GRANMUD: Granulometric and geochemical contrast comparison of carbonate mud lithified under natural and laborytory conditions
Final Report Abstract
Carbonate ooze, or micrite, its lithified counterpart, forms a main component of limestones throughout Earth History. In ancient carbonate environments, the sources of micrite might be diverse, but without the sedimentological context, the origin of the ooze is difficult to recognize when altered. Micrite isotope data commonly represent a geochemical average of the depositional environment and their origin (platform, slope, water column, authigenic) and mineralogy (aragonite, (Mg-)calcite) and are often poorly constrained. This is because the geochemical and volumetric significance of carbonate precipitates formed during cementation is difficult to assess. Depending on the primary mineralogy, the volume and geochemistry of secondary (micro-)cements and the diagenetic regime (meteoric fluids, marine pore waters, shallow or deep burial settings), the geochemistry and mineralogy of micritic rocks will deviate in variable degrees from the original composition of unconsolidated oozes. In addition, with reference to the secular changes in seawater chemistry, carbonate mineralogy has varied through times. According to the carbonate mode, the mineralogy of carbonate oozes produced in the neritic and pelagic realms will change. Consequently, the original make-up of most ancient micrite is enigmatic and the resulting geochemical record represents an admixture of environmental and diagenetic signals. This study is based on the physical separation of specific grain-classes components of micrite using a granulometric separation method and allows their quantification and characterization in sediments from various geological settings (age, ocean chemistry, margin morphology). In particular, their specific geochemical signatures show the relative significance of the parameters affecting the geochemical composition of bulk samples. The identification of the origin of micritic particles underlines the complex interaction between the mineralogy (pristine or not), the relative proportion of the various micritic grain-classes, the amount of export on the transect and the diagenesis. It is then believed that this work is an important step in the micrite research domain.
Publications
- (2010). Granulometric and geochemical characterization of fossil carbonate oozes: Field studies and precipitation experiments. IAS, Mendoza (Argentina)
Turpin M., Rinder T., Christ N., Dietzel M. & Immenhauser A.
- (2010). Granulometric and geochemical contrast comparison of carbonate mud lithified under natural and laboratory conditions. Exxon FC2 Annual meeting, Leoben (Austria)
Turpin M., Christ N., Rinder T., Dietzel M. & Immenhauser A.
- (2010). Stoichiometric characterization of dolomites by cell and Rietveld refinements (Middle Triassic rocks, French Jura): A new approach. GEO, Manama (Bahrain)
Turpin M., Nader F. & Kohler E.
- (2011). Fossil carbonate oozes characterization in platform to basin transects: Case studies of Carboniferous in Spain and Jurassic in Morocco. IAS, Zaragosa (Spain)
Turpin M., Gressier V., Bahamonde J. R. & Immenhauser A.
- (2011). Granulometry and geochemistry of micritic carbonates along a Carboniferous and a Jurassic platform to basin transects. EGU, Vienna (Austria)
Turpin M., Rinder T., Dietzel M., Bahamonde J. R. & Immenhauser A.
- (2011). Platform to basin transects study for granulometric and geochemical characterization of fossil carbonate oozes. SwissSed, Fribourg (Swiss)
Turpin M., Rinder T., Dietzel M., Christ N., Bahamonde J. R. & Immenhauser A.
- 2011 : Whiting-related sediment export along the Middle Miocene carbonate ramp of Great Bahama Bank. International Journal of Earth Sciences, 100, 1875-1893
Turpin M., Emmanuel L., Reijmer J.J.G. and Renard M.
- (2012). Characterization of micrites along platform to basin transects. Meeting of the Geologisch Vereinigung, Hamburg, Germany
Turpin M., Gressier V., Bahamonde J. R. & Immenhauser A.
- 2012: Empirical calibration for dolomite stoichiometry calculation: Application on Triassic Muschelkalk-Lettenkohle carbonates (French Jura). Oil and Gas Science and Technology-Special volume: “Diagenesis - Fluid- Rocks Interactions”, 67, 1, 77-95
Turpin M., Nader F. and Kohler E.
