Characteristics, Petrogenesis and Resource Significance of the Limestone with Polygonal Reticulate Structure of Pagoda Formation, in Northwestern Hunan Province
Huang Leqing
Liu Wei
Bai Daoyuan
Li Zehong
Liang Enyun
Chen Zhenbao
Abstract：The limestone of the upper Ordovician Baota Formation in northwestern Hunan has a crack structure, bearing the characteristics of"decreasing cracks from top-bottom, no crossing between adjacent layers, multi-period deformation, waterlike filling"in rock sequence, which is a special sedimentary structure in geological period.In order to find out its genetic mechanism and its internal relationship with the evolution of the Yangtze basin, the author does research from aspects including lithology, fracture characteristics, geochemical characteristics, basin model and comprehensive comparison of the known causes of crack-like polygonal reticulate structure.It is found that the crack structure is a kind of initial slit formed under the influence pen contemporaneous gel condensation.Then under the control of tectonic extrusion, the basin sinks rapidly, a fluid environment in an abnormal high pressure filed is formed in the basin, which leads to squeezing, filling and initial cracks reconstruction from the plaster material in underlying water-rich rocks.This study on the crack structure of the Baota Formation provides petrological data for the study on the mechanism of tectonic-fluid-rock interaction.Meanwhile, agood dredging function of the cracks has an important practical significance for the study on mineralization as well as oil and gas accumulation.
Keywords：polygonal reticulate structureBaota Formationformation mechanismOrdovicianNorthwestern Hunan Provincerock
Publication Date：2019-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：16( 399-414 )