 Situated near the South Pole at the start of the Ordovician, the region was likely barren and nearly lifeless.The Austroalpine and South Alpine superunits formed a shelf that received clay and sand sediments from the continental interior.The Ordovician also marked a poorly understood period of igneous activity, that resulted in granites and the Blasseneck Porphyroid, a weakly metamorphosed porphyry in the Greywacke Zone, with mixed layers of pyroclastic flow and lava.