Download or read book The Influence of Bottom Currents on the Sedimentary Evolution of the Alboran Sea During the Pliocene and Quaternary written by Carmen Juan Valenzuela and published by . This book was released on 2016 with total page 351 pages. Available in PDF, EPUB and Kindle. Book excerpt: "An interdisciplinary study of the geomorphology, sedimentology, stratigraphy and physical oceanography of the deep-sea environments of the Alboran Sea (south-western Mediterranean Sea) has been carried out with the purpose of evidencing and understanding the role of bottom currents in the sedimentary evolution of the Spanish and Moroccan continental margins and adjacent basins during the Pliocene and Quaternary. This study was conducted using swath bathymetry data, more than 1900 profiles consisting of parametric, single- and multi-channel seismic records, scientific and commercial wells, sediment cores, and hydrographic data comprising: Conductivity, Temperature and Depth (CTD) profiles, Acoustic Doppler Current (ADCP) profiles, and EK60 echograms. Here, for the first time, a morphosedimentary scenario with a wide spectrum of depositional (plastered, sheeted, channel-related, mounded confined, elongated and separated drifts) and erosional (terraces, escarpments, moats, channels and furrows) contourite features are described in the Alboran Sea, from the shelf break to the basin floor. Hydrographic data offers new insights into the distribution of the Mediterranean water masses, and reveals that the bottom circulation of the Western Intermediate Water (WIW) and the Levantine Intermediate Water (LIW) interact with the Spanish slope, and the Western Mediterranean Deep Water (WMDW) with the Moroccan slope, Spanish base- of-slope and deep basins. The integration of distinct datasets and approaches allow a new sedimentary model to be proposed for the Alboran Sea that underlines the significance of bottom current processes in shaping deep-sea morphology. This model suggests that the bottom circulation of water masses governs physiography that the interface positions of water-masses with contrasting densities sculpt terraces at a regional scale, and that morphological obstacles play an essential role in the local control of processes and water- mass distribution. An analysis of the seismic stratigraphy from the Pliocene and Quaternary sequences has enabled to update and rename the stratigraphic boundaries and establish a new seismic stratigraphy for the Alboran Sea, after relocating the base of the Quaternary from 1.8 to 2.6Ma. Additionally, the seismic analysis involves the presentation and discussion for the first time of the evidence for contourite features reaching the scale of the Alboran Basin. Contourite drifts (plastered, sheeted, elongated separated and confined mounded drifts) and erosive features (terraces, escarpments, moats, channels, furrows) were developed under the continuous influence of Mediterranean water masses after the opening of the Strait of Gibraltar ( -5.33Ma). At least two primary factors have controlled the contourite features in this sea: i) tectonics, which has governed the relocation of the main Mediterranean flow pathways and their circulation patterns; and ii) climate, which has influenced both water-mass conditions (depth and density contrast of the interfaces) and hinterland sediment sources, conditioning the morphoseismic expression and growth pattern of drifts and terrace formation (dimensions). The distribution of contourite features through time and space allows to propose three main scenarios for ocean circulation since the opening of the Strait of Gibraltar: i) Atlantic Zanclean flooding; ii) the Pliocene sea, with two different stages for the dense circulation and characterised by poorly-defined and unstable interfaces for the Atlantic Waters (AW), light and dense Mediterranean waters and the presence of a strong countercurrent in the Western Basin; and iii) the Quaternary sea, characterised by tabular Mediterranean water masses with multiple current dynamics, increasingly important density contrasts, and climate shifts causing major vertical and horizontal displacement of the interfaces. These stages reflect variability in the bottom current regimes and related alongslope efficiency in terms of transport, deposition and erosion. The detailed seismic analysis of the units making up the Pliocene and Quaternary sequences allows for the first time, to make an in-depth analysis of the contourite features, turbidite systems and mass-movement deposits, and map them through time. These maps are enormously helpful when it comes to understanding the sedimentary architecture of the Spanish and Moroccan continental margins and basins, as well as for decoding the palaeoceanographic processes from a geological perspective. Two main contourite depositional systems are defined: the Intermediate Mediterranean Contourite System (IMCS), formed under the action of the Light Mediterranean Waters (LMW) on the Spanish margin, and the Deep Mediterranean Contourite System (DMCS), formed under the action of the Dense Mediterranean Waters (DMW) mainly on the Moroccan margin and basins. The characterisation of the terraces as contourite features that form under the combination of two water masses, has also led to the definition of the Atlantic Contourite System (ACS). The occurrence of several contourite depositional systems has led to the suggestion of a new term, not heretofore considered in the literature: Multiple Contourite Depositional System (MCDS), which refers to the set of different CDSs that occurs in the same area and evolving under the action of multiple water masses. In addition, twenty turbidite systems have been characterised, revealing that they are responsible for the different sedimentary architecture of the Spanish margin, where they coexist with contourites, as on the Moroccan margin the turbidite systems are less well developed. The mass-movement deposits are mainly related to the reworking of the contourites draping the highs. Mainly contourites but also turbidites, allowed to define from a geological perspective the basic oceanographic processes and to determine their occurrence, relative magnitude and energy, and time of action. This PhD thesis also explains the uneven development of the turbidite systems in the Alboran Sea, which is interpreted to be conditioned by the interaction of alongslope with downslope processes. Several morphological and sedimentary signatures produced by the interaction between both processes have been identified in the Pliocene and Quaternary records, as well as on the present-day seafloor of the Alboran Sea. The interaction scenarios move between two-end-members: from bottom currents dominating gravity flows to gravity flows dominating contour currents. In between these extreme cases, the alternation and mutual influence of both processes can occur. Two different conceptual models of interaction are proposed for the Spanish and Moroccan margins. i) On the Spanish margin, the alongslope and downslope interaction is especially complex and varied, with both regional and local effects on the turbidite systems. This is because here the turbidite systems are influenced at different water depths by Atlantic and Mediterranean water masses and their interfaces, with current flows that change across- and downslope. ii) On the Moroccan margin, the vigorous action of the WMDW primarily inhibits the formation of canyons and associated deposits. The findings of this PhD thesis suggest that the relevance of bottom-water processes in deep sea must be reevaluated. It is concluded that understanding the influence of bottom currents is not only essential for reconstructing present and past water mass circulation, but also for recognising sea floor morphologies and decoding the sedimentary stacking pattern and evolution of deposits, as well as global climate and periods of eustatic variation."--TDX.

Download or read book Influence of Abyssal Circulation on Sedimentary Accumulations in Space and Time written by and published by Elsevier. This book was released on 2011-09-22 with total page 225 pages. Available in PDF, EPUB and Kindle. Book excerpt: Influence of Abyssal Circulation on Sedimentary Accumulations in Space and Time

Download or read book The Geology of Iberia A Geodynamic Approach written by Cecilio Quesada and published by Springer. This book was released on 2019-05-28 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pursuing an innovative, global approach, this unique book provides an updated review of the geology of Iberia and its continental margins from a geodynamic perspective. Owing to its location close to successive plate margins, Iberia has played a pivotal role in the geodynamic evolution of the Gondwanan, Rheic, Pangea, Tethys and Eurasian plates over the last 600 Ma of Earth’s history. The geological record starts with the amalgamation of Gondwana in the Neoproterozoic, which was succeeded by the rifting and spreading of the Rheic ocean; its demise, which led to the amalgamation of Pangea in the late Paleozoic; the rifting and spreading of several arms of the Neotethys ocean in the Mesozoic Era and their ongoing closure, which was responsible for the Alpine orogeny. The significant advances in the last 20 years have increasingly attracted international interest in exploring the geology of the Iberian Peninsula. This volume focuses on the Cenozoic basins of the Iberian Geology and consequently the most recent sedimentary features in the Iberian Geology apart of the active ones. In this book, you will find a detailed explanation of the alpine foreland basins, the extension of the west Mediterranean as well as the latest magmatism in Iberia.

Download or read book Alboran Sea Ecosystems and Marine Resources written by José Carlos Báez and published by Springer Nature. This book was released on 2021-05-22 with total page 942 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Alboran Sea represents a regional Mediterranean space where North and South worlds merges, creating a geopolitical region where marine resources and maritime activities should be managed from a national and international perspectives. It is widely known, that currently the planet is suffering a global change, and it is also affecting the Alboran Sea, its ecosystems and populations. An important first step to update a paramount vision on this region is to understand the climatic, geologic and oceanographic, including biochemical cycles, process which shapes the rich geodiversity, biodiversity, the productivity, and the sustainable use of the marine resources from Alboran Sea. The fisheries management system should take into account marine environmental variability to achieve biological sustainability of marine resources. Well-funded policy-makers’ decisions require a sound science based knowledge of the interaction between the marine environment and commercial stocks. This is because the role of marine environment in the evolution of fish stocks is sometimes even more important than the one played by fishers in the commercial exploitation of them. Finally, we should analyze the different aspects of political context that could affect the management of the resources from Alboran Sea in the context of climate change. This book reviews different aspects of the Alboran Sea to help understand the current situation from the original Tethis Ocean. The book is divided into four blocks: (i) Oceanographic, geological and ecological context (chapters 2 to 7), (ii) biodiversity and ecosystems distribution (chapters 8 to 12), (iii) fisheries resources and aquaculture (chapters 13 to 20), and (iv) conservation, management and marine polices (chapters 21 to 25).

Download or read book Sediment Waves and Other Evidence of Paleo bottom Currents at Two Locations in the Deep Arctic Ocean written by and published by . This book was released on 1979 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Sediment Flux to Basins written by Stuart J. Jones and published by Geological Society of London. This book was released on 2002 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Paleocurrents and Basin Analysis written by P. E. Potter and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 473 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of paleocurrents, since 1963, is now a very routine part of sedimentology, and more and more such studies are finding use in other fields. Thus it seemed appropriate for us to review post-1963 developments and present them in a compact manner for the interested reader. Instead of rewriting a second edition, which thirteen years later we would organize in a completely dif ferent way, we have brought each chapter up to date with new material up to 1976. A new update supplement has in this edition been inserted after each one of the original chapters. We have stayed close to the original theme of paleocurrents-how to measure them and how to use them to solve geological problems ranging in scale from the hand specimen to the sedimentary basin and beyond. We have used many annotated references and tables to help pre sent this information to the reader. The reader will note that we have cited a few 1962 references - pUblications that appeared too late to be cited in the original 1963 edition. A few times we have also cited a reference which was included in the first edition. These are marked with an asterisk and hence do not appear in the new lists of references. We have been aided by many. In Cincinnati, WANDA OSBORNE and JEAN CARROL did typing and RICHARD SPOHN, the University's geological librarian, was very helpful in obtaining many references to the literature.

Download or read book Geologic Effects of Ocean Bottom Currents written by Charles D. Hollister and published by . This book was released on 1972 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Quaternary Sea Level Changes written by Colin V. Murray-Wallace and published by Cambridge University Press. This book was released on 2014-01-30 with total page 503 pages. Available in PDF, EPUB and Kindle. Book excerpt: There have been significant changes in sea level over the past two million years, and a complete understanding of natural cycles of change as well as anthropogenic effects is imperative for future global development. This book reviews the history of research into these sea-level changes and summarises the methods and analytical approaches used to interpret evidence for sea-level changes. It provides an overview of changing climates during the Quaternary, examines processes responsible for global variability of sea-level records, and presents detailed reviews of sea-level changes for the Pleistocene and Holocene. The book concludes by discussing current trends in sea levels and likely future sea-level changes. This is an important and authoritative resource for academic researchers and graduate and advanced undergraduate students working in tectonics, stratigraphy, geomorphology, physical geography, environmental science and other aspects of Quaternary studies.

Download or read book Pliocene to Quarternary Sedimentary Evolution of Intarmountain Basins at the Junction of Alps Dinarides and Pannonian Basin written by Eva Mencin Gale and published by . This book was released on 2021 with total page 165 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Morphology and Late Quaternary Fill of the Western Alboran Basin Mediterranean Sea written by and published by . This book was released on 1971 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt: ;Contents: Geological framework of the study area; Measurements; Bathymetric survey and its interpretation; Sub-bottom reflectors; Stratification as noted in cores; Lateral continuity of sand and silt layers; Hydrodynamic interpretation of sedimentary features; Sediment dispersal patterns in the Western Alboran Basin; Stratigraphic interpretation of Western Alboran Basin sediments.

Download or read book Numerical Results of the Analysis of Sea bottom Cores Vol 2 written by C. Gehin and published by . This book was released on 1969 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Provenance and Accumulation Rates of Pliocene and Quaternary Sediments from the Western Coral Sea written by Helmut Beiersdorf and published by . This book was released on 1989 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Late Quaternary Sea level Highstands and Deep ocean Circulation Variability During the Mid pliocene Implications for Future Climate Change written by Robert K. Poirier and published by . This book was released on 2017 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Insights Into Pacific Water Column Evolution During the Pliocene and Early Pleistocene Based on Stable Isotopes of Benthic Foraminifera written by Peter Benbenek Kwiek and published by . This book was released on 1998 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Studies in Paleo oceanography written by William Winn Hay and published by . This book was released on 1974 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mediterranean Cold Water Corals Past Present and Future written by Covadonga Orejas and published by Springer. This book was released on 2019-07-10 with total page 582 pages. Available in PDF, EPUB and Kindle. Book excerpt: What do we know about Mediterranean Cold (Deep)-Water coral ecosystems? In this book, specialists offer answers and insights with a series of chapters and short papers about the paleoecology, biology, physiology and ecology of the corals and other organisms that comprise these ecosystems. Structured on a temporal axis—Past, Present and Future—the reviews and selected study cases cover the cold and deep coral habitats known to date in the Mediterranean Basin. This book illustrates and explains the deep Mediterranean coral habitats that might have originated similar thriving ecosystems in today’s Atlantic Ocean.