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The mechanical properties of shale play an important role in hydraulic fracturing design. Although the popular nanoindentation method can be performed to evaluate some mechanical characteristics of organic matter, it is still difficult to fully characterize mechanical properties of organic components of shale due to their small scale which is usually on the order of micrometers or even nanometers. As a novel material characterization tool, Atomic Force Microscopy (AFM) has shown great potential to characterize surface properties and pore structures at micrometer- and nanometer-scale and has been applied to investigate the elastic properties of organic components in shale by multiple researchers. Raman and FTIR can detect chemical bands by utilizing molecular vibration information. Because Raman and FTIR measurements are non-destructive, high sensitivity, and short in duration, they have been used extensively to study maturation processes of organic components in coal and shale samples. To some extent, these two methods can be considered as complementary to each other, and more comprehensive understanding about maturation processes of organic components can be achieved by combining these two methods. In this work, mechanical properties and chemical characteristics of four shale samples with different thermal maturities were investigated. Generally, this study had two objectives: (1) Characterize the mechanical properties of shale samples with different maturity levels through the novel AFM method, and (2) Explore the underlying cause for the change in elastic properties of shale samples from a chemical perspective through the complementary Raman and FTIR methods. The authors would like to express sincere thanks to Enervest Operating, LLC for their support of the ESUP project. Financial assistance for this work was provided by the U.S. Department of Energy through the National Energy Technology Laboratory’s Program under Contract No. DEFE0031576.

The objective for this project is to investigate and characterize the resource potential for multi-play production of emerging unconventional reservoirs in Central Appalachia. The project team includes Virginia Tech; Virginia Center for Coal & Energy Research; Enervest Operating, LCC; Pashin Geoscience, LLC; and Gerald R. Hill, PhD, Inc. The anticipated duration of the project is April 1, 2018 - March 31, 2023. Financial assistance for this work was provided by the U.S. Department of Energy through the National Energy Technology 2 Laboratory’s Program under Contract No. DE-FE0031576.

This work proposes a novel and cost-effective approach to determine coalbed methane (CBM) production and composition from individual coal seams in a multi-zone completed CBM well. The novel method uses water to cover individual coal seams in a low pressure CBM well followed by an Echometer fluid level survey to determine the water level. Corresponding gas flow measurements and natural gas chromatography analysis are used to determine gas production and composition from unique zones. A field test using this technology is conducted in Central Appalachia for a multi-zone CBM well containing 18 coal seams. Test results show that the shallow coal seams contribute the majority of the total CBM production in this multi-zone well, and the deeper coal seams contain more heavy hydrocarbons like ethane and propane. Published version