Grain shape and mineralogy of loess on New Zealands South Island

Infilled fissures are described from the interface between two loess deposits on Banks Peninsula, South Island, New Zealand. Both loesses differ from the other loesses by having a solifluction deposit at their base consisting of angular basalt fragments of the same angularity as fresh frost shattere...

Full description

Bibliographic Details
Main Author: Harris, Stuart A
Format: Dataset
Language:English
Published: PANGAEA 1983
Subjects:
HAND
Sampling by hand
TeOka
Te Oka Stream
Banks Peninsula
New Zealand
Ice
permafrost
Polarforschung
wedge*
Online Access:https://doi.pangaea.de/10.1594/PANGAEA.753942
https://doi.org/10.1594/PANGAEA.753942
Description
Summary:Infilled fissures are described from the interface between two loess deposits on Banks Peninsula, South Island, New Zealand. Both loesses differ from the other loesses by having a solifluction deposit at their base consisting of angular basalt fragments of the same angularity as fresh frost shattered basalt mixed with the loess. Typically, the fissures are narrow and up to 160 cm deep while the infilling of the overlying loess shows no obvious structure. They occur mainly at higher elevations on south (poleward) facing slopes, and the host loess forms a fragipan of high density. They are most readily explained as being seasonal frost fissures or more probably ice-wedge casts, which would have required either permafrost or deep seasonal frost for their formation. If permafrost had existed, this would imply a cooling of the mean annual temperatures by at least 16 to 18°C.

Similar Items