Heavy mineral record of Andean uplift and changing sediment sources across the NE margin of South America: A case study from Trinidad and Barbados
Published:January 01, 2014
Hasley Vincent, Grant Wach, Yawooz Ketannah, 2014. "Heavy mineral record of Andean uplift and changing sediment sources across the NE margin of South America: A case study from Trinidad and Barbados", Sediment Provenance Studies in Hydrocarbon Exploration and Production, R. A. Scott, H. R. Smyth, A. C. Morton, N. Richardson
Download citation file:
The heavy mineral compositions of sandstones in Trinidad and Barbados record the onset of Andean-related erosion and a reduction of craton-derived sediments into NE South America. The changing provenance was deduced by comparing heavy mineral assemblages interpreted from ancient sandstones with associations recognized in modern sands that can be reasonably correlated to existing tectonic domains. The impact of the Andean orogeny across the margin was to introduce a suite of minerals characteristic of low-temperature metamorphism that today is prevalent adjacent to the Caribbean Mountain belt and differs from the zircon-rich assemblage produced within cratonic plains. Twenty-one Paleocene–Late Pliocene sandstone samples from Trinidad revealed systematic changes in mineral diversity and maturity that recorded this provenance transition, and suggests Andean erosion during deposition of the Late Oligocene Nariva Formation. Similar to Palaeogene sandstones of Trinidad, four Eocene Scotland Formation samples from Barbados support craton derivation, but with additional evidence of minor Andean input probably due to the proximity of the Scotland Formation delivery systems to an earlier uplift episode. By the Late Miocene, most of the sediments delivered into Trinidad basins were supplied from the Andean orogeny as suggested by the relative abundance of minerals of this affinity. The heavy mineral records of Trinidad and Barbados are similar to that described across northern South America from both modern and ancient environments that collectively mark the uplift of the Andean mountain belt, with its strong influence on drainage patterns and reservoir provenance along this sector of the continental margin.
Sample location coordinates, sample and outcrop photographs, and summary outcrop sections are available at http://www.geolsoc.org.uk/SUP18728.
Figures & Tables
Sediment Provenance Studies in Hydrocarbon Exploration and Production
Sediment provenance studies concern the origin, composition, transportation and deposition of detritus and therefore are an important part of understanding the links between basinal sedimentation, and hinterland tectonics and unroofing. Such studies can add value at many stages of hydrocarbon exploitation, from identifying regional-scale crustal affinities and sediment dispersal patterns during the earliest stages of exploration, to detailed correlation in producing reservoirs and understanding the impact of mineralogy on reservoir diagenesis.
The volume showcases the wide variety of techniques available, using examples and applications from all aspects of sediment provenance research. The papers are organized into four sets around the following themes:
Overview: applications of provenance information in hydrocarbon reservoir sandstones
Provenance, diagenesis and reservoir quality
Provenance studies linking sediment to source
Looking forward: development of techniques and data handling
This book is dedicated to the memory of Maria Mange and Robert A. Scott.