Muogamarra & Oxford Falls
Muogamarra was first reserved as a private sanctuary in 1934 by John D. Tipper who named it using an Awabakal word meaning ‘to preserve for the future’. In 1969 the sanctuary was combined with the Sir Edward Hallstrom Faunal Reserve to create a 2,274 ha Nature Reserve administered by the National Parks and Wildlife Service (NPWS). As a Nature Reserve it is a reference area managed for education and research, and has only limited public access for school groups or for guided walks over six weeks during Spring. Bookings with NPWS are essential and places fill early (details below).
The Reserve contains more than 900 native plant species in a number of associations, the distribution of which can be partly linked to rock and soil conditions, aspect and fire history. The sandstone slopes carry woodland and low woodland with scribbly gum, bloodwoods, angophora and banksia. The diatremes have been cleared, but originally would have carried tall open forest with Sydney blue gum, cabbage palms, figs and water gums. The crater may have included red cedar, which is still present in Campbells Crater. Many of these trees would have attracted early timber getters who would also have noted the better-quality soil partly derived from the volcanic breccia.
Some 14 mammals, 16 reptiles and greater than 140 bird species have been recorded. Original vegetation in Peats Crater would have been more mesic (requiring increased moisture) than on the sandstone slopes.
Geologically the Reserve provides a full section through the Hawkesbury Sandstone, two Jurassic diatremes (volcanic necks), and part of the largest igneous dyke in Sydney. Some of its Aboriginal history is revealed in rock engravings and small middens, and its European history is seen in C19 roads, building remains, and stories of land use.
Diatremes
By far the most interesting volcanic features in the Sydney Basin are eruptive circular vents filled with volcanic breccia called diatremes. Popularly known as ‘volcanic necks’ or named as ‘craters’ diatremes located in the sandstone country form spectacular landscape features of ampitheatre like valleys eroded below the plateau surface. Peats Crater in Muogamarra, is an excellent example and provides a spectacular view from a lookout on the ridge near the Field Studies Centre. Downstream of the main ‘crater’ through the gorge which follows the line of a dyke there is a second diatreme but the only evidence of it is the valley shape and a very small outcrop of weathered breccia in the creek bed.
Peats Crater Muogamarra Nature Reserve
History
We have little knowledge of the Aboriginal history of Muogamarra which was part of the Country of the Dharug or the Guringai people at the time of European contact. Rock engravings were first noted by Surveyor Govett in 1829 and others were recorded by W.C. Campbell in 1896. We have no knowledge of the significance of any of this work and even our identification of some figures may be wrong. As for age, that can be no more than guesses, but it is noted that some figures recorded in the 1940s appear to be much fainter today than they were then.
The first recorded land grant went to George Peat (1798-1870), the son of a First Fleet convict Charles Peat in January 1836. Oddly this grant takes in Peats Bight diatreme, the gorge, and only part of Peats Crater. Was he mainly interested in timber, more open ground at the creek mouth, or simply wanting to limit access to a potential river crossing, or the larger area of better land? Several huts were built and some sort of a road constructed in the period 1830/40, but Peat’s main residence and ferry wharf was across the Hawkesbury River at Fairview Point.
In 1840 George Sullivan was granted 30 acres in Peats Crater and the Rev Henry Britten took up the remainder. This was about the time when the main access road into the Crater was constructed.
In 1886 Joseph Izzard took up land at the creek mouth and built a guest house which was extended in 1902 or 1904 and used by Alfred Burton. It was later occupied by Ned Higgins but it was burnt down in 1939.
Ownership and land use in the late C19 and up to the 1950s has not been properly researched and there are several conflicting names and dates in most accounts. For some decades, the Crater was used as a dairy farm, and later as grazing for dry cattle, in about 1930 a hedgerow of the exotic tree osage orange, was planted across grazing land in the Crater and remains as a heritage item today.
Peats Ferry Road, an early version of the Pacific Highway was constructed in 1927 by large gangs and for a few months a tent school was operated with 14 children at the stone basin by teacher F.V. Christie.
J.D. Tipper was granted a 200 acre lease for the sanctuary in 1934. His holdings expanded and the former private lands were returned to the Crown as part of the County of Cumberland Green Belt, then the Sanctuary became a Nature Reserve. Tipper built a small residence and an office which was originally from Camperdown Children’s Hospital and later used as a gatehouse at Government House in the domain. This was restored as a small museum and opened in 1982.
Oxford Falls
A diatreme occupies an open valley at Oxford Falls and is associated with a swarm of at least five igneous dykes up to 4m wide some of which can be traced about 3km. The diatreme was not identified until the 1960s when it was drilled to determine the available volume of aggregate that could be quarried. It consists of brown basaltic tuff and breccia. No quarry was ever developed.
The area has long been cleared and heavily disturbed by urban land use and there is little to be seen other than a small outcrop of weathered breccia in Oxford Creek and red clay soil derived from the breccia. A few cabbage palms give some indication of the original vegetation but most remaining plants are exotic weeds.
The dykes are generally oriented north-west and during the 1950s most were quarried to depths of about 4 or 5m along their length to recover kaolin, a layered silicate mineral, from the weathered rock. No fresh rock is visible and the former quarries have overgrown with native vegetation and can be difficult to locate without air photos.
Adjacent to the Wakehurst Parkway, Middle Creek cascades over a series of sandstone ledges about 25m high. This is possibly the highest waterfall In Sydney and occurs just upstream of where a large dyke crosses the creek. The top of the falls has several large potholes in the sandstone and is easy to reach from the creek crossing on Oxford Falls Road, the bottom of the falls provide a better view but it is a scramble to reach that point. During and after rain flow is so great that the ford on Oxford Falls Road can be closed.
Learn More
Muogamarra Nature Reserve (22mins)
References
Benson D. and Howell J. 1994. The natural vegetation of the Sydney 1:100,000 map sheet. Cunninghamia 3 (4) 679-787
Herbert C. 1983. Geology of the Sydney 1:100,000 Sheet 9130. Geological Survey of New South Wales. 225p
Access to Muogamarra Nature Reserve:
Muogamarra Nature Reserve is open to the public from 9am to 4.30pm for 6 weeks around August and September each year. The reserve is closed to the public at other times to protect sensitive natural and cultural heritage values.
To confirm availability or to enquire about any guided walks, please call the Kalkari Discovery Centre on the following numbers.
02 9472 9300
02 9472 9301
Contact hours: 9:30am to 4:30pm.
Or contact via email: snr.discovery@environment.nsw.gov.au