TITLE:
Coal Deformation, Metamorphism and Tectonic Environment in Xinhua, Hunan
AUTHORS:
Huantong Li, Xiaoyan Zou, Jiafeng Mo, Yifan Wang, Fei Chen
KEYWORDS:
Coal Deformation and Metamorphism, Tectonic Environment, Aphanitic Graphite, Structural Properties, Xinhua Hunan
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.6 No.9,
September
25,
2018
ABSTRACT: This article discusses in detail chemical composition, molecular structure,
microstructure phenomena, estimate of the palaeo-stress, paleo-temperature
and the strain rate to deepen the knowledge for the correlation of coal deformation
and metamorphism with structural environment in Xinhua Hunan by
coal quality analysis, XRD and SEM methods, which provide dependable
theoretical foundation for coal resource exploitation and utilization. The results
show that 1) d002 value of six coal samples is from 3.36 to 3.39 nm, coal
resolved itself into aphanitic graphite with the increase of coal rank during
coalification, which is characterized by graphite flakes, and the crystallite size
is from 50 nm to 250 nm; A certain degree of 3R-structure content is increases
and the crystallite size is extend with the coalification process, but
RH-structure content is decreased; 2) the tectonic environment of research
area belongs to the ductile-brittle deformation, which was characterized by
low temperature, low stress, high strain rate; 3) Tianlongshan magmatic intrusion
provided heat source, its side-extrusion made the molecules structure
of coal ordering, distance between layers decreased, finally it caused the formation
of aphanitic graphite.