Sedimentology and Reservoir characterization of Pirkoh Formation in well-1 Guddu E.L Sindh, Pakistan
Abstract
Sedimentology and reservoir characteristics of Pirkoh Formation of Middle Eocene have been carried out in well -1 of Guddu E.L. by studying the two cores and well cuttings samples. Pirkoh Formation was the primary objective reservoir in this well. It consist of entirely limestone penetrated in well with thickness of 102m. Two cores were cut from this formation (590-599m, 625-634m) and also incorporated in this study. The sedimentological investigation of cores and well cuttings of Pirkoh Formation revealed that it is mainly Wackestone-Packstone facie with larger benthics Forams (LBF) assemblages, consist of Discocyclina and Nummulite sp. in abundance. The Discocyclinoids Wackestone-Packestone facie along with micrite groundmass suggests that it was deposited over middle ramp settings. The presence of Discocyclina and Nummulites along with bioclasts of same microfossil suggests deposition under relatively high energy conditions over the ramp. The paleoecological attributes of Discocyclina and Nummulites also confer same environments. Micrite is the major ground mass matrix in the petrographic analysis which suggests relatively deep environment for its deposition most probably in Middle ramp settings.
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