the middle to late Miocene. Sediments deposited since the late Miocene thicken from 100-200 m on the Arabian side of the Gulf to >1000 m near Iran reflecting deposition of sediments eroded from the rapidly uplifting Zagros fold-belt. As a result of the rapid deposition, the velocity gradient in the upper 1 km decreases from ~4 km/sec per km near Arabia to about 2 km/sec per km on the Iranian side of the Gulf.
  • Preprint
    Geomorphology and Neogene tectonic evolution of the Palomares continental margin (Western Mediterranean)
    ( 2016-03) Gomez de la Peña, Laura ; Gracia, Eulalia ; Munoz, Araceli ; Acosta, Juan ; Gomez-Ballesteros, María ; Ranero, Cesar R. ; Uchupi, Elazar
    The Palomares continental margin is located in the southeastern part of Spain. The margin main structure was formed during Miocene times, and it is currently part of the wide deformation zone characterizing the region between the Iberian and African plates, where no well-defined plate boundary occurs. The convergence between these two plates is here accommodated by several structures, including the left lateral strike-slip Palomares Fault. The region is characterized by sparse, low to moderate magnitude (Mw < 5.2) shallow instrumental earthquakes, although large historical events have also occurred. To understand the recent tectonic history of the margin we analyze new high-resolution multibeam bathymetry data and re-processed three multichannel seismic reflection profiles crossing the main structures. The analysis of seafloor morphology and associated subsurface structure provides new insights of the active tectonic features of the area. In contrast to other segments of the southeastern Iberian margin, the Palomares margin contains numerous large and comparatively closely spaced canyons with heads that reach near the coast. The margin relief is also characterized by the presence of three prominent igneous submarine ridges that include the Aguilas, Abubacer and Maimonides highs. Erosive processes evidenced by a number of scars, slope failures, gullies and canyon incisions shape the present-day relief of the Palomares margin. Seismic images reveal the deep structure distinguishing between Miocene structures related to the formation of the margin and currently active features, some of which may reactivate inherited structures. The structure of the margin started with an extensional phase accompanied by volcanic accretion during the Serravallian, followed by a compressional pulse that started during the Latemost Tortonian. Nowadays, tectonic activity offshore is subdued and limited to few, minor faults, in comparison with the activity recorded onshore. The deep Algero-Balearic Basin is affected by surficial processes, associated to halokinesis of Messinian evaporites.
  • Working Paper
    R/V Knorr Voyage 134-15 Jason ROV 89 Long Baseline Acoustic Navigation, SHARPS navigation
    (Woods Hole Oceanographic Institution, 1988-08) Gegg, Stephen ; Uchupi, Elazar
    A collection of documentation, memos, notes and log files relating to Long Baseline Acoustic Navigation, SHARPS navigation, vehicle control and JASON ROV general information.
  • Preprint
    The morpho-tectonic setting of the Southeast margin of Iberia and the adjacent oceanic Algero-Balearic Basin
    ( 2013-04) Acosta, Juan ; Fontan, A. ; Munoz, Araceli ; Munoz-Martin, A. ; Rivera, J. ; Uchupi, Elazar
    Multi-beam bathymetry and high-resolution low-penetration seismic reflection profiles of the offshore extensions of the Bétic Internal Zone off Sierra de Cartagena-La Unión margin along its south side and the Mar Menor margin along its east side, the Mazarrón Escarpment forming its southern boundary and the adjacent oceanic Algero-Balearic basin have provided images of the neo-tectonic structures of the region equal to those provided by subaerial photography. For the first time we mapped with unprecedented detail the Mazarrón Escarpment and the Southeast margin of Iberia. The first-order structures of the region are due to the consequence of the collision of the African and Eurasian plates during the Alpine orogeny in late Oligocene-Middle Miocene, the westward migration of the Alborán plate in the Middle Miocene and the desiccation of the Mediterranean in the Messinian (Late Miocene) that led to the deposition of evaporites in the Algero-Balearic basin and erosion of the Mazarrón Escarpment, the Sierra de Cartagena-La Unión shelf, the Mar Menor margin and the adjacent coast. Our data images second order tectonic features (neo-tectonic features) superimposed on the larger structures. These include the deformation of the strata in the Algero-Balearic basin by the gliding of the Plio-Quaternary sediments on Messinian halite on the margins of the basin and sediment loading in its center, the Late Miocene-Quaternary deformation of the area north of the Mazarrón Escarpment resulting from the continuous oblique convergence of the African and Eurasian plates in a NNW-SSE direction, the Miocene to Pleistocene volcanic edifices and pinnacles (dikes), the pockmarks formed by the extrusion of gas/water via faults and the massive gravitational failure of the Mazarrón Escarpment triggered by this plate convergence. The data also show in detail features formed on the Mazarrón Escarpment during the Messinian, Pliocene and Pleistocene regressions and those on the shelf formed during the Pleistocene glacially induced regressions/transgression and sediment drifts generated by modern currents.
  • Preprint
    Sediment drifts and cold-water coral reefs in the Patagonian upper and middle continental slope
    ( 2012-05) Munoz, Araceli ; Cristobo, J. ; Rios, P. ; Druet, M. ; Polonio, V. ; Uchupi, Elazar ; Acosta, Juan ; Iglesias, S. ; Portela, J. ; del Rio, J. L. ; Parra, S. ; Sacau, M. ; Vilela, R. ; Patrocinio, T. ; Almon, B. ; Elvira, E. ; Jimenez, P. ; Fontan, A. ; Alcala, C. ; Lopez, V.
    The north flowing Falkland / Malvinas Current has generated sediment drifts at a depth of 1200-1600 m in the Patagonian middle continental slope out of early Holocene hemipelagics, late Pleistocene ice rafted clastics, and Neogene fluvial sediments. Possibly there may be two generations of drifts, Pleistocene on the outer middle slope and Holocene on the inner shelf. The ice rafted debris originated in Antarctica, at a distance of 2000 to 4000 km south of Patagonia. Scattered over the upper and middle slopes, at depths ranging from 300 to 1400 m, are cold-water coral reefs of less than a meter to about ten of meters in relief. It is inferred that most of cold-water coral structures flourish as a consequence of the Falkland /Malvinas Current that concentrates the food supply at the reef sites. Growth of cold-water coral reefs, documented by digital submarine photographs on the upper slope, at a depth of 300/400 m, may be promoted by upwelling of nutrient-rich waters and associated plankton blooms created by the intrusion of Falkland /Malvinas Current onto the outer shelf.
  • Working Paper
    R/V Knorr Voyage 134-15 STARELLA Leg DSLBB-02
    (Woods Hole Oceanographic Institution, 1988-08) Uchupi, Elazar
    This is a list of the work to be done on the data from the AMPHORA site. All these data are from STARELLA Leg DSLBB-02. No data from Starella Leg 1 or the Knorr cruise are included in this list.
  • Article
    A catastrophic meltwater flood event and the formation of the Hudson Shelf Valley
    (Elsevier B.V., 2007-01-04) Thieler, E. Robert ; Butman, Bradford ; Schwab, William C. ; Allison, Mead A. ; Driscoll, Neal W. ; Donnelly, Jeffrey P. ; Uchupi, Elazar
    The Hudson Shelf Valley (HSV) is the largest physiographic feature on the U.S. mid-Atlantic continental shelf. The 150-km long valley is the submerged extension of the ancestral Hudson River Valley that connects to the Hudson Canyon. Unlike other incised valleys on the mid-Atlantic shelf, it has not been infilled with sediment during the Holocene. Analyses of multibeam bathymetry, acoustic backscatter intensity, and high-resolution seismic reflection profiles reveal morphologic and stratigraphic evidence for a catastrophic meltwater flood event that formed the modern HSV. The valley and its distal deposits record a discrete flood event that carved 15-m high banks, formed a 120-km2 field of 3- to 6-m high bedforms, and deposited a subaqueous delta on the outer shelf. The HSV is inferred to have been carved initially by precipitation and meltwater runoff during the advance of the Laurentide Ice Sheet, and later by the drainage of early proglacial lakes through stable spillways. A flood resulting from the failure of the terminal moraine dam at the Narrows between Staten Island and Long Island, New York, allowed glacial lakes in the Hudson and Ontario basins to drain across the continental shelf. Water level changes in the Hudson River basin associated with the catastrophic drainage of glacial lakes Iroquois, Vermont, and Albany around 11,450 14C year BP (~ 13,350 cal BP) may have precipitated dam failure at the Narrows. This 3200 km3 discharge of freshwater entered the North Atlantic proximal to the Gulf Stream and may have affected thermohaline circulation at the onset of the Intra-Allerød Cold Period. Based on bedform characteristics and fluvial morphology in the HSV, the maximum freshwater flux during the flood event is estimated to be ~ 0.46 Sv for a duration of ~ 80 days.