Fluid Inclusion Microthermometry and Dating of The Quartz Cement within The Upper Nubian Sandstone Reservoir,  SE Sirte Bain, Libya

Sadeg M.  Ghnia; Ali M. Karboub; Abdulsalam M. Almishkhi

doi:10.59743/jmset.v2i1.113

Authors

Sadeg M. Ghnia Department of Geophysics, Faculty of Arts and Science, Al-Mergheb University, Mesallata, Libya.
Ali M. Karboub Exploration Department, Waha Oil Company, Tripoli, Libya.
Abdulsalam M. Almishkhi Department of Marine Geology, Faculty of Marine Resources, Alasmarya Islamic University, Zliten, Libya.

DOI:

https://doi.org/10.59743/jmset.v2i1.113

Keywords:

Upper Nubian Sandstone, Quartz cement, Fluid inclusions microthermometry

Abstract

Quartz cement is the most important cementing agent in the Upper Nubian Sandstone reservoir within the Hameimat trough, SE Sirte Basin. Determining the timing and paleo-pore fluid compositions is important in order to understand the reservoir quality of the Upper Nubian succession. Fluid inclusions microthermometry study, using a modified U.S.G.S. gas flow heating/freezing stage system, together with basin modeling was carried out to determine the time of quartz cementation and paleo-pore fluid compositions. Fluid inclusions study results give a precipitation temperature range of silica cement as 115˚C-128˚C. Investigation of this temperature with burial history curves indicates the onset of quartz overgrowth cementation was in Late Palaeocene probably from through flow of silica-enriched pore fluid. Tice and Teu's measurements indicate that these were complex brines.

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