ABSTRACT The historic town of New Harmony is located along the Wabash River in Posey County, Indiana, and served as a focal point for natural scientists, especially geologists, in the early nineteenth century. Notable geologists that lived and worked in New Harmony during this time include Edward Travers Cox, William Maclure, Fielding Bradford Meek, Joseph Granville Norwood, David Dale Owen, Richard Dale Owen, Benjamin Franklin Shumard, Gerard Troost, and Amos Henry Worthen. Other natural scientists who worked in New Harmony include Charles Alexandre Lesueur and Thomas Say, and the town was also visited by James Hall, Leo Lesquereux, Sir Charles Lyell, and Alexander Philipp Maximilian, Prince of Wied. The purpose of this field-trip guide is to highlight the scientific and geologic enterprise that operated in nineteenth-century New Harmony, Indiana. There will be a tour of historic buildings including laboratories used by David Dale Owen, such as the Rapp-Owen Granary and his fourth laboratory, which was constructed in 1859. Furthermore, field-trip participants will visit a new geology exhibit at the Working Men’s Institute, an organization established by William Maclure in 1838. The field excursion will also visit historically significant localities, including Mississippian and Pennsylvanian exposures, the type section of the West Franklin Limestone, and a Pennsylvanian paleobotanical site that yielded extensive collections of plant fossils in the mid-nineteenth century. Finally, this field trip will provide an opportunity to discuss the importance of art to geological studies in the early nineteenth century. Specifically, hand-colored geologic maps, cross sections, and renderings of fossils were included with many of the scientific reports of historic New Harmony, and are reflected by the superb artwork of Charles Alexandre Lesueur, David Dale Owen, and Thomas Say. Access to view their original scientific artwork is possible only through special arrangement with the Working Men’s Institute.

Abstract: While coalbed methane (CBM) is a significant source of natural gas production globally, uncertainties regarding the proportions of biogenic and thermogenic natural gas in CBM reservoirs still remain. We integrate major gases, hydrocarbon composition, hydrocarbon stable isotopes and noble gases in fluids from 20 producing CBM wells to more accurately constrain the genetic source of natural gases in the eastern Illinois Basin, USA. Previous studies have indicated primarily biogenic production of methane (>99.6%) with negligible contributions from thermogenic natural gases. However, by integrating noble gases, we identify quantifiable (up to 19.2%) contributions of exogenous thermogenic gas in produced gases from the Seelyville and Springfield coal seams. Thermogenic gases are distinguished by a positive relationship between methane, ethane and helium-4, lower C 1 /C 2 +, heavier δ 13 C-CH 4 , more radiogenic noble gases ( 4 He, 21 Ne*, 40 Ar*), and lower abundances of atmospherically derived gases ( 20 Ne, 36 Ar). Biogenic gases displayed lighter δ 13 C-CH 4 , higher C 1 /C 2 +, higher levels of atmospheric gases and lower abundances of radiogenic noble gases. Our data suggest that natural gases from a deeper, exogenous thermogenic source likely migrated to the Pennsylvanian-aged coals at an unknown time and later mixed with biogenic methane diluting the geochemical signature of the thermogenic methane within the Springfield and Seelyville coal seams.