Progressive development of stylolites in cryptocrystalline quartz

Author(s)
Zhaoliang Hou, Kun Feng Qiu, Anna Rogowitz, Richard A. Schultz, Hao Cheng Yu, Bernhard Grasemann
Abstract

Stylolites are common dissolution structures in carbonate rocks in the upper crust and document a coupled physical-chemical feedback during pressure solution in rocks. By applying high-resolution electron-based analysis we investigate a rare example of stylolites in cryptocrystalline quartz (novaculite) from western Sichuan Basin, China. The investigated stylolites exhibit an increased amplitude from the tip toward the center, which correlates with the maturity of stylolites and thus provides an excellent opportunity to infer the dynamic processes operating during stylolite formation. Microstructurally, stylolites are characterized by a concentration of biotite and hematite, dissolving irregular quartz grains, and the occurrence of dissolution porosity. By investigating the progressive co-variations between stylolite amplitude and microstructure characteristics from the stylolite tip toward the center, we demonstrate, for the first time, the evidence of stylolite growth through anticracks. It is inferred that stylolites in cryptocrystalline quartz originate from the propagation of mode I micro-cracks around pre-existing biotite, followed by pore-scale dissolution. Both processes, micro-cracking and dissolution, are interacting and co-evolving via a self-organization fashion during shortening. Our study contributes to the ongoing debate about whether stylolites are conduits or barriers for fluid flow.

Organisation(s)
Department of Geology
External organisation(s)
China University of Geosciences, Karl-Franzens-Universität Graz, Orion Geomechanics LLC
Journal
Bulletin of the Geological Society of America
Volume
136
Pages
4417-4432
No. of pages
16
ISSN
0016-7606
DOI
https://doi.org/10.1130/B37461.1
Publication date
11-2024
Peer reviewed
Yes
Austrian Fields of Science 2012
105124 Tectonics
ASJC Scopus subject areas
Geology
Portal url
https://ucrisportal.univie.ac.at/en/publications/ea5db9c7-dc35-4928-8af7-a13d2d2b59c5