Biomarkers Thermal Maturity Parameters in Bitumen as a Proxy for Seismic vs. Aseismic Mirror-like Fault Surfaces
Abstract
Mirror-like Surfaces (MSs) are ultra-polished fault surfaces that experimental studies have shown can form during seismic and aseismic deformation (slip rates ≈1 m/s vs. <0.0001 m/s). To determine which MSs form during seismic (rapid temperature increase) or aseismic (negligible temperature increase) slip along the fault, we measured sterane and hopane thermal maturity parameters in bituminous MSs and their underlying slip zone. Samples with MSs were taken from faults hosted in bituminous dolostones from the Central Apennines, Italy, with displacements ranging from millimeters to meters. To support interpretation of the naturally formed MSs, thermal maturity was also assessed for experimental MSs obtained at seismic (1 to 3 m/s) and sub-seismic (0.0001 m/s) slip rates, and for powders statically heated at 400 °C for 2 seconds up to 12 hours. Higher thermal maturity in MSs with respect to the associated slip zone were measured in most of the natural MSs and in the “seismic” experimental MSs. For static-heating experiments, heating at less than 30 seconds was sufficient to change concentrations of biomarkers, while heating for more than 60 seconds was needed to increase sterane 20S and hopane 22S thermal maturity parameters. We show that sterane 20S and hopane 22S parameters have different friction- and burial-induced thermal maturation pathways. We conclude that, with respect to “aseismic” MSs, rapid temperature increase during earthquakes can locally alter biomarkers and increase thermal maturity in “seismic” fault Mirror-like Surfaces.
Related
- Quantitative histology for maturity staging : Timing is everything
- Real-time determination of swine manure liquid compost maturity by oxidation-reduction potential and pH monitoring.
- Radiation regimes shape microbial light-harvesting strategies and network organization on glacier surfaces
- Regime-aware retrieval of lower-tropospheric stability and a sensitivity-weighted diagnostic of cross-site transferability over heterogeneous land surfaces
- Flow dependence of boundary-layer scheme parameters revealed by stochastic inversion
BibTeX
@misc{chinello2026biomarkers,
title = {{Biomarkers Thermal Maturity Parameters in Bitumen as a Proxy for Seismic vs. Aseismic Mirror-like Fault Surfaces}},
author = {Miriana Chinello and Andrea Schito and Stephen Alan Bowden and Elena Spagnuolo and Stefano Aretusini and Telemaco Tesei and Giulio Di Toro},
howpublished = {EarthArXiv},
year = {2026},
month = sep,
doi = {10.31223/x5mn6t},
url = {https://eartharxiv.org/repository/view/15055/},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Biomarkers Thermal Maturity Parameters in Bitumen as a Proxy for Seismic vs. Aseismic Mirror-like Fault Surfaces
AU - Miriana Chinello
AU - Andrea Schito
AU - Stephen Alan Bowden
AU - Elena Spagnuolo
AU - Stefano Aretusini
AU - Telemaco Tesei
AU - Giulio Di Toro
PY - 2026
DA - 2026/09/18
PB - EarthArXiv
DO - 10.31223/x5mn6t
UR - https://eartharxiv.org/repository/view/15055/
AB - Mirror-like Surfaces (MSs) are ultra-polished fault surfaces that experimental studies have shown can form during seismic and aseismic deformation (slip rates ≈1 m/s vs. <0.0001 m/s). To determine which MSs form during seismic (rapid temperature increase) or aseismic (negligible temperature increase) slip along the fault, we measured sterane and hopane thermal maturity parameters in bituminous MSs and their underlying slip zone. Samples with MSs were taken from faults hosted in bituminous dolostones from the Central Apennines, Italy, with displacements ranging from millimeters to meters. To support interpretation of the naturally formed MSs, thermal maturity was also assessed for experimental MSs obtained at seismic (1 to 3 m/s) and sub-seismic (0.0001 m/s) slip rates, and for powders statically heated at 400 °C for 2 seconds up to 12 hours. Higher thermal maturity in MSs with respect to the associated slip zone were measured in most of the natural MSs and in the “seismic” experimental MSs. For static-heating experiments, heating at less than 30 seconds was sufficient to change concentrations of biomarkers, while heating for more than 60 seconds was needed to increase sterane 20S and hopane 22S thermal maturity parameters. We show that sterane 20S and hopane 22S parameters have different friction- and burial-induced thermal maturation pathways. We conclude that, with respect to “aseismic” MSs, rapid temperature increase during earthquakes can locally alter biomarkers and increase thermal maturity in “seismic” fault Mirror-like Surfaces.
ER -