Location: This confluence point is on the property called Glenora Station. Getting to the site was along vehicle tracks to the abandoned Glenora homestead site, then by vehicle 1km across country with the final 2.5km being on foot. The nearest populated place is Georgetown in Etheridge Shire some 98km to the north-east. The point lies within Croydon Shire.
The Landscape: The sits at the headwaters of the Yappar River which flows into the Norman River and these to the Gulf of Carpentaria. The landscape around the point consists of dry water courses and stony ridges. The elevation at the point is 306m ASL. The soil is a grey sandy soil with ridges and outcrops of sandstone and conglomerate of Jurassic origin (200 to 146 million years). The vegetation is dominated by Eucalyptus miniata (Darwin Woollybutt), Acacias and some Spinifex on the ridge tops.There are also large paperbarks along the Yappar River. There is prolific bird life along the river, with feral pigs and macropods also be seen. The land use is mainly cattle grazing.
Point information and photos: T Hiller, N O' Connor and J & M Nowill 16/6/2010
WITHIN THE DEGREE SQUARE
The Country: This square is bisected by the Gregory Range that runs diagonally across the square from south-east to north-west. It has a maximum elevation of 706m ASL in the south-east corner and ranges down to around 200m ASL in the north-west. The northern end of the range has a geology of Mesoproterozoic Idalia rhyolite (1600 to 1000 million years) and small areas of Palaeoproterozoic mudstone of the Candlow Formation (25000 to 1600 million years. The south-eastern end of the range, by contrast, is made up of much more recent sandstone of Jurassic age (200 to 146 million years). On the floodplains to the west of the range the geology is even younger sandstone of Pliocene age (around 5.3 million years). The landscape on the range includes areas of steep-sided cliffs and mesa-toped formations as well as highly folded formations that produce a very rugged topography.
The range is dissected by drainage channels with the Gilbert and Robertson Rivers flowing to the north while to the west the various tributaries of the Norman River, including the Yappar, and Clara Rivers and Esmeralda Creek. The lowest point on these floodplains is around 140m ASL where the Yappar River leaves the square. Perhaps the most spectacular feature of the drainage network is Cobbold Gorge on the Robertson River which cuts through spectacular sandstone cliifs.
Vegetation across the square ranges from mid-height open forest similar to that at the point to open to savannah and grasslands on the western floodplains. Most streams have dense riparian forest often dominated by River Red Gum (Eucalyptus camaldulensis) and Coolabah (E. coolibah). Fauna is similar to that at the point and land use is dominated by cattle grazing.
The Climate: The climate of the area is classified as being grassland with a winter drought. The closest representative weather station is at the Georgetown Post Office, which is approximately 97 km to the north-east of the degree confluence, and has an elevation of 292 m. The station has been recording data since 1872.
The highest temperature recorded at Georgetown was 43.5°C in January 1994, and the lowest was -3.0°C in July 1974. The greatest rainfall recorded in a year was 2 045.7 mm in 1974, and the least was 308.4 mm in 1926.
Extremes of Nature: The area is subject to the impact of tropical cyclones. The database maintained by the Bureau of Meteorology shows that 32 cyclones have passed within 200 km of the confluence since 1906, four of which passed within 50 km (an unnamed TC in 1914, TC Agnes in 1956, TC Brownyn in 1972, and TC Paul in 1980). Even distant cyclones can bring with them potentially destructive winds and intense rainfall. The intense rainfall can produce severe flooding that will spread across the lower floodplains and dangerous flash flooding in the steeper country.
Cyclone tracks within 200 km of point 1906 to 2006 (Bureau of Meteorology web site)
The area experiences on average between 20 and 30 thunder days a year. The more severe thunderstorms can produce intense rainfall and localised flash flooding, destructive winds (including tornadoes) and lightning strikes that can spark bushfires if there is sufficient fuel to sustain spread.
Like most places in the Australian tropics, extreme heat is also a danger. Records show that the Georgetown Station experiences 110 days annually with temperatures 35°C or warmer, although very few of these reach over 40°C. Such extreme temperatures can cause heat stroke and death if appropriate measures are not taken such as avoiding strenuous physical effort, keeping as cool as possible and drinking lots of water. Heat waves kill more people in Australia than all other natural hazards combined.
The National Earthquake Database maintained by Geoscience Australia contains no earthquakes that have been recorded with the square since 1900.
The Indigenous Story: The land within the square is the traditional country of several Aboriginal groups including the Yanga, Mayi-Kulan and Ngawun.
It is clear that there was conflict between the Aboriginal people of the area and the early European settlers given the inscription of the grave of John Corbett at the mouth of Cobbold Gorge:
Sacred to the memory of John Corbett who's body is interred here and here was murdered by the blacks on 31st May 1871...
It is likely that Corbett, a store keeper from Cloncurry, was murdered and robbed of gold by one or more Europeans though the blame was laid on the Aboriginals.
MORE INFORMATION WELCOME
European Exploration and Settlement: The first European to travel through this square was Augustus Gregory in 1855-6. William Landsborough may also have passed through or close to the area during his expedition in search of Burke and Wills in 1861-2.
Pastoralists probably entered the area in the 1880s and prospectors also flocked to the area during the Croydon gold rush.
MORE INFORMATION WELCOME
The combined populations of this degree square and its neighbours at the 2011 National Census was 347, though certainly not all are located within this square.
Most of the population are employed in the pastoral industry and live on disbursed cattle stations.
The square is divided almost evenly between Etheridge and Croydon Shires with the boundary running along the crest of the Gregory Range. A very small section of McKinlay Shire is in the south-west corner. There are no national parks in the square.
There are 580km of public roads in the square, all of them with a natural surface that may make them impassable in wet weather. There is an even larger network of private station roads and tracks as well as several private airstrips. Telecommunications are available in the area via a network of microwave relay stations.
Compiled by: Jo Grant and Ken Granger, 2010
Edited by: Hayley Freemantle
References: various web sites including local governments, QPWS and Bureau of Meteorology.
EPA 2001: Heritage trails of the tropical north, Queensland Environmental Protection Agency, Brisbane.
Philip Moore, 2005: A guide to plants of inland Australia, New Holland.