| Ann and her husband
are geologists who work on a number of different projects. She explained
why there was gold in them there hills.
'The rock formation of the area
is all metamorphic, it has been sedimentary rock that has been heated
and put under tremendous pressure to form what is known as the Klondike
Schist. There is no way of knowing what kind of rock made up the original
sediment of the rock. Gold is initially injected into cracks in the
rocks with other minerals such as quartz. Over time the gold has been
washed away from the veins and into streams and river beds. Over time
these river beds have been covered with sediment from the rivers, fine
gravels and vegetation which has rotted and turned into soil and redirected
the streams and rivers. The gold that miners extract today sits on the
bottom of ancient creeks and river beds. As gold is heavier than other
metals it sunk to the bottom and has stayed there. Because no glaciation
occurred in the area the soil, vegetation and sediment that sits on
top of the old stream beds has not been removed and has kept the gold
in place for thousands of years. Initially it was thought that gold
would only be found on the valley floor of the Klondike's tributary
creeks but because the gold is part of ancient streams and rivers it
has been found higher up on the benches. The gold here is known as 'alluvial',
here it is called 'placer' as it is already released from its original
source.
Peter (Ledwidge) is currently
working with a number of people conducting hard rock exploration looking
for what is called the 'Mother Lode', which is the original rocks where
it is believed the gold in the creeks has come from. Gold is pretty
hard to detect because it is such a stable material it does not link
to any other materials, so you can test the water and find trace elements.
Sure it is often found with quartz, which makes up the white gravel
associated with the pay dirt but it is really hard to detect in any
predictable systematic way which is why the mother lode has not yet
been found. The signs are good that it is out there though.'
Ann also works on mining applications
to show the water board where the water source for the mine is coming
from and where it will be returned to.
'There have been a lot of changes
to regulations on mining. Until 96 you could do pretty much anything
with your land but now there has to be reclamation to restore the land
to how it was before. The mines have seen a greater increase in wildlife,
since the creeks where the permafrost has been melted offers new richer
areas. Creeks that have been mined re-create a better landscape for
wildlife such as moose, water fowl and fish such as grayling. There
are also strict regulations on water sediment being returned to the
creeks. There can only be 5 ml of sediment in every 100 ml of water
being returned to the creeks after it has been used for mining.'
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interviews with
Mr Smith UK David McBurney
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