Tuesday 22 April 2014

John Hardcastle of Timaru

John Hardcastle; aged about 60, or early sixties(above)
A Brad Pillans map of the South Island showing the location of Timaru. Note the basalt volcanics at Timaru- and nowhere else in the South Island


Saturday 19 April 2014

Depressions in Loess Ground; on the Titel Plateau, and at Timaru in South Canterbury NZ

Christian Zeeden, Michael Hark, Ulrich Hambach, Slobodan B. Markovic, Ludwig Zoeller  2007
Depressions on the Titel Loess Plateau: Form-Pattern-Genesis.  Geographica Pannonica 11, 4-8.

These depressions are fairly shallow, maybe up to 4m in depth; perhaps 50, 100, 200m wide- shallow bowl-like depressions on/in the loess ground surface. Investigated by Zeeden et al- who hint at formation aided by some dissolution processes. One wonders if there might be selective and localised hydrocollapse going on. The Titel depressions have a preferred northwest-southeast orientation which obviously could be significant. To investigate loess hollows more examples are required.. and the ancient literature may have revealed one. John Hardcastle, discussing the Timaru loess in his 'Notes on the Geology of South Canterbury'(1908) mentions some depressions which sound remarkably like the Titel depressions. He gives few details but hopefully some investigations can be launched. There does not appear to be any obvious reason why the Titel and Timaru loess deposits should not be very similar.