The Neuquén Basin, Argentina: A Case Study in Sequence Stratigraphy and Basin Dynamics

VEIGA, G.D., SPALLETTI, L.A., HOWELL, J.A., Y SCHWARZ, E.

The Geological Society

Lugar: Bath; Año: 2005 p. 336

1-86239-190-4

Preface The aims of this special publication are to present the geological history of the spectacular Neuquén Basin. It is envisaged that this book will act as both an introduction to the Basin and also as a focus for recent developments in the long history of its study. Furthermore we hope that the book goes further than just presenting the latest studies on a specific area. We have aimed to present an integrated case study in sequence stratigraphy, palaeontology and basin analysis, lessons from which have implications for systems worldwide. The concept of this book was born in the field in Argentina. We felt that there was a need to provide high quality case studies that integrate different aspects of basin evolution and sequence stratigraphy and we felt the Neuquén Basin provided such a dataset. However, it was apparent that although the excellent outcrops, the fascinating geology and the number of groups working on many different aspects of the Basin it was not well known within the wider geological community. Despite the remoteness of much of the region, many studies have been undertaken. Some of these have been driven by the prolific hydrocarbons found in the Basin. Others capitalise on the Basin’s unique palaeontogical record while the region has also been used for detailed sequence stratigraphic and facies-based studies which utilise the excellent outcrops as analogues for subsurface reservoirs both within the Basin and internationally. Structural studies on the fold and thrust belt are central to understanding the evolution of the basin and the Andean margin of Gondwana. The structural history of the basin records the change from Late Triassic extension through Jurassic and Early Cretaceous thermal subsidence to middle Cretaceous foreland basin subsidence followed by Andean compression and uplift. Most recent stages of the evolution include the emplacement and extrusion of a variety of igneous suites. The basin-fill succession includes deep-marine turbidite, hemi-pelagic and pelagic systems; shallow-marine clastic and carbonate systems; evaporites; a variety of different fluvial systems and several phases of aeolian deposition. Facies contacts such as aeolian sandstones packages within ammonite-bearing offshore shales are testament to a dramatic relative sea-level history, much of which is linked the tectonic evolution of the Andes. The succession also contains one of the World’s most important Mesozoic fossil records. The vertebrate record includes numerous finds of marine and terrestrial reptiles, many of which are unique. Less spectacular but of comparable importance is the most complete southern hemisphere Mesozoic invertebrate record. We hope that this Book provides an insight into this amazing area. In compiling this collection of papers we have aimed to illustrate how all aspects of the geology are interlinked and how all should be considered together.