Lithofacies Analysis of Two Marcellus Wells Using Core and Log Data in Northern West Virginia, USA

Abstract

Two continuous cores from the dry gas producing region of the Marcellus Shale in Monongalia County, West Virginia are analyzed to better understand the vertical and lateral changes in lithology over short distances in the Marcellus. The two wells, part of the Marcellus Shale Energy and Environmental Laboratory (or MSEEL) are separated by approximately 8.5 miles (13.7km). MSEEL is a large project that has spanned multiple years, involving industrial partners, state agencies and the National Energy Technology Laboratory of the US Department of Energy. The two wells are the vertical pilots for Boggess 17H and MIP-3H wells. The MIP-3H (API: 47-061-01707-00-00) well was drilled and cored in 2015, 112 feet (34m) of core was taken between depths of 7445 to 7557 feet. The Boggess 17H (API: 47-061-01812-00-00) well was drilled in 2019 and 139 feet (42m) of core was recovered. A full suite of triple combo, image logs, and advanced logging tools were run in both wells and calibrated to core analysis. Core analysis includes full CT-scans, mineralogy and chemostratigraphy from XRF and XRD, and determination of total organic content (TOC). Preliminary well log comparisons show that the Boggess 17H well has multiple intervals of higher gamma response in the Marcellus and overlying formations. Integrated geological and petrophysical characterization of the Marcellus and adjacent Onondaga Limestone through Mahantango Formation will use all available core sidewall core and well log data to determine variations in macro-scale and mesoscale lithofacies. Understanding the vertical and lateral distribution of the shale lithofacies and changes in chemostratigraphy and TOC over short distances is important to better evaluate the impact of depositional and diagenetic environments on hydrocarbon generation, completion efficiency and productivity in the Marcellus and other shale gas reservoirs.

AAPG Datapages/Search and Discovery Article #90373 © 2019 AAPG Eastern Section Meeting, Energy from the Heartland, Columbus, Ohio, October 12-16, 2019