Previous studies demonstrated that melting, initiated by supercritical fluids in the 375–400 °C range, occurred as part of anthracite metamorphism in the Appalachian Basin. Based on the known behavior of vitrinite at high temperatures and, to a lesser extent, at high pressures, it was determined that the duration of the heating, melting, and resolidification event was about 1 h. In the current study, featureless vitrinite within banded maceral assemblages demonstratesthe intimate association of melted and resolidified vitrinite with anthracite-rank macerals. By analogy with metamorphosed inorganic rocks, such associations represent diadysites and embrechites, i.e., cross-cutting and layered migmatites, respectively. Even though the temperature of formation of the anthracite structures is several hundred °C lower than that seen in metamorphosed inorganic rocks, anthracites are metamorphic rocks and the nomenclature for metamorphic rocks may be appropriate for coal.
|State||Published - May 2021|
Bibliographical noteFunding Information:
We acknowledge the late Ralph Gray for donating his collection of Narragansett Basin petrographic photographs (Fig. 1C,D) and the Vanderbilt University Department of Earth and Environmental Sciences (Fig. 1G,H) for donating their coal collection to the University of Kentucky CAER. Blaschak Coal Corp. Mahanoy City, Pennsylvania, supplied the coal samples illustrated in Fig. 1A,B. Blaschak Coal Corp. supplied the Buck Mountain coal sample as part of a subcontract to the University of Kentucky from Lehigh University under their research contract from Ben Franklin Technology Partners of Northeastern Pennsylvania. We thank all of our editors and reviewers for their patience and guidance through the review process.
© 2020 Elsevier B.V.
- Mesozoic basins
- Metamorphic texture
- South Africa
ASJC Scopus subject areas
- Earth and Planetary Sciences (all)