F.C. DEEMER REPOSITORY: CHEMOSTRATIGRAPHIC CHARACTERIZATION OF THE BAKER RUN RESERVE NO. 8 WELL IN CLEARFIELD COUNTY, PENNSYLVANIA, USA

The National Energy Technology Laboratory houses the F.C. Deemer Repository, a collection of cutting from 24 wells in north-central Pennsylvania drilled between 1924 and 1958 (Mackey et al., 2019). Combined, the samples cover over 40,000 feet of strata from the Genesee Formation to the top of the Helderberg Group. These samples can provide insight into the depositional environment of two prominent Pennsylvania deep gas fields with the potential for carbon storage, as well as a potential source for critical minerals and rare earth minerals. Using a subset of these samples we developed a workflow for data collection and analysis to characterize the Baker Run Reserve No. 8 (BRR8) well, which is presented here.

The BRR8 well was drilled in July of 1958 on Pennsylvania State Game Land Tract 331 (formerly Tract 93), targeting gas production from the Oriskany in the Rockton deep gas pool. We characterized the cuttings from the collection using descriptions, high-resolution photos, geochemical analysis using two handheld X-ray fluorescence (XRF) analyzers, an Olympus Delta and an Olympus Vanta, and a benchtop PANalytical Axios-Max XRF analyzer of 30 samples to calibrate the handheld XRF measurements.

A hierarchical clustering of the XRF data was performed and revealed four primary facies: sandstone, limestone, shale, and black shale. Four shale subfacies were identified due to various elemental enrichments, listed in parenthesis: anoxic/euxinic shale (Mo, U, V, Ni); carbonate-rich shale (Ca, Mg, Sr); oxic shale (Mn); and dysoxic shale (Fe, Co, Cr). Critical mineral/rare earth elements were observed to be more abundant in two facies, the sandstone in the Nedrow and Edgecliff members of the Onondaga and in shale that transitioned redox state (dysoxic to anoxic; or euxinic to dysoxic). These enriched zones with Y, Pr, La, and Nd co-occur with local enrichments of Ba, Ni, V, and Mo in shale and carbonate facies, and with P in sandstone facies. Future studies will characterize the remaining wells within the Rockton Deep Gas pool building out the depositional setting and providing further insight for resources utilization in the field.

Mackey, P. et al. F.C. Deemer Repository of Drill Cuttings from North Central Pennsylvania; NETL-TRS-2-2019 DOI: 10.18141/1502351.