Saddle dolomite and calcite cements as records of fluid flow during basin evolution: Paleogene carbonates, United Arab Emirates

Pervasive early diagenetic dolomitization, subsequent hydrothermal alteration, and late stage hydrocarbon accumulation in a Middle Triassic carbonate sequence (Szeged Basin, SE Hungary)

“…Hydrothermal dolomitization induced by compressional tectonism is also a well-documented phenomenon (e.g., Ronchi et al, 2012;Sirat et al, 2016;Mansurbeg et al, 2016;Dong et al, 2017); however, in contrast with our interpretation, in the most cases the hydrothermal fluids are identified as basinal brines or mixed magmatic and formational waters.…”

“…The latest pore-filling phases are calcite, quartz, and Cd-3 dolomite, that postdate all the matrix phases and Cd-2 cement, but their timing relative to each other is uncertain. Among these phases, the calcite is most probably meteoric in origin, as it is documented from similar lithologies and geological settings (e.g., Nader et al, 2004;Gomez-Rivas et al, 2014;Sirat et al, 2016;Mansurbeg et al, 2016;Guo et al, 2016;Dong et al, 2017). The observed cathodoluminescence zonation of calcite crystals (Fig.…”

“…The western part of the B-B′ cross-section is based on the interpreted seismic sections of Tari (1999) and Matenco and Radivojević (2012), that are located close to the studied area. Davies and Smith, 2006;Gomez-Rivas et al, 2014;Sirat et al, 2016;Hips et al, 2016;Mansurbeg et al, 2016;Guo et al, 2016;Dong et al, 2017).…”

“…Most of the massive dolostone reservoirs were initially formed by early diagenetic processes that mainly related to seawater (Sun, 1994;Qing et al, 2001;Machel, 2004), however, in recent decades, there is an increasing interest in structurally controlled hydrothermal dolomite bodies due to their excellent potential as reservoirs and hosts to Mississippian Valley-type (MVT) ore deposits (Davies and Smith, 2006). Most documented hydrothermal dolomite reservoirs occur in limestones (Smith, 2006;Davies and Smith, 2006;Ronchi et al, 2012;Gomez-Rivas et al, 2014;Jacquemyn et al, 2014;Sirat et al, 2016; https://doi.org/10.1016/j.marpetgeo.2018.07.024 Received 3 April 2018; Received in revised form 7 July 2018; Accepted 23 July 2018…”

Comparison of the diagenetic and reservoir quality evolution between the anticline crest and flank of an Upper Jurassic carbonate gas reservoir, Abu Dhabi, United Arab Emirates

“…Shift in the chemistry of formation waters from Mg-rich to Ca-rich can be constrained by using T mice and apparent eutectic temperatures of carbonate cements. The T mice (-24.4 and -17.8°C) and apparent eutectic temperatures (-58 to -50°C) of fluid inclusions in blocky calcite (C5) indicate that the brines were highly saline (19.2-25.2 wt% NaCl eq) and contained other salts than NaCl, possibly CaCl 2 (Oakes et al, 1990, Goldstein andReynolds, 1994 Merino and Canals, 2011;Mansurbeg et al, 2016;Sirat et al, 2016).…”