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,

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The Kamloops Group is redefined as an assemblage of Lower to Middle Eocene volcanic and sedimentary rocks widespread in south-central British Columbia. In the type area west of Kamloops, the basal Tranquille Formation consists of 500 m of lacustrine and deltaic sediments, pillowed flows, and hyaloclastites. Elsewhere, basal coal-bearing nonvolcanic fluvial and lacustrine units occur, such as the Coldwater Formation at Merritt, the Chu Chua Formation at Barriere, and the Shorts Creek Formation west of Vernon. Overlying these formations are dominantly volcanic units. At the type area, the Dewdrop Flats Formation includes over 1000 m of interstratified basaltic andesite flows, andesitic flow-breccia sheets and cones, basaltic tuff rings, and an andesitic composite cone. Elsewhere, flat-lying basaltic andesite flows about 600 m thick with local flow breccias are common.The basal sediments accumulated in separate fault-bounded basins initiated immediately before the onset of volcanism. These volcanic rocks filled the basin and formed a widespread volcanic blanket, which was disrupted by continued fault movement. The numerous basins are linked by a throughgoing fault network with up to 12 km of net right-lateral strike-slip displacement.

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