Today James met with McLaren Vale Geology Map co-author Jeff Olliver to do some ground truthing of the McLaren Vale Geology Map. Vineyard owners the Ledson family were kind enough to show us soil pits they have dug in their paddock.
The paddock is directly south west of Manning's Scrub in an area that used to be a market garden at the turn of the 20th century. Later in the sites history the paddock was mined for sand.
The geology under the sand is Pirramimma Sandstone, with seams of Ironstone.
Left - The formation of Ironstone occurs when sand, which has iron leached through it, is bound together and turns into rock (below). Ironstone is widespread source of iron (Fe), although it only contains less than 50 percent iron, far less than the main source of iron that is mined in central Australia hematite.