While the Central Appalachian region is known for such hydrocarbon resources as coal, it also hosts unconventional gas resources, such as coalbed methane, shale gas, and other tight gas formations.
Many of these gas resources, at depths of up to 15,000 feet, are vertically stacked so that a single well or group of wells could produce simultaneously from multiple reservoirs. While many of the shallower reservoirs produce at relatively low production rates, the deeper formations, referred to as emerging plays, remain largely untested.
A group of academic and industry experts, including the Virginia Center for Coal and Energy Research (VCCER), EnerVest Operating LLC, and researchers at Virginia Tech believe that these emerging plays offer the potential for increased hydrocarbon resources for the state and nation. Their development could provide a critical economic transformation to a region transitioning from coal mining.
In a collaborative effort, researchers from VCCER and Virginia Tech are leading a field laboratory that will begin drilling a 15,000-foot characterization well to explore and investigate the potential for multiplay production of emerging unconventional reservoirs in Central Appalachia.
The Emerging Stacked Unconventional Plays project is led by Nino Ripepi, an associate professor of mining and minerals engineering in the College of Engineering, and is a continuation of work started in April 2018 with more than $8 million in DOE support. Since the project’s start, Ripepi and the research team from VCCER and Virginia Tech have sited, designed, permitted, and set surface casing on a 15,000-foot characterization well to explore the potential of deep unconventional resources.
The group has positioned a triple stand drilling rig at a field site in Wise County, Virginia, to drill to a planned depth of 15,500 feet.
“This work offers a chance to identify and evaluate the resource potential of multiple reservoirs in the area, which in turn can lead to further natural gas development and job growth in a region of the country hard-hit by the downturn in coal,” Ripepi said.
A primary objective of the project is obtaining data needed to better understand the energy resources and their potential development. Core analysis and reservoir modeling are essential to evaluating the production potential of unconventional gas resources, said Ripepi.
“The analysis of rock cores at VCCER and Virginia Tech laboratories, coupled with information gained from state-of-the-art well logs, will provide inputs for reservoir modeling activities,” Ripepi said. “Modeling can more accurately simulate hydrocarbon production, and the resulting predictive simulations will help researchers develop strategies that can produce hydrocarbons economically from these deep reservoirs.”
Researchers will analyze rock cores acquired from the deep drilling activities in labs on campus by examining permeability, fracture conductivity, and adsorption, and by conducting geochemistry experiments to identify parameters to input into predictive reservoir models.
“While many in our community and world are navigating uncertain times, this research project provides an opportunity to take a step away from that world and study rocks that were created hundreds of millions of years ago,” said Ripepi. “It is exciting to be at the forefront of exploring the geologic unknown in a search for hydrocarbon resources that are critical to the future of the economy and future generations.”