title: Deformation-resembling microstructure created by fluid-mediated dissolution-precipitation reactions.
abstract: Deformation microstructures are widely used for reconstructing tectono-metamorphic events recorded in rocks. In crustal settings deformation is often accompanied and/or succeeded by fluid infiltration and dissolution-precipitation reactions. However, the microstructural consequences of dissolution-precipitation in minerals have not been investigated experimentally. Here we conducted experiments where KBr crystals were reacted with a saturated KCl-H2O fluid. The results show that reaction products, formed in the absence of deformation, inherit the general crystallographic orientation from their parents, but also display a development of new microstructures that are typical in deformed minerals, such as apparent bending of crystal lattices and new subgrain domains, separated by low-angle and, in some cases, high-angle boundaries. Our work suggests that fluid-mediated dissolution-precipitation reactions can lead to a development of potentially misleading microstructures. We propose a set of criteria that may help in distinguishing such microstructures from the ones that are created by crystal-plastic deformation.
authors.affiliation: ARC Centre of Excellence for Core to Crust Fluid Systems/GEMOC, Department of Earth and Planetary Sciences, Macquarie University, Sydney, New South Wales 2109, Australia.
authors.forename: Liene
authors.initials: L
authors.lastname: Spruzeniece
authors.affiliation: ARC Centre of Excellence for Core to Crust Fluid Systems/GEMOC, Department of Earth and Planetary Sciences, Macquarie University, Sydney, New South Wales 2109, Australia.
authors.forename: Sandra
authors.identifier: 0000-0001-7723-8170
authors.initials: S
authors.lastname: Piazolo
authors.affiliation: Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirawee DC, New South Wales 2232, Australia.
authors.forename: Helen E
authors.initials: HE
authors.lastname: Maynard-Casely