Geologic analysis of the Upper Jurassic Haynesville Shale in east Texas and west Louisiana

Abstract

The Upper Jurassic Haynesville Shale is currently regarded as one of the most prolific emerging shale-gas plays in the continental United States. It has estimated play resources of several hundred trillion cubic feet and per-well reserves estimated as much as 7.5 bcf. The reservoir spans more than 16 counties along the boundary of eastern Texas and western Louisiana. Although this basin has a long history of exploration and analysis of its Mesozoic section, a comprehensive subsurface study characterizing the Haynesville Shale has not been conducted. This article is the first to address the structural setting, stratigraphy, depositional environment and facies, fracturing, and production challenges of the Haynesville shale-gas play.Basement structures and salt movement influenced carbonate and siliciclastic sedimentation associated with the opening of the Gulf of Mexico. The Haynesville Shale is an organicand carbonate-rich mudrock that was deposited in a deep partly euxinic and anoxic basin during the Kimmeridgian to the early Tithonian, related to a second-order transgression that deposited organic-rich black shales worldwide. The Haynesville Basin was surrounded by carbonate shelves of the Smackover and Haynesville lime Louark sequence in the north and west. Several rivers supplied sand and mud from the northwest, north, and northeast into the basin. Haynesville mudrocks contain a spectrum of facies ranging from bioturbated calcareous mudstone, laminated calcareous mudstone, and silty peloidal siliceous mudstone, to unlaminated siliceous organic-rich mudstone. Framboidal to colloidal pyrite is variably present in the form of concretions,

The Environmental Costs and Benefits of Fracking

“…Resource productivity is the key to characterizing how much oil and natural gas will be extracted from an area and for estimating environmental metrics such as the freshwater and GHG intensities of extraction (10)(11)(12). When assessing resource productivity, the productive unit differs for unconventional and conventional plays.…”

Investigation of Fracturing Network Propagation in Random Naturally Fractured and Laminated Block Experiments

“…When a massive fracture system is generated by the interaction of silty laminae and natural fractures during artificial fracturing, theshale reservoir can be fully transformed into an effective stimulated formation of shale-gas aggregation [1,15]. For typical silty laminae structural shale formations, studies were mainly focused on the occurrence of silty laminae [16], depositional environments [17], hydrodynamic conditions [18], origin of silty laminae [19], the shale gas generation and distribution [20]. From the exploration and experimental results of the scholars [12,21], it is obvious that silty laminae forms significant migration conduits and contribute significantly to reservoir storage.…”

The composition and its impact on the methane sorption of lacustrine shales from the Upper Triassic Yanchang Formation, Ordos Basin, China

“…Successful exploration and production of shale gas in USA has greatly encouraged investigations into the composition (both organic and inorganic) and the gas potential of shales from North America and Europe in the past ten years (Bowker, 2007;Bustin, 2007a, 2008a,b;Curtis, 2002;Gasparik et al, 2014;Hammes et al, 2011;Jarvie et al, 2007;Montgomery et al, 2005;Rexer et al, 2013Rexer et al, , 2014Ross and Bustin, 2007Selley, 2012;Strą po c et al, 2010). In the past few years, Chinese geologists have shown increasing interest in the composition and gas potential of shales (Chen et al, 2011;Han et al, 2013;Wang et al, 2013), and shale gas was licensed as a new type of mineral resource by the Chinese Government in 2011 to accelerate the exploration of shale gas.…”