UNGI CIMMM Domestic Unconventional Resource Consortium
UNGI CIMMM is a Consortium that has been initiated in February 2012 and funded by several major and independent oil companies, global service companies, NETL, several DOE National Laboratories for collaborative fundamental research in shale gas and shale oil reservoir characterization and operations. CIMMM is a product of 20 integrated multidisciplinary, multiscale projects to investigate US Shale basins (Eagle Ford, Bakken, Niobrara, Marcellus, Utica, Barnett, Green River and Mancos) to study their similarities and differences from each other as well as from the conventional reservoirs in the US and abroad. Both experimental and theoretical modeling studies are being conducted to produce the deliverables using coupled geomechanics and fluid flow measurements and simulations. The initial research phase is for three years that are continued with concentrated In Situ Shale Reservoir Laboratory Design, Built and Operations for continued fundamental and operational research for foreseeable future to contribute solution of many challenges are presently faced by the industry in economically viable and environmentally friendly production from shale gas, tight oil and organic rich tight reservoirs.
Brief description of projects in the consortium is provided in the following paragraphs.
• Geological, Geochemical and Petrophysical Characterization of Organically Rich Shale Basin(s). The first project (A1) in UNGI CIMMM Consortium is led by Dr. Azra Tutuncu and Dr. Steve Sonnenberg. The project involves conducting experimental and modeling research investigating Eagle Ford Shale Basin to capture the impact of TOC, thermal maturity, natural fracture density, geochemical and mineralogical content of the source rock and adsorbed gas on brittle/ductile transition of shale and its connection to permeability and porosity of the formation and its productivity and brittleness.
• Coupled Geomechanics, Acoustic, Transport Property Measurements and Modeling for Enhanced In Situ Reservoir Characterization. This is a project in UNGI CIMMM Consortium (A2) that involves measurement and modeling study for Eagle Ford, Bakken and other shale plays to fundamentally understand the shale characteristics for more efficient, economically viable and environmentally safe drilling, production and fracturing in unconventional reservoirs. The project is led by Dr. Azra Tutuncu. Simultaneous coupled measurements of acoustic, mechanical, petrophysical property and strength anisotropy under elevated pore pressure are conducted. An unconventional shale, tight gas sand and carbonate database is being created along with modeling of multidisciplinary coupled integrated measurements for realistic coupled behavior of the unconventional reservoirs and their seal overburden and underburden rocks. Triaxial and true triaxial coupled measurements of multidirection deformation, failure, ultrasonic velocities and attenuation, permeability and resistivity are conducted at elevated pore pressure and temperature on single cylindrical sample simultaneously. Imaging capability under elevated pressure conditions with CT-Scanning for realtime monitoring of deformation and fracturing is also the unique true triaxial measurement capability implemented at UNGI Projects.
• A Study of Permeability and Porosity of Shales by Using NMR (A3) The project includes measurement and modeling of shale porosity, diffusion and permeability in nano-scale using 400 MHz high field NMR as well as conventional 2 MHz Nuclear Magnetic Resonance tools at UNGI. This project is led by Dr. Yuan Yang and Dr. Azra N. Tutuncu. Currently shale NMR data including dispersion data are collected at various frequencies to incorporate geological and geomechanical 3-D modeling of Eagle Ford and other shale formations for fundamental nanoscale understanding of pore connectivity and structure in organic-rich shale formations and to understand their difference from seal shales and other reservoir rocks.
• Experimental Investigations of Improved Oil Recovery in Fractured Gas Shale Reservoirs Using CO2 Injection (A5). The project aims investigating gas recovery in fractured gas shale reservoirs for immiscible flooding (CO2 injection) conducted by Dr. Azra N. Tutuncu in PE Department. The project incorporates experimental and numerical analysis of CO2 injection into a gas shale reservoir.
• Applications of Distributed Temperature Sensing (DTS) in Unconventional Well Construction, Stimulation, and Production (B3). This is a research study for investigation of the potential benefits of DTS in unconventional wells for fracture characterization using near-wellbore modeling utilizing commercially available software and field data. The project is lead by Dr. Azra N. Tutuncu.
• Coupled Fluid Flow and Geomechanics Modeling in Fractured Reservoirs with Condensate Saturation (C2). This project is led by Dr. Hossein Kazemi and dr. Azra N. Tutuncu to utilize field data from Bakken, Niobrara, Eagle Ford and Barnett shale formations in conducting experiments and developing relevant computational tools on such abundant, nano- and micro-scale hydrocarbon-bearing resources providing ways to energize or facilitate flow from the pores into the wellbore using suitable EOR fluids and a set of measured PVT data is used to study the phase behavior of the fluids in reservoir conditions.
• Effect of Fractured Medium Characterization on Modeling Flow in Tight Unconventional Plays (C3). This project focuses on the characterization of multi-scale fractures in unconventional plays of interest to the sponsors. Stress-dependent fracture-permeability measurements on core samples are used to develop correlations. The project is led by Dr. Azra N. Tutuncu and Dr. Erdal Ozkan jointly to introduce a research model for a fractured horizontal well producing from a tight, naturally fractured shale play using detailed characterization data. The objective of the model is to delineate the essential features of naturally fractured, nano-pore medium required for accurate predictions of well performances.
• Minimizing Water and Chemical Use in Hydraulic Fracturing Fluid Utilizing Fundamental Geomechanics Principals for More Environmentally Friendly Fracturing (D3). We are continuing this project that verified in Phase I using our one of a kind custom built coupled experimental system how to utilizing the reduction/increase in pore pressure with chemical composition of the injection fluids in fracturing for controlling the effective stress with the use of correct type and concentration of salt only to minimize the amount of water used in fracturing operations for hydraulic fracture effectiveness in shale reservoirs and also how to completely eliminate all other chemicals including friction reducers, guar gum, acids, petroleum distillates, corrosion reducers, scale preventing chemical and radioactive tracers from the modern-day environmentally friendly fracturing fluids and what is the impact on the formation mechanical, acoustic and petrophysical properties and formation failure characteristics alteration. The project is led by Dr. Azra N. Tutuncu. New experimental set-up for Pore Presure Transition Tests allows injecting filed fluids to investigate the role of fluid composition on pore pressure built-up and associated anisotropic mechanical, acoustic and permeability characteristics of the shale formations under true in situ stress and elevated pore pressure conditions.
The project has also been evolved in using the same experiments and modeling into Enhanced Oil Recovery for Reservoir Engineering applications such as Low Salinity Water Injection in shale reservoirs. In-house models has been developed to incorporate rock-fluid interactions during hydraulic fracturing and beyond in order to improve oil recovery as well as increase the efficiency of Stimulated Reservoir Volume through hydraulic fractring with minimum environmental impact.
• Experimental Study of Liquid Nitrogen Fracturing for Unconventional Resource Development (D4). Most formations are water-sensitive to injected water that can cause significant formation damage; in areas where water resource is already strained, the supply of water is also an issue. The use of liquid nitrogen as a fracturing fluid has been studied in this research project. Compared to water, the benefit is multi-fold. First, experiments show that with the thermal effects, liquid nitrogen can initiate the fractures at a lower pressure. Liquid nitrogen evaporates as the formation temperature is restored, leaving no formation damage behind. Compared to other gases such as CO2 or propane, liquid nitrogen can be made much more easily from air, ensuring that there is always sufficient supplies. Liquid nitrogen fracturing tests using shale cores are conducted in this project. The aim is to determine the mechanisms of fracture initiation; to understand the liquid nitrogen carrying capacity of the proppants used; to investigate the strength of materials at low temperatures for planning field-scale experiments and applications. The sustainability of these operations and environmental aspects as a result of the thermal fractures introduced on the operational safety, aquifer contamination and other potential hazards are investigated for risk assessment. The project is co-lead by Dr. Yu-Shu Wu and Dr. Azra N. Tutuncu.
• A Study of Health, Safety, Security, Environment and Social Responsibility (HSSE-SR) Considerations and Challenges for the Development of Unconventional Oil & Gas Plays (F2). This project is led by Dr. Azra N. Tutuncu and Dr. Linda Battalora to perform a comprehensive survey of environmental considerations and challenges for the development of unconventional oil and gas plays and to work with state regulatory agencies in understanding these considerations including but not limited to site development, water safety, water disposal, wastewater treatment, air quality, lease maintenance, surface use, property reclamation, horizontal drilling, and fracturing and the ethical considerations attendant thereto.
• Injection Induced Seismicity (F3). This is a project for investigation and prediction of induced seismicity due to injection operations (waste disposal and hydraulic fracturing) for safe design and execution of unconventional Oil & Gas developments in various plays. The project is led by Dr. Azra N. Tutuncu to perform environmentally sensitive and safe developments of unconventional oil and gas plays and to work with state regulatory agencies in design and execution of proper waste disposal and hydraulic fracturing operations.
• Energy Positive Treatment of Hydraulic Fracturing Flowback (F4). Hydraulic fracturing flowback water contains high concentrations of organic carbon primarily from the gelling agents (e.g., guar gum) added to the fracturing fluid. Approximately 10 to 30% of the gelling agent is recovered in the flowback water. Reuse of the water requires the removal of the residual gelling agent. Chemical oxidation or aerobic biodegradation of the gelling agents requires the addition of high concentrations of chemical reagents or oxygen addition through energy intensive aeration. In contrast, anaerobic degradation can generate methane from the organic carbon contained in flowback and is a net energy positive treatment process. In this research project, we demonstrate anaerobic treatment and methane production of the major organic carbon constituent of flowback water. A two-stage bench-scale anaerobic reactor system are fed synthetic flowback water and this procedure is modeled to demonstrate the two-stage anaerobic process concept. The project is co-lead by Dr. Linda Figueroa, Dr. Azra N. Tutuncu and Dr. Junka Munakata Marr.