Chockstone Forum

      Sponsored By
      ROCK
   HARDWARE

Chockstone Photography

Australian Landscape Prints

Chockstone Forum - Crag & Route Beta

Crag & Route Beta

Area	Location	Sub Location	Crag	Links
All TAS	(General)	(General)	(General)

Topic Date User

New Grade 32 at Fingal - video 18-Jun-2012 At 7:09:56 PM tastybigmac

Message

There be GOLD in them there hills!

GEOLOGY
Rocks of the Mathinna Group of probable Silurian age outcrop
on the hills and in the creek beds, with later gravels and soils
forming the flats used for pastoral and agricultural purposes. The
Mathinna rocks are slates and Quartzites, with the bedding often
masked by the cleavage. The bedding has a strike averaging 3160
with a dip of 80 0 E; the cleavage averages 330 0 with dips from 80 0W
to vertical, and occasionally to the east.
Quartz veins are common in the area, varying from a fraction
of an inch to several feet across. Many of the narrow veins follow
joint planes in the Mathinna rocks. The larger veins, some of which
carry gold in commercial Quantities, cut across both bedding and
cleavage. The strike and dip of the auriferous Quartz veins show
considerable variation. The veins mined at West Miami, Miami
and Great Fingal have a strike to the west or north-west, whereas
the veins at Daylight mine strike north-east. Dips are almost
invariably steep.

How was the dolerite emplaced in that part of Tasmania? Sills between bedding planes? Some other fracturing? And is the Mathinna Group part of the same sediments that make up Eastern Victoria?