Burial and exhumation history of Pennsylvanian strata, central Appalachian basin: an integrated study

Abstract

An inferred burial and exhumation history of Pennsylvanian strata in the central Appalachian foreland basin is constrained by integrating palaeothermometers, geochronometers and estimated palaeogeothermal gradients. Vitrinite reflectance data and fluid inclusion homogenization temperatures indicate that burial of Lower and Upper Pennsylvanian strata of the Appalachian Plateau in West Virginia exceeded ∼4.4 km during the late Permian and occurred at a rate of ∼100 m Myr−1. Exhumation rates of ∼10 m Myr−1 from the late Permian to the early Cretaceous are constrained using maximum burial conditions and published apatite fission track (AFT) ages. AFT and radiogenic helium ages indicate exhumation rates of ∼30–50 m Myr−1 from the early to late Cretaceous. Radiogenic helium dates and present day sampling depths indicate that exhumation rates from the late Cretaceous to present were ∼25 m Myr−1. Exhumation rates for Upper and Lower Pennsylvanian strata within the Appalachian Plateau are remarkably similar. Early slow exhumation was possibly driven primarily by isostatic rebound associated with Triassic rifting. The later, more rapid exhumation can be attributed to thermal expansion followed by lithospheric flexure related to sediment loading along the passive margin.

Quantifying Cretaceous–Cenozoic exhumation in the Otway Basin, southeastern Australia, using sonic transit time data: Implications for conventional and unconventional hydrocarbon prospectivity

“…In a study of variations in joint intersection style observed in Middle and Upper Devonian shales within the Appalachian Basin, Lash and Engelder (2009) concluded that the propagation of east-northeast-striking joints happened during two distinct phases during the evolution of the basin, as opposed to solely in response to fluid overpressures during maximum burial that occurred during the Late Permian (Blackmer et al, 1994;Reed et al, 2005). Initial fluid-driven east-northeaststriking joints formed during the early stages of the Alleghanian orogeny (Lash and Engelder, 2009), which were then reactivated under the coaxial contemporary stress regime (S Hmax , ∼072°± 6°; Plumb and Cox, 1987) through a combination of thermal contraction, Poisson's contraction, and/or lateral strain caused by rapid exhumation during the late Miocene (Lash and Engelder, 2009).…”

“…The Upper Cretaceous Mesaverde Group in the southern Piceance Basin was exhumed by approximately 1800 m (∼5905 ft) during the Neogene (Nuccio and Roberts, 2003;Fall et al, 2012), whereas Pennsylvanian strata in the central Appalachian Basin have been exhumed by approximately 4400 m (∼14,435 ft) since the Late Permian (Blackmer et al, 1994;Reed et al, 2005). Although the timing of exhumation from maximum burial depths in the Fort Worth Basin is a matter of some debate (e.g., mid-Cretaceous; Montgomery et al, 2005;Late Triassic;Ewing, 2006), it is agreed that the Mississippian Barnett Shale has experienced more than 1500 m (∼4920 ft) of net exhumation (Jarvie et al, 2005Montgomery et al, 2005;Ewing, 2006).…”

“…Although most previous studies have focused on the impact of exhumation on conventional petroleum systems, some of the most prospective shale gas and tight gas plays in the United States clearly have also been subject to major exhumation. These include the Mississippian Barnett Shale in the Fort Worth Basin (exhumation, >1500 m [∼4920 ft]; Jarvie et al, 2005Jarvie et al, , 2007Montgomery et al, 2005;Ewing, 2006), the Upper Cretaceous Mesaverde Group in the southern Piceance Basin (∼1800 m [∼5905 ft]; Nuccio and Roberts, 2003;Fall et al, 2012), and Pennsylvanian and older plays in the central Appalachian Basin (∼4400 m [∼14435 ft]; Reed et al, 2005). Deeper burial and subsequent exhumation in these basins have brought thermally mature, embrittled shales with substantial secondary porosities and higher hydraulic fracture stimulation potential closer to the surface (Bowker, 2003;Jarvie et al, 2007;Gale et al, 2010).…”

Post‐orogenic thermal history and exhumation of the northern Appalachian Basin: Low‐temperature thermochronologic constraints

“…Utilizing a combination of maximum paleotemperatures indicators, subsidence and thermal modeling, and geologic constraints, deposition of the sedimentary overburden and maximum temperatures likely occurred sometime between the Alleghenian Orogeny in the late Paleozoic and the Early Jurassic (e.g. Johnsson, ; Levine, ; Beaumont, Quinlan, & Hamilton, ; Reed et al, ; Lash & Blood, ).…”

“…temperature and timing), cooling rates, exhumation histories, and hydrocarbon source rock maturation levels within sedimentary basins (e.g. Green, Duddy, Gleadow, & Lovering, ; Naeser, Naeser, & McCulloh, ; Gallagher, Brown, & Johnson, ; Reed, Spotila, Eriksson, & Bodnar, ; Green & Duddy, ; Ketcham, ; Malusà & Fitzgerald, ). AFT thermochronology applied to sedimentary basin strata has the potential to determine maximum paleotemperatures up to ~100–120°C, as well as constrain the timing and rates of cooling (e.g.…”