Browsing by Author "Clennell, B"

Now showing 1 - 1 of 1
  • No Thumbnail Available
    Item
    Contrasting anisotropy of velocity and electric/dielectric response in the Marcellus and Utica shales
    (Society of Exploration Geophysicists, 2018-10-28) Delle Piane, C; Josh, M; Dautriat, J; Sarout, J; Giwelli, A; Luzin, V; Clennell, B; Dewhurst, D
    The Marcellus and Utica shales in the USA have become part of the recent shale gas boom, with both shales under increased exploration and production in the past few years. The Marcellus Shale investigated here is clay-rich with a migrated organic component and has undergone significant thermal maturation, probably at temperatures in excess of 250°C (EqVr > 4). The Utica Shale investigated has both carbonate and muddy carbonate facies, also with a migrated organic component at lower thermal maturity (EqVR < 1.8). Velocity anisotropy in the Marcellus is controlled by fracturing as measurements were only possible under ambient conditions. Anisotropy of electrical/dielectric properties was controlled by organic matter maturation, with the high level of maturity resulting in proto-graphite formation and high conductivity. In the Utica shale, velocity anisotropy was controlled by organic matter and calcite alignment in the carbonate facies and clay alignment plus organics in the muddy facies. The Utica shale was highly resistive due to low porosity, low water saturation and the presence of the migrated organic component in the original pore system. © 1996–2023 Society of Exploration Geophysicists