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The thermal influence of a Miocene stratovolcano (Matra Volcano) on its basement was studied by apatite and zircon (U-Th)/He thermochronometry. The pre-Miocene substratum of the volcano contains Mesozoic sedimentary units as well as the nearby exhumed igneous Recsk Complex. The Oligocene emplacement age of the Recsk Complex is constrained by zircon U–Pb geochronology to be 29.6 Ma, which serves as a benchmark for the beginning of its thermal history. All measured apatite (U-Th)/He-ages (19.9–5.9 Ma) and most of the zircon (U-Th)/He-ages (26.2–17.7 Ma) are considerably younger than the emplacement age of the Oligocene Recsk Complex, implying thermal overprint by the adjacent Miocene Matra Volcano. The apatite and zircon He ages of the Oligocene complex increase from S to N, providing clear evidence of a northward weakening thermal overprint. The post-Oligocene thermal history of the basement was reconstructed via one-dimensional subsidence/thermal modelling. According to zircon He modelling, the thickness of the covering units above the Recsk Complex was estimated at 1000–1500 m and the heat flux was around 200 mW/m 2 during the Miocene volcanism. Thermal modelling based on apatite He data suggests that the Miocene volcanism was followed by intensive erosion and the exposure of the Recsk Complex by Late Miocene. Supplementary material: Locality, petrography and age-yield of the dated samples of the Recsk Igneous Complex and details of laser ablation ICP-MS dating of zircons from the Recsk Complex are available at: https://doi.org/10.6084/m9.figshare.c.4127444

The Lahoca and Recsk Deep ore complex was formed in relation with andesite volcanics and diorite porphyry intrusives of Paleogene age. The zone is long known for significant enrichment of Cu, Pb and Zn ores. The presence of gold was recorded in the early years of the Lahoca mine. Epithermal and mesothermal gold enrichments are both known in the ore complex. In the epithermal zone low and high sulfidation varieties were identified on the volcanic level of the complex. In the mesothermal zone, significant gold enrichment was indicated in the porphyry copper and skarn copper, zinc ore zones and Pb-Zn veins. In the high sulfidation and the mesothermal copper skarn ore types a moderate correlation between Au and Cu was recorded.