February Walk- Borenore Caves – Corals, shells and Sea Lilies

February Walk- Borenore Caves – Corals, shells and Sea Lilies

By Jane Munro

Last Sunday, a group of 26 walkers from our club travelled out to the Borenore Karst Conservation Reserve, near Molong, to walk the track along Boree Creek and explore the limestone caves. This is one of several limestone karst areas in the central west. Over 400 million years ago, during the Silurian Period, this area was covered by a shallow sea, surrounding a chain of volcanoes, just off what was then the eastern coastline of our continent.

The walk offered 3 options, but in the end we took only option A (a 9km walk) and option B (7km).

We were delighted to welcome several visitors and one new member. The weather was kind, after the preceding weeks of heatwaves and bushfires. In warm sunny conditions we all set off along the well made track which runs along the northern bank of Boree Creek, enjoying the shade provided by huge old casuarinas (river oaks). This was a new area to the majority of the walkers, so we set out with expectations of discovering new things.

After about a kilometre, the track entered the outcropping limestone, with its sculptural shapes and crevices hinting at the cave structures within, eroded out by the downward seepage of water over thousands of years. This country is very different to the sandstone landscapes we are familiar with in the more easterly areas.

The first cave we came to was the Tunnel Cave, which during winter is home to a threatened species, the hibernating eastern bentwing bats, and closed to the public. In summer however, the bats are not in residence. John and Sharon explored this cave and promised to show the rest of the group on the way back.

The track rose up, crossed over a limestone ridge and led back down to the creek, and our destination, Verandah Cave. We ate our lunch in the cool shade of the long, curving overhang of this cave, through which Boree Creek flows. Interesting cave formations were observed- terraces, stalagmites and stalactites, formed from clayey-limestone mixture which we could see seeping down through the roof.

After lunch, several walkers decided to explore the darker recesses of this cave, following the creek and emerging into the sunlight on the other end. Here there were several limestone boulders with fascinating water-worn shapes. In some of these boulders, and on the cave walls, it was easy to see fossils of the ancient marine creatures who inhabited this warm, shallow sea 420 million years ago. We saw fossil shells, corals/bryozoans and crinoids (“sea lilies”). These marine organisms inhabited the area in the time when the first green plants were just beginning to appear on the earth’s land surfaces.

After lunch we returned the way we had come, to Tunnel Cave. Several walkers explored this cave which turned out to be surprisingly large. This is where the 2 groups parted company, with the Option B group continuing back to the picnic area along Verandah Cave Track. The Option A group set out up the hill on the Livermore Track, in search of the quarry where Borenore Marble was quarried over 100 years ago. Red and blue coloured marbles, full of fossils, were used as building and ornamental stone in some significant buildings including Central Railway Station and Jenolan Caves House. A table made by the well known sculptors Frank and Peter Rusconi in about 1905, is held in the Powerhouse Museum.

The Livermore Track led us up to the highest part of the reserve and we got good views of the surrounding countryside, including Mt Canobolas, one of the extinct volcanoes of the area. The quarry proved to be difficult to find, and when we did find it, it was not what we had expected, being long disused and reclaimed by the bush. We were able to make out traces of the fossils on the rock surfaces, and could see boreholes which had been drilled during the process of extracting the marble, over one hundred years ago.

Arriving back at the picnic area, the Option B walkers told us about the Arch Cave walk, which is quite close to the picnic area, and well worth a visit. It will definitely be on my list for the next trip out that way.

After a brief reunion of the two groups we all headed off to the Sweetness Café in Molong which we were very happy to reach before the closing time of 4.30. I’m not sure what the owners thought when over 20 bushwalkers arrived at 4.20, but I hope they were pleased! All enjoyed excellent gelato and coffee before the journey back to Mudgee. Thanks to everyone for a really interesting and enjoyable day.