The paleoenvironmental significance of trace fossils in Devonian sediments (Taylor Group), Darwin Mountains to the Dry Valleys, southern Victoria

Summary A review of trace fossils in the Taylor Group from the Britannia Range to the MacKay Glacier indicates that they varied significantly both spatially and temporarily within the Devonian basin. New studies in the south provide a better understanding of ichnofaunas in the Junction Sandstone (570m) and Hatherton Sandstone (450m), with new information on very large burrows in the well-dated Aztec Siltstone. The burrow Heimdallia chatwini occurs in dense populations only in the northern part of the basin (Dry Valleys), but are not found above the Heimdall Erosion Surface. This surface is followed by thick horizons of dense Skolithos linearis burrows that indicate a change of environment. The Skolithos zone can be traced into the southern part of the basin (Darwin Glacier region) beyond the extent of the erosion surface. The Skolithos burrows suggest that the Devonian basin was subjected to a widespread marine incursion sometime during the Early to Middle Devonian