Fluid flow reconstruction in hanging and footwall carbonates: compartmentalization by Cenozoic reverse faulting in the Northern Oman Mountains (UAE)
Breesch, L.; Swennen, R.; Vincent, B. (2009). Fluid flow reconstruction in hanging and footwall carbonates: compartmentalization by Cenozoic reverse faulting in the Northern Oman Mountains (UAE). Mar. Pet. Geol. 26(1): 113-128. https://dx.doi.org/10.1016/j.marpetgeo.2007.10.004 In: Marine and Petroleum Geology. Elsevier: Guildford. ISSN 0264-8172; e-ISSN 1873-4073, more | |
Keyword | | Author keywords | Reverse fault; Veins; Diagenesis; Fluid flown; Compartmentalization |
Authors | | Top | - Breesch, L., more
- Swennen, R., more
- Vincent, B.
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Abstract | In this paper. the diagenesis from either side of a major Cenozoic reverse fault in the Northern Oman Mountains is documented. Detailed petrographical and geochemical analysis of calcite-filled fractures in carbonate strata of Late Triassic and Early Cretaceous age in the hanging wall and footwall in Wadi Ghalilah reflect a different diagenetic history. In both hanging wall and footwall most of the fractures are pre-burial, extensional in origin, formed by a crack-seal mechanism, and the calcite vein infill has a host-rock buffered signature. In the hanging wall, the fluid responsible for calcite precipitation of these extensional fractures was a marine fluid at 60 degrees C. These veins predate deep burial and contractional tectonic deformation and consequently do not provide any information about syntectonic fluid flow. Neither do the pre-burial extension fractures in the footwall which are also host-rock buffered. The fractures postdating the tectonic stylolitization in the footwall, by contrast. show evidence of syntectonic migration of saline formation waters at temperatures between 80 and 160 degrees C during contractional deformation. These fluids probably were sourced from the Subsurface via the reverse fault. which acted as a fluid conduit. At the same time, however, this fault functioned as a permeability barrier towards the hanging wall. since no evidence of syntectonic fluid flow is present here. In this way compartmentalization of the hanging wall and footwall block was realized. |
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