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The evolution of the Argentina Continental Margin during the Quaternary and the stratigraphic and morphosedimentary configuration responded to climatic variability, oceanographic changes, glacioeustatic fluctuations and tectono-isostatic processes, which began to impact on the margin during previous geological periods. The final modeling of the margin was achieved in the late Miocene, when the interaction between the Antarctic and North Atlantic water-masses favored climatic and oceanographic changes with a profound effect on morphosedimentary features. In the Quaternary, the different regions of the margin distinctly responded to such changes. Whereas in the shelf the main modeling factors were the sea-level fluctuations of glacioeustatic origin and consequent marine-continental stratigraphic records, in the slope (particularly in the sector corresponding to the passive margin) the prevailing effect was the interaction between water-masses and the sea floor, giving origin to contouritic depositional systems accompanied of gravity processes responsible of turbiditic and mass-wasting deposits. Different relationships between contouritic and turbiditic facies respond to distinct combinations of oceanic circulation variability and the indirect effect on the sea floor of sea-level fluctuations.
As a result of this complexity in the regional processes in the framework of the broad hemispheric oceanographic-climatic conditioning factors, the ACM can be considered as a complete archive for the Southern Ocean.

Inhaltsverzeichnis

Frontmatter

Chapter 1. Introduction

Abstract
This chapter introduces to the subjects that will be discussed throughout this book, from the concepts and significance of continental margins to the importance of the Argentine margin in the framework of the global climatic–oceanographic coupling.
Roberto A. Violante, Cecilia Laprida, Natalia L. García Chapori

Chapter 2. Continental Margins in the Global Context

Abstract
As highly significant features of major order at the lands–oceans edge, continental margins play an exceptional role in the Earth system. They are relevant for understanding the continental drift and the birth of oceans, the endogenous and exogenous processes that regulate the planet evolution, the present and past climatic and oceanographic changes, and the carbon cycle and biogeochemistry of the Earth. On this basis, the importance of those features at a global scale is discussed. This chapter also provides the basic definitions needed for understanding the concept of continental margins.
Roberto A. Violante, Cecilia Laprida, Natalia L. García Chapori

Chapter 3. The Argentina Continental Margin: Location and Significance

Abstract
The Argentina Continental Margin (ACM) is one of the largest margins on the Earth. It is located in a key region of the World Ocean that is highly significant in the planet’s oceanographic-climatic system. The evolution of the Argentine margin is explained in terms of the combination and interaction among geotectonic, oceanographic and climatic factors. Because of that evolution, four types of margins develop in the region: a passive-volcanic rifted, a transcurrent-sheared, a mixed and an active margin. These aspects determine particular tectonic and stratigraphic characteristics for each of them.
Roberto A. Violante, Cecilia Laprida, Natalia L. García Chapori

Chapter 4. Morphosedimentary Configuration of the Argentina Continental Margin

Abstract
The major regional features of the margin are coastal plains, shelf, slope and rise. These features show varied characteristics depending on their location on each type of margin. They contain diverse subordinated morphosedimentary features related to the prevailing genetic processes acting on each of them and shaping their relief. The shelf is shaped in terraces at increasing stepping depths toward offshore, they having been genetically related to fluctuations in the sea-level rise during the post-glacial transgression. The slope is also shaped in terraces, but in this case, these features are genetically associated to the development of alongslope complex systems of mixed depositional and erosive contouritic features formed at different depths, possibly related to highly energetic interfaces between adjacent water masses that constitute the thermohaline oceanic system. Gravitational, downslope processes generating turbidites, mass transport and debris flows deposits, most of them acting inside or close to submarine canyons, actively interact with the contouritic processes. The rise is partially formed by gravity-driven deposits at the base of the slope, although in the southern part of the margin the alongslope, contouritic processes are strong enough to shape the rise and imprinting it with particular current-driven features.
Roberto A. Violante, Cecilia Laprida, Natalia L. García Chapori

Chapter 5. Climate and Oceanographic Background

Abstract
The regional climatic and oceanographic characteristics that regulate the climate-ocean system in the region are explained. The climatic system has different features depending on regional and local forcings, such as the Intertropical Convergence Zone, the South American Monsoon System, the Southern Hemisphere Westerlies, and the South Atlantic Convergence Zone. The hydrographic structure is dominated by different water-masses of Antarctic and Tropical origin, related to the major circulation system of the Western South Atlantic linked to the Atlantic Meridional Overturning Circulation. The main water-masses constituting the hydrographic structure are the Tropical Water-South Atlantic Central Water, the Antarctic Intermediate Water, the North Atlantic Deep Water and the Antarctic Bottom Water, being most of the Antarctic-sourced water-masses genetically related to the circulation of the Antarctic Circumpolar Current.
Natalia L. García Chapori, Cecilia Laprida, Roberto A. Violante

Chapter 6. Principles of Paleoceanographic Reconstruction

Abstract
This chapter introduces the principles of paleoceanographic reconstructions and proxy data, focusing on the concepts of climatic, biological, geological, geochemical as well as other large-scale proxies, tracers and records useful for such reconstructions in the western South Atlantic. Different proxies particularly useful for the Argentine margin, including physical and chemical properties of sediments, microfossils and geochemical and isotopic properties, are described.
Cecilia Laprida, Natalia L. García Chapori, Roberto A. Violante

Chapter 7. State of the Art in the Paleoceanographic Reconstructions at the Argentina Continental Margin

Abstract
The characteristics of the Argentina Continental Margin, particularly depending on its key location in the climate and oceanographic global system, make it to have a high potential for paleoclimatic, paleoceanographic and paleoenvironmental reconstructions. An overview of the present knowledge of the matter, given by the application of a varied set of proxies and tracers in different regions of the margin, like the shelf and the slope, is detailed.
Cecilia Laprida, Natalia L. García Chapori, Roberto A. Violante

Chapter 8. Conclusions

Abstract
This chapter stresses the importance of the Argentine Margin as a potential source for paleoceanographic and paleoclimatic reconstructions in the Southern Ocean, and sets the basis of the knowledge needed for future research in the region.
Roberto A. Violante, Cecilia Laprida, Natalia L. García Chapori
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