Project

Back to overview

Sea-level and climate events during the past 5 million years: the record from fossil reefs, coastal deposits and dolostones from Mayaguana and Little Inagua Islands, SE Bahamas

English title Sea-level and climate events during the past 5 million years: the record from fossil reefs, coastal deposits and dolostones from Mayaguana and Little Inagua Islands, SE Bahamas
Applicant Kindler Pascal
Number 124608
Funding scheme Project funding
Research institution Département des sciences de la Terre Université de Genève
Institution of higher education University of Geneva - GE
Main discipline Geology
Start/End 01.04.2009 - 31.03.2012
Approved amount 187'063.00
Show all

All Disciplines (7)

Discipline
Geology
Palaeontology
Geochronology
Other disciplines of Earth Sciences
Mineralogy
Geochemistry
Geophysics

Keywords (17)

physical stratigraphy; sedimentology; sedimentary petrography; radiometric dating; isotope chemistry; high-resolution seismics; sea-level changes; paleoclimatology; dolomitization; Bahamas; late Cenozoic; coral reefs; Cenozoic; climate change; sea-level change; stratigraphy; dolomite

Lay Summary (English)

Lead
Lay summary
Fossil reefs and coastal deposits contain direct information on sea-level and climate fluctuations during the late Cenozoic that supplement data derived from the study of deep-sea sediments and ice cores. Such knowledge is critical to decipher the mechanisms of sea-level and climate variations, and better constrain future global changes. Fossil reefs are precise indicators of former sea stands and can further be accurately dated with the U-series method. The sedimentological and petrographic characteristics of ancient coastal deposits register high-frequency sea-level and water-table changes, as well as climatic conditions during early diagenesis. These deposits may all undergo phases of dolomitization. This is interesting per se (e.g. because dolomitization changes the reservoir properties of parent rocks), but also because the mode of dolomitization is constrained by the degree of carbonate-platform flooding. Dolostones may thus provide also information regarding ancient climate and sea-level fluctuations. Fossil reefs and coastal deposits have been already studied in details in Bermuda, Barbados, Florida, and the northern Bahamas. The basic framework of middle/late Quaternary sea-level and climate changes in these areas is rather well established, but many uncertainties still remain regarding earlier time periods. By contrast, the southeastern Bahamas have not been much studied in this respect, possibly because of their relative inaccessibility. During our first expedition to the SE Bahamas in 2007, we discovered one large reef tract of last interglacial age, widespread lower Pleistocene coastal deposits, and outcropping, massive Miocene and Pliocene dolostones on the surface of Mayaguana Island. The spatial distribution of these exposures suggests that the internal architecture of this small platform must be indeed complex. We therefore intend to focus our study on the nature and geometry of these newly discovered rock units.In addition to refining our understanding on the timing of key sea-level and climate events during the late Cenozoic, a critical piece of information for better resolving the dynamics of ice ages, this study will enable us to complement existing knowledge on coastal sedimentation, dolomitization processes, and the architecture of small carbonate platforms. This first topic is becoming a key scientific and political issue in the current context of anthropogenic global warming and sea-level rise; the other two pertain to rock reservoir properties, which is fundamental for oil exploration and CO2 storage.
Direct link to Lay Summary Last update: 21.02.2013

Responsible applicant and co-applicants

Employees

Name Institute

Publications

Publication
The paradoxical occurrence of oolitic limestone on the eastern islands of Great Bahama Bank: where do the ooids come from?
Kindler Pascal, Hine Albert C. (2012), The paradoxical occurrence of oolitic limestone on the eastern islands of Great Bahama Bank: where do the ooids come from?, Wiley-Blackwell, Chichester, 113-122.
New U/Th and amino-acid racemization dating of Pleistocene sequences from West Caicos Island (SE Bahamas): Implication for cyclostratigraphy.
Kindler Pascal, Meyer Aurélien (2012), New U/Th and amino-acid racemization dating of Pleistocene sequences from West Caicos Island (SE Bahamas): Implication for cyclostratigraphy., in D.G. Gamble and P. Kindler (ed.), Gerace Research Center, San Salvador, Bahamas, 82-95.
Géologie de Mayaguana, SE de l'archipel des Bahamas
Godefroid Fabienne (2012), Géologie de Mayaguana, SE de l'archipel des Bahamas, in Terre & Environnement, 108, 1-230.
Discovery of Miocene to early Pleistocene deposits on Mayaguana, Bahamas: Evidence for recent active tectonism on the North American margin
Kindler P, Godefroid F, Chiaradia M, Ehlert C, Eisenhauer A, Frank M, Hasler CA, Samankassou E (2011), Discovery of Miocene to early Pleistocene deposits on Mayaguana, Bahamas: Evidence for recent active tectonism on the North American margin, in GEOLOGY, 39(6), 523-526.
ESPP Bahamas workshop guidebook: Modern and Quaternary carbonaste environments
Kindler Pascal, Godefroid Fabienne, Curran H. Allen, Dupraz Christophe, Mylroie John E., Strasser André, Verrecchia Eric P. (2011), ESPP Bahamas workshop guidebook: Modern and Quaternary carbonaste environments.
Mineralogical evidence for a local volcanic origin of the parent material of Bermuda Quaternary paleosols
Prognon F, Cojan I, Kindler P, Thiry M, Demange M (2011), Mineralogical evidence for a local volcanic origin of the parent material of Bermuda Quaternary paleosols, in QUATERNARY RESEARCH, 75(1), 256-266.
Further evidence for a +20 m sea-level highstand during Marine Isotope Stage 11 from fossil lacustrine sediments: Glass Window, Eleuthera, Bahamas
Godefroid Fabienne, Kindler Pascal, Nawratil de Bono Carole (2010), Further evidence for a +20 m sea-level highstand during Marine Isotope Stage 11 from fossil lacustrine sediments: Glass Window, Eleuthera, Bahamas, in J.B. Martin and F.D. Siewers (ed.), Gerace Research Center, San Salvador, Bahamas, 90-106.
Geology of Central Eleuthera, Bahamas: a field trip guide.
Kindler Pascal, Mylroie John E., Curran H. Allan, Carew Jim L., Gamble Doug. W., Rothfus Tom A., Savarese M., Sealey N.E. (2010), Geology of Central Eleuthera, Bahamas: a field trip guide..
Soil colluvium and elevated fossil algal-microbial mat near Alice Town (Eleuthera, Bahamas): possible evidence for extreme events and a high sea level during the middle Holocene
Godefroid Fabienne, Kindler Pascal, Samankassou Elias (2010), Soil colluvium and elevated fossil algal-microbial mat near Alice Town (Eleuthera, Bahamas): possible evidence for extreme events and a high sea level during the middle Holocene, in J.B. Martin and F.D. Siewers (ed.), Gerace Research Center, San Salvador, Bahamas, 75-89.

Scientific events



Self-organised

Title Date Place
15th Symposium on the Geology of the Bahamas and other carbonate regions 17.06.2010 Gerace Research Center, San Salvador, Bahamas

Knowledge transfer events



Self-organised

Title Date Place
ESPP Bahamas workshop 2011: Modern and Quaternary carbonate environments 05.02.2011 Gerace Research Center, San Salvador, Bahamas

Communication with the public

Communication Title Media Place Year
Other activities Nuit de la Science 2010 Western Switzerland 03.07.2010

Associated projects

Number Title Start Funding scheme
113356 Sea-level and climate events during the past 500'000 years: the record from fossil reefs, coastal deposits and paleosols from the southeastern Bahamas 01.04.2007 Project funding
140420 Sea-level and climate events during the past 30 million years: the record from fossil reefs, coastal deposits and dolostones from Mayaguana, Great Inagua, Crooked and Acklins Islands, SE Bahamas 01.06.2012 Project funding
113356 Sea-level and climate events during the past 500'000 years: the record from fossil reefs, coastal deposits and paleosols from the southeastern Bahamas 01.04.2007 Project funding

Abstract

1. RESEARCH SUMMARYFossil reefs, coastal deposits (i.e. ancient beaches, eolianites) contain direct information on sea-level and climate fluctuations during the late Cenozoic that supplement data derived from the study of deep-sea sediments and ice cores. Such knowledge is critical to decipher the mechanisms of sea-level and climate variations, and better constrain future global changes. Fossil reefs are precise indicators of former sea stands and can further be accurately dated with the U-series method. The sedimentological and petrographic characteristics of ancient coastal deposits register high-frequency sea-level and water-table changes, as well as climatic conditions during early diagenesis. These deposits may all undergo phases of dolomitization. This is interesting per se (e.g. because dolomitization changes the reservoir properties of parent rocks), but also because the mode of dolomitization is constrained by the degree of carbonate-platform flooding. Dolostones may thus provide also information regarding ancient climate and sea-level fluctuations.Fossil reefs and coastal deposits have been already studied in details in Bermuda, Barbados, Florida, and the northern Bahamas. The basic framework of middle/late Quaternary sea-level and climate changes in these areas is rather well established, but many uncertainties still remain regarding earlier time periods. By contrast, the southeastern Bahamas have not been much studied in this respect, possibly because of their relative inaccessibility. We have started to bridge this gap by undertaking detailed stratigraphic, sedimentological and geochemical analyses of the coastal sediments and reefal terraces exposed in this region. Initially, we planned to focus our research on the climate and sea-level history during three main time intervals: Marine Isotope Stage (MIS) 11, MIS 7, and MIS 5e, and also on the parent material of Bahamian paleosols, which could have provided information on past atmospheric circulation patterns. During our first expedition to the SE Bahamas in 2007, we discovered one large reef tract of last interglacial age, widespread lower Pleistocene coastal deposits, and outcropping, massive Miocene and Pliocene dolostones. We now intend to shift the focus of our study to these objects, the latter two representing opened windows to earlier periods of Earth’s history.In addition to refining our understanding on the timing of key sea-level and climate events during the late Cenozoic, a critical piece of information for better resolving the dynamics of ice ages, this study will enable us to complement existing knowledge on coastal sedimentation and dolomitization processes. This first topic is becoming a key scientific and political issue in the current context of anthropogenic global warming and sea-level rise; the second one pertains to rock reservoir properties, which is fundamental for oil exploration and CO2 storage.
-