Hydrothermal alteration in anthracite from eastern Pennsylvania: Implications for mechanisms of anthracite formation

The Occurrence and Origin of Remagnetization in the Sedimentary Rocks of North America

“…The migration of “orogenic fluids” into the North American interior has also been inferred from fluid inclusion studies [e.g., Leach and Rowan, 1986; Dorobek, 1989], hydrothermal alteration of coal [Daniels et al, 1990], and potassic alteration [e.g., Hearn and Sutter, 1985; Hay et al, 1988]. Some of the phenomena are synchronous with the timing of orogenesis which, as with Late Paleozoic remagnetizations, suggest they may be linked to fluid migration as a result of tectonic activity.…”

Diagenesis to very low-grade metamorphism in lower Palaeozoic sediments: A case study from deep borehole Tobolka 1, the Barrandian Basin, Czech Republic

“…Alternatively, the elevated optical reflectance values of these particles can be ascribed to the localised influence of hot fluids that have migrated along permeable thrust planes and detachment zones, and could have transported heat from depth, thereby increasing the coalification of affected organic particles (e.g. Daniels et al, 1990;Lünenschloss et al, 1997).…”

Coal Formation and the Origin of Coal Fires

“…Shear stress, frictional heating, and localized fluid flow are considered more probable mechanisms for this vertical rank profile. Daniels et al (1990) collected 15 coal samples from the anthracite fields of Pennsylvania and analyzed minerals from three distinct locations with the coal: in the coal matrix, in the systematic cleat, and in a poorly mineralized nonsystematic joint set. Mineral assemblages in the three were significantly different; the differences are attributed to differences in the composition of fluids during late stage diagenesis.…”