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The lack of available thermochronological methods has so far hampered reconstructions of the cooling and exhumation histories in carbonate rock regions. Here we develop a new trapped charge thermochronometry tool based on the thermoluminescence signal of dolomite. It has a closure temperature range of 45–75 °C and is applicable to carbonate domains with cooling rates of 2–200 °C per million years. This new thermochronometric technique is tested in the central Apennines, where seismogenic, carbonate-hosted normal faulting controls regional neotectonics. Thermoluminescence dating is applied along the northeastern shoulder of the Late Pliocene-Quaternary L’Aquila Intermontane Basin, at the footwall of the extensional Monte Marine Fault. Dolomite samples from the bedrock have a mean thermoluminescence age of 4.60 ± 0.35 millions of years, whereas dolomite clasts within the fault damage zone have a mean thermoluminescence age of 2.53 ± 0.13 millions of years. These new thermoluminescence ages, corroborated by the existing stratigraphic constraints, (i) provide the first direct, low-temperature exhumation ages of the carbonate bedrocks in the central Apennines; (ii) constrain the activity of the basin boundary faults along the northeastern shoulder of the L’Aquila Intermontane Basin. Our study demonstrates the potential of dolomite luminescence thermochronometry in reconstructing the low-temperature cooling/exhumation history of carbonate bedrocks.
Dolomite thermochronometry based on thermoluminescence signals can reconstruct the cooling and exhumation histories of carbonate rocks undergoing slow exhumation, with cooling rates in between 2 to 200 Celsius degrees per million years, as shown by a study constraining the low-temperature exhumation ages of carbonate rocks in the central Apennines.