The general reconnaissance of the Pilbara Goldfield, commenced
in 1903, was completed at the close of the field season of 1905. On
this occasion the portions of the district not previously visited were
reached by way of Roebourne, and the Pilbara Goldfield entered by
the crossing of the Yule River at Womerina Pool.
Close by Womerina Pool is the site of a small alluvial gold
rush some little time ago. The pool itself lies at the foot of a long
serrated ridge, which forms a gigantic horseshoe of several miles in
length, the southern arm of which returns to the Yule River near
Minnaginienna Pool, some miles to the south of Womerina.
At the latter place the banded quartz which constitutes the
horseshoe range is of considerable thickness and underlies at a very
high angle to the south. At the scene of the alluvial rush near
Womerina, the laminated quartz has been subjected to a con-
siderable amount of disruption (Fig. 51). A well marked fault
trending generally 156 degrees is seen traversing the banded quartz
which forms high cliffs in the vicinity.
A small creek, falling into the Yule River and draining the
valley between two readily identifiable beds, has been the one which
seems to have carried the bulk of the gold. Judging by the con-
dition and situation of the workings, the gold seems to have been
concentrated in the vicinity of the fault which crosses the valley
almost at right angles. The laminated quartz veins are associated
with quartzites, slates, and cleaved greenstones of the type common
to other Pilbara centres.
Up the valley between the arms of the horseshoe, the country
rock is granite which forms part of that occupying such extensive
areas in the district. Where the range is crossed by the track to
the Wodgina Tinfield, the slates and other associated rocks give
place to granite, which sends out veins and dykes into them.
Considering the identity of the geological structure of this
range with other portions of the district in which tin mining has
been carried out, there seem good grounds for advising that atten-
tion should be paid to prospecting the margin of the intrusive
granite in this neighbourhood in the hope of finding tin also.
PIO Price at posting:
1.7¢ Sentiment: Buy Disclosure: Held
