Complex sentence: Whether due to lithospheric cooling also known as thermal subsidence or the compressional activity in the area reactivated some extensional faults the extension is marked by the isotopic ages of the previously mentioned rocks.
Split into simpler sentences: Whether due to lithospheric cooling, also known as thermal subsidence, or the compressional activity in the area reactivated some extensional faults. The extension is marked by the isotopic ages of the previously mentioned rocks.