AbstractsEarth & Environmental Science

Geophysical Analysis of Quaternary Marine Sedimentary Processes, Bonaire, Netherlands Antilles

by Mary Kathryn Bales

Institution: Texas A&M University
Year: 2016
Keywords: geophysics; seismic; carbonate; Bonaire; isolate carbonate platform; sedimentary processes
Posted: 02/05/2017
Record ID: 2064427
Full text PDF: http://hdl.handle.net/1969.1/158090


The island of Bonaire is an isolated carbonate platform that is formed of Miocene to modern carbonate successions overlying a Cretaceous igneous basement. We show that the igneous basement of the island of Bonaire, Netherland Antilles controls the seafloor topography and subsequently governs the location of most of the carbonate deposits especially the Holocene coral reef and the downslope transport of sediment. Our analysis from this combined sedimentary study focuses on: 1) identifying the source of the islands main sediment supply, where sediment is derived from and quantifying the sediment budget; 2) evaluating the main sediment transport mechanisms throughout the system and indicating the most influential factor; 3) assessing sediment transport from the coast to the basin by identifying sediment pathways and their morphology; and 4) locating sediment accumulation zones in all areas of the offshore environment. To archive our objectives, we acquired ~172 km of 2D multichannel seismic reflection profiles on the western side of Bonaire to evaluate the marine environment off the coast of this isolated carbonate platform. By the integration of previous studies, both geological and geophysical, in addition to an assessment of Quaternary marine sedimentary processes within the system, we focus on the slope processes including sediment production and distribution. Production from both terrigenous and marine sources as well as transport mechanisms including mass transport and gravity driven downslope movement are studied. This study highlights the importance of understanding the morphology of the antecedent substrate on which a carbonate environment is produced and how the climate and environment of Bonaire play a large role in sediment transport throughout our local system. The sediment processes observed in our study reveal contributing factors to the persistent carbonate production offshore Bonaire throughout the Quaternary and provide a modern analogue for other isolated carbonate platforms. Advisors/Committee Members: Reece, Robert (advisor), Laya, Juan Carlos (committee member), Klaus, Adam (committee member).