Exploring the hydrochemical evolution of brines leading to sylvite precipitation in ancient evaporite basins.

Simple item page
dc.contributor.authorCendón, DIen_AU
dc.contributor.authorPueyo, JJen_AU
dc.contributor.authorAyora, Cen_AU
dc.contributor.authorGarcía-Veigas, Jen_AU
dc.contributor.authorBlanc-Valleron, MMen_AU
dc.date.accessioned2010-08-24T04:18:17Zen_AU
dc.date.available2010-08-24T04:18:17Zen_AU
dc.date.issued2010-05-02en_AU
dc.date.statistics2010-05-02en_AU
dc.description.abstractSylvite is a very common mineral in ancient evaporite deposits. Due to the absence of current deposits, the natural geochemical mechanism/s for synsedimentary sylvite precipitation and accumulation are not well understood. Numerous sylvite deposits or portions of them have been described as a result of diagenesis (i.e. Sergipe subbasin, Brasil). However, a number of deposits have been described as synsdimentary or being formed during primary evaporite deposition. It is the last group of deposits that can be studied to better understand the hydrochemical processes taking place in the brine at the onset of sylvite precipitation. The Salt IV sylvite beds from the Mulhouse potash basin, Alsace (France) have been described as synsedimentary in origin (LOWENSTEIN and SPENCER, 1990; CENDON et al., 2008). While sylvite in itself does not contain fluid inclusions viable for micro analysis, primary textures in neighboring halite are used as a proxy to understand brine evolution. Two halite-sylvite cycles from the B1 and B2 layers of the potash lower seam were selected. These exhibited clear primary halite crystal textures with sylvite adapting to an irregular halite sedimentary surface and finishing with a flat surface. The nine halite samples, selected at centimeter scale, provided close to 100 single fluid inclusion analyses, representing both the transition towards sylvite precipitation and the post sylvite precipitation. The fluid inclusion analyses revealed strong fluctuations in K concentration, well over the analytical error (<10%). These variations, in the same halite crystal, seem aligned in growth bands, with fluid inclusions within a certain growth band showing practically identical K concentrations, while neighboring bands exhibit a different concentration. Overall, the closer we are from a sylvite layer the higher K concentrations are. However, strong fluctuations continue when growth bands are compared. This pattern shows cycles of increasing K concentration along parallel growth bands with sharp falls followed by the initiation of a new increasing trend. The small “growth band” scale of the K concentration variations, suggests very sensitive processes within the brine with potential environmental changes (i.e. seasonal variations, day-night temperature fluctuations cycles) leading towards the final mass precipitation of a sylvite layer. © Author(s) 2010en_AU
dc.identifier.articlenumberEGU2010-3807-1en_AU
dc.identifier.booktitleGeophysical Research Abstractsen_AU
dc.identifier.citationCendón, D., Pueyo, J. J., Ayora, C., García-Veigas, J., & Blanc-Valleron, M. M. (2010). Exploring the hydrochemical evolution of brines leading to sylvite precipitation in ancient evaporite basins. Abstract presented to the 7th European Geosciences Union (EGU) General Assembly, 2nd – 7th May 2010. Vienna, Austria: Austria Center. In Geophysical Research Abstracts, 12, EGU2010-3807-1.en_AU
dc.identifier.conferenceenddate7 May 2010en_AU
dc.identifier.conferencename7th European Geosciences Union (EGU) General Assemblyen_AU
dc.identifier.conferenceplaceVienna, Austriaen_AU
dc.identifier.conferencestartdate2 May 2010en_AU
dc.identifier.govdoc2536en_AU
dc.identifier.urihttp://apo.ansto.gov.au/dspace/handle/10238/2337en_AU
dc.identifier.volume12en_AU
dc.language.isoenen_AU
dc.publisherCopernicus Publicationsen_AU
dc.subjectBrinesen_AU
dc.subjectEvaporitesen_AU
dc.subjectSedimentary basinsen_AU
dc.subjectPrecipitationen_AU
dc.subjectDepositsen_AU
dc.subjectHaliteen_AU
dc.titleExploring the hydrochemical evolution of brines leading to sylvite precipitation in ancient evaporite basins.en_AU
dc.typeConference Abstracten_AU
Files
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
CENDON_Exploring_Hydrochemical_Evolution_Brines_2010_5_2.pdf
Size:
47.83 KB
Format:
Adobe Portable Document Format
Description:
Download
License bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
license.txt
Size:
1.71 KB
Format:
Item-specific license agreed upon to submission
Description:
Download
Collections
Conference Publications