THE ASHFORD LIMESTONE CAVES
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| From the Ashford Tourism website |
The Ashford limestone caves are located about 20km
north-west of the town of Ashford, between Inverell and the Queensland border.
What was once a crown reserve (set apart in 1915) is now part of the Kwiambal National Park (pronounced
Kiamble), best known for the spectacular MacIntyre
Falls, near which is a delightful camping area at Lemon Tree Flat. Picnic
and toilet facilities are also provided at the caves.
 These caves are not in the same league as the well-known show caves at Jenolan, Wombeyan and Yarrangobilly, in fact there are very few speleothems (decorations) to be found. What you will find is bats, guano (bat droppings) and a sense of adventure as you explore the unknown (to you) cave system. If you would like to read a fascinating account of “An Excursion to the Severn River and the Wallangra Caves” dating from 1892 (here) you will appreciate that some things have not changed, but others have considerably. The most notable change has been the removal of thousands of tonnes of phosphorus-rich guano for use as fertiliser, a process that was underway long before the reserve was established and continued as late as 1967. |
There is a lot of information available about the geology,
history and biology of Ashford Caves. I have given a list of downloadable
resources at the end of the blog.
The caves have been formed in a bed of Lower Carboniferous limestone (probably, though estimates range
from Devonian to Permian), which has been considerably deformed and largely
converted to marble. It contains marine
fossils (mainly crinoid and coral fragments), but remember that this is a
National Park (no collecting allowed) and beyond the fences is private
property, which limits the collecting possibilities to road reserves outside
the Park. As the limestone has been traced for more than 10 km there must be
some accessible outcrops, since the road basically follows the strike of the
limestone. If you locate specimens of interest, tell us about it by adding a comment
below.
There are a few typical karst
features, notably the dolines where caves below have collapsed. You
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| Calcite formations 1999 (my photo) |
might
also come across solution grooves, widened joints and potholes as you walk
around the limestone hill.
Early references note the existence of two main caves. The
removal of so much guano has lowered the cave floors considerably and the two
caves are now joined, making a through trip possible. There are a few other small
caves but none appear to have much potential for new discoveries.
Three species of bat
frequent the caves: Miniopteris
schreibersii (the eastern bent-wing bat), Rhinophilus megaphyllus (the eastern horseshoe bat) and Eptesicus pumilus. Most of those you
will see are bent-wing bats. Do not disturb them by making loud noises or
shining lights on them. During the summer breading season, do not enter the
main cave at all.
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| Bats 1999 (my photo) |
The guano had accumulated to a depth of several metres in
the most favourable places. A typical chemical analysis reveals that it
contains 5-10% of phosphorus. Especially during the Second World War, when
supplies of phosphate from Nauru and Ocean Island were cut off by the Japanese
(both islands were occupied by them) alternative supplies were identified all
over Australia. Ashford Caves was one of these.
Some useful
references.
The Ashford Tourism
site (here); (missing: you will have to search for it)
Guide to NSW Karst and
Caves pp 10-11 (here); (missing. Try DIGS website or search Trove)
DIGS website (needed for the listings below) here. (missing - please let us know if you find it)
Annual Reports of the
Department of Mines, New South Wales, for the period 1939-1945 (DIGS
reference R00001425). This includes
cave maps and guano analyses (beginning on page 82).
The Limestone Deposits
of New South Wales (DIGS R00050689).
An excellent report from 1919 giving information about all the then known limestone
deposits.
The Limestone
Deposits of NSW (1986) Lishmund, Dawood and Langley (DIGS R00056921). A modern,
revised version of the above.
Geological Age of the Ashford Caves Limestone (DIGS R00019198). Report by Raggatt and
Booker, 1940.
A Report on a Visit to the Ashford Cave,
Northern NSW (DIGS R00023521).
1973 Anonymous.
https://johnsbluemountainsblog.blogspot.com/2013/12/links-to-all-blog-entries-and-relevant.html All Blue Mountains blogs and videos
All New England and other Geology blogs and videos
Limestone Caves of NSW
Song Studies. Bible studies based on hymns and songs
Shoalhaven District Geology.
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