The Role of Calcite Dissolution and Halite Thermal Expansion as Secondary Salt Weathering Mechanisms of Calcite-Bearing Rocks in Marine Environments Martínez Martínez, Javier Arizzi, Anna Benavente, David Halite Marble Limestone Linear thermal expansion coefficient Climatic cabinet Experimental tests in the cabinet carried out at the University of Oxford were financially supported by the European Commission under the Marie Curie program (FP7-PEOPLE-2012-IEF call, research project "NaturaLime"). This research has been supported by the Spanish Government (MICINN) (PID2020-116896RB-C21 and PID2020-116896RB-C22). This research focuses on the analysis of the influence of two secondary salt weathering processes on the durability of rocks exposed to marine environments: chemical dissolution of rock forming minerals and differential thermal expansion between halite and the hosting rock. These processes are scarcely treated in research compared to salt crystallisation. The methodology followed in this paper includes both in situ rock weathering monitoring and laboratory simulations. Four different calcite-bearing rocks (a marble, a microcrystalline limestone and two different calcarenites) were exposed during a year to a marine semiarid environment. Exposed samples show grain detachment, crystal edge corrosion, halite efflorescences and microfissuring. Crystal edge corrosion was also observed after the laboratory simulation during a brine immersion test. Calcite chemical dissolution causes a negligible porosity increase in all the studied rocks, but a significant modification of their pore size distribution. Laboratory simulations also demonstrate the deterioration of saltsaturated rocks during thermal cycles in climatic cabinet. Sharp differences between the linear thermal expansion of both a pure halite crystal and the different studied rocks justify the registered weight loss during the thermal cycles. The feedback between the chemical dissolution and differential thermal expansion, and the salt crystallisation of halite, contribute actively to the rock decay in marine environments. 2021-10-07T11:56:06Z 2021-10-07T11:56:06Z 2021-08-23 journal article Martínez-Martínez, J.; Arizzi, A.; Benavente, D. The Role of Calcite Dissolution and Halite Thermal Expansion as Secondary Salt Weathering Mechanisms of Calcite-Bearing Rocks in Marine Environments. Minerals 2021, 11, 911. [https://doi.org/10.3390/min11080911] http://hdl.handle.net/10481/70724 10.3390/min11080911 eng info:eu-repo/grantAgreement/EC/FP7/326983 http://creativecommons.org/licenses/by/3.0/es/ open access Atribución 3.0 España MDPI