40Ar/39Ar age evidence for an impact-generated hydrothermal system in the Devonian Siljan crater, Sweden
Crater-forming events are generally followed by the development of hydrothermal systems due to the rapid heating of the target rock. Such hydrothermal systems are a feature of nearly all large terrestrial impact structures. For the Siljan impact structure in Sweden, there is evidence for such a fossil hydrothermal system, possibly triggered by the impact event ca. 380 Ma. To investigate the therma