Late Cenozoic of Península Valdés, Patagonia, Argentina: An Interdisciplinary Approach

BOUZA, P; BILMES, A.

Springer

Lugar: Cham; Año: 2017 p. 314

978-3-319-48507-2

This book presents extensive and new information on the Late Cenozoic record of one of the most important world heritage sites of southern South America: The Península Valdés. From a multidisciplinary approach, that includes geologicaL, biological, paleontological and archeological perspectives, the book describes the main environmental factors and the land and biological processes of this region from the late Cenozoic to the present. The volume brings together an update of the geology, climate, geomorphology, soils, biodiversity, paleontology, archeology of Península Valdés as well as the human impacts on their ecosystems. It includes many published and unpublished information developed mostly by researchers of the Centro Nacional Patagónico (CENPAT) that has never been compiled before.The scope of this book extends to any natural science researcher, graduate student or curious reader of the world interested on the Cenozoic history of Península Valdés.The study region of this book, Península Valdés (Fig.1), is located on the coast of the Argentine Patagonia, between parallels 42°05′ and 42°53′S and meridians 63°05′ and 64°37′W (Fig.1). It covers an area of 3600 km 2, and its limits are the Golfo San Matías (San Matías Gulf) to the north, the Atlantic Ocean to the east and south, and the Golfo Nuevo (Nuevo Gulf) and Golfo San José(San JoséGulf) to the west. Connected to the continent by an isthmus of only 11 km wide and less than 30 km long (Istmo Carlos Ameghino; Carlos Ameghino Isthmus), Península Valdésis almost an island considered a part of the Patagonian steppe, a cool semidesert. It has a dynamic coastal zone with active sand dunes, numerous cliffs, spits, bays and coastal lagoons. The interior of the land is Patagonian desert steppe with dry climate and strong winds. Because the coast and gulfs of Península Valdes are sites of global significance for the conservation of marine mammals (southern right whale, southern elephant seals, southern sea lions and orcas) it was inscribed by UNESCO as a World Heritage Site in 1999. Península Valdés is an almost unpopulated region, except for the presence of a few isolated sheep farms and the touristic location of Puerto Pirámides (Fig.1) on the shore of Golfo Nuevo. This small town, with no more than 500 permanent inhabitants, receives around 200,000 tourists each year due to the attractive proximity to whale-sighting spots.This book is designed to be accessible and practical for readers both familiar and unfamiliar with Península Valdés. It is organized in 11 chapters that are strongly interrelated. The sequence of each chapter was designed in other to support the description of the following chapters and to avoid the repetition of information. In addition, chapters were organized in order to be read separately and include references and a glossary of 10?15 key terms within the chapter. Thus it would be possible both to read the 11 chapters of the book as a whole manuscript or as separated papers.The volume contains many figures and photos, and appendixes of terrestrial living species defined in the area. It also includes seven unpublished thematic maps of Península Valdés, all of them designed at the same scale (e.g., Geomorphological map, Vegetation map, Geohydrological map).Chapter?Climatic, Tectonic, Eustatic and Volcanic Controls on the Stratigraphic Record of Penísnula Valdés?of the book provide a general framework and geodynamic evolution where the Penísnula Valdés is located from the early Paleozoic to the present. It is analysed at different scales how the interplay between climate, tectonic, sea-level and volcanic processes, set the sedimentary routing system that had governed thefinal geologic records of this area.Chapter?Geology of Península Valdés?offers a review of previous geological and paleontological studies in the Península Valdés region and surrounding area since the eighteenth century until present. This section emphasizes the stratigraphic framework (subsurface and surface geology), structural geology, historical geology and the geological resources of Península Valdés.From a Geo-paleontological approach, the Miocene Marine Transgressions of Península Valdés described in Chapter ?Miocene Marine transgressions:Paleoenvironments and Paleobiodiversity? focus on the sedimentary palaoenvironments and paleobiodiversity (palynomorphs, foraminifers, and marine invertebrates, cetaceans, pinnipeds, marine fishes and birds, as well as continental mammals, birds andfishes). This chapter integrates a vast amount of sedimentological and paleontological information and provides, probably for thefirst time, an integrated reconstruction of the paleoenvironmental conditions that the Península Valdés region had experienced during the Miocene.The present climate in Península Valdés is analysed in Chapter?The Climate of Península Valdés Within a Regional Frame?within a regional climate framework to highlight its uniqueness in relation to the rest of north eastern Patagonia. This chapter explains the interplay between large scaled factors and local ones as the almost insularity of the study area. A description is presented through the records of temperature, precipitation and wind and the influence of the oceanic climate. It is shown that although Península Valdés is mostly dominated by the Patagonian arid conditions, its climate has some singularities that make it a less arid and milder climate whit some Mediterranean features.Chapter?Late Cenozoic Landforms and Landscape Evolution of Penísnula Valdés?is focused on the landforms and on the landscape evolution of Península Valdés. This chapter offers a useful tool to understand the Late Cenozoic landscape dynamic of this area. It also represents an indispensable key to understand topics covered in other chapters as soil genesis and distribution, hydrogeological dynamics, vegetation patterns, geo-ecological functions and processes, and distribution of archaeological material.Chapter?Vegetation of Península Valdés: Priority Sites for Conservation? describes the main vegetation units of Península Valdés at a meso-scale with emphasis on relevant physiognomic andfloristic characteristics. Within this frame, dominant vegetation units were identified at a 1:250,000 scale, reflecting the variety of environmental conditions of Península Valdés.The soil?geomorphology relationships and pedogenic processes are described in Chapter ?Soil?Geomorphology Relationships and Pedogenic Processes in Penísnula Valdés?. In this chapter a general discussion on soil parent materials and soil formation processes is presented taking into account the geomorphological setting offered in Chapter?Late Cenozoic Landforms and Landscape Evolution of Penísnula Valdés?to characterize the soil?geomorphic relationships.The soil degradation processes are summarized in Chapter?Soil Degradation in Peninsula Valdes: Causes, Factors, Processes and Assessment Methods?, where a review on the current knowledge of causes, mechanisms, and factors in the Península Valdés rangelands is analysed. Also, this chapter offers a review of soil degradation assessment methods and several soil degradation studies designed in the region.Chapter?Groundwater Resources of Penísnula Valdés? analyses the groundwater resources of Península Valdés in order to established the relation between the late Cenozoic stratigraphy and geomorphology with the hydrogeology and hydrodynamic (recharge, flow, and discharge of groundwater) of the region. The groundwater quality and source are well supported by geochemistry and isotopic compositions, respectively.Chapter?Archaeology of the Penísnula Valdés: Spatial and Temporal Variability in the Human Use of the Landscape and Geological Resources? deals with the archaeology of Península Valdés, focused on two investigative aspects: (1) synthesize the diverse ways in which the native hunting-gatherers used the landscape and its resources through time and (2) the use of mineral resources, mainly rock fragments and soil argillaceous minerals, in the lithic and ceramic technologies, respectively.Finally, Chapter?Animal Diversity, Distribution and Conservation?describes the patterns of biological diversity of the major taxa inhabiting Península Valdés.This chapter summarizes the ecological information available on the species of arthropods, reptiles, terrestrial birds and mammals known to occur at Península Valdés within the context of the Monte and Patagonia eco-regions.In Summary, this book is the result of a collective effort of more than 30 specialists and 24 reviewers. We are extremely thankful for their motivation, persistence, critical analysis and patience. This book represents the state of current understanding and hopefully highlights the enormous potential for future study that the Península Valdés has.Puerto Madryn, Pablo Bouza and Andrés Bilmes, EditorsAugust, 2016