20°S 142°E Saxby River – Queensland by Degrees

AT THE POINT

Degree confluence 20°S 142°E, Google Earth

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n

Looking north

e

Looking east

s

Looking south

w

Looking west

 

Location: This confluence point is on the property called Debella Station. Getting to the site was by vehicle from Julia Creek to Debella Road, then 3km on station tracks and the final 1.3kms on foot. This point is located in the McKinlay Shire with Julia Creek, 77km to the south-west, being the closest settlement.

The Landscape: The braided channels of the Saxby River are provide the drainage at the point. The Saxby River flows to the Flinders River and then to the Gulf of Carpentaria. The landscape is a flat alluvial plain with an elevation of 140m ASL.  The soil is a reddish sandy clay derived from the Cainozoic age (less than 66 million years) sand plain that is the geology at the point. Scattered Eucalypts (including Bloodwoods, Coolibah and River Red Gums), grasses, Creek Wilga (Eremophila bignoniiflora) and Ruby Saltbush (Enchylaeca tomentose) were noted in this area. Fauna in the form of macropods are found in this region. The land use is mainly by cattle grazing.

gps

GPS

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Bloodwood near the point (Mary Nowill, 2010)

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Insectivorous Plant

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Lots of spiders in the area

 

Reaching the point was not without its dramas. One of the team misjudged the ground near a borrow pit and ended up well bogged. He was recovered by other members of the party.

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Bogged! (Mary Nowill, 2010)

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Recovery! (Mary Nowill, 2010

Point information and photos: T Hiller, N O' Connor and J & M Nowill 17/6/2010

WITHIN THE DEGREE SQUARE

The Country: The landscape across the square is dominated by the flood plain of the Flinders River and its major tributary the Saxby River. These streams have wide, shallow, braded channels that flow to the north-west on their way to the Gulf of Carpentaria. Elevations range from around 150m ASL in the south-east corner sloping down to 50m in the north-west.

The oldest geology in the square is the Albian age (around 100 million years) sandstone and siltstone that make up the southern third of the square. The majority of the square is also sedimentary material (sandstone, siltstone and mudstone) of more recent origin including a large area of Pleistocene age (around 2.6 million years) sandstone in the north-east quadrant. The floodplains that cross the square from south-east to north-west are Quaternary age (less than 1.6 million years) alluvium of sand and gravel.

Vegetation across the square is predominantly grassland with Kangaroo Grass (Themeda triandra), Curly Mitchell Grass (Astrebla lappacea) and spinifex (Triodia spp) providing the main ground cover. Scattered eucalypts dot the plains and denser riparian woodlands of River Red Gum (Eucalyptus camaldulensis) and Coolibah (E. coolabah) are found along most drainage channels. Prickly Acacia (Acacia niloticus), which was introduced in the 1890s has become a serious pest species across the area.

There is a rich bird life across the square including Emu, Brolga, Black Kite, Galah, Corella and Zebra Finch. The larger mammals include the Northern Whiptail Wallaby and Common Wallaroo. A wide range of lizards and snakes are also found including Gould's Monitor and Death Adder.

Land use across the square is dominated by cattle grazing.

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The Climate: The climate of the square is classified as grassland with a winter drought. The closest representative Bureau of meteorology climate station is at Julia Creek, which is approximately 78 km to the south-south-west. This station has an elevation of 123 m ASL and has been recording data since 1912.

 

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Year

Mean max
(ºC)

37.6

36.4

35.6

33.5

29.7

26.8

26.5

29.0

32.5

36.0

37.9

38.3

33.3

Mean min
(ºC)

23.8

23.6

21.5

18.2

14.3

10.3

9.1

10.9

14.4

18.7

21.3

23.0

17.4

Mean rain
(mm)

121.6

113.7

55.6

16.9

15.0

12.0

7.8

2.4

5.3

15.7

29.9

67.5

458.8

The highest temperature to be recorded at Julia Creek was 46.5°C in November 1965, and the lowest was -0.9°C in June 1965. The greatest rainfall recorded in any year was 1083.9 mm in 1974, and the least was 105.6 mm in 1952.

Extremes of Nature: The area is subject to the impact of tropical cyclones. The database maintained by the Bureau of Meteorology shows that in the 100 years from 1906, 16 cyclones passed within 200 km of the confluence, although only one passed within 50 km (TC Brownyn in 1972). These and distant cyclones bring with them potentially destructive winds and intense rainfall that will lead to extensive flooding that will isolate the area for extended periods.

 

Cyclone tracks within 200 km of point 1906 to 2006 (Bureau of Meteorology web site)

The area experiences between 30 and 40 thunder days each year. Severe thunderstorms can bring destructive winds, intense rainfall causing localised flooding and lightning strikes that can spark bushfires if there is sufficient fuel available.

Extreme heat is also a danger. Records show that the Julia Creek experiences an average of 154 days annually with temperatures 35°C or warmer and 35 days of which can 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 details of two earthquakes with epicentres within the square. They were a ML 3.8 event on 4 July 1994 located in the north-west corner of the square and a ML 4.2 event on 5 July 1994 located just south of the Flinders River near the western edge of the square. No damage was recorded from these two earthquakes.

The Indigenous Story: Most of the land within the square is the traditional country of the Ngawun people.

MORE INFORMATION WELCOME

European Exploration and Settlement: It is possible that the first European to travel through or close to this area was Ludwig Leichhardt in 1848, the expedition from which he never returned. Two trees marked with Leichhardt's typical "L" blaze were found in the area by cousins Donald and Duncan McIntyre who explored and took up land along Julia Creek in 1864. John McKinlay's party also passed through the area in 1862 after having found the graves of Grey, Burke and Wills on Cooper Creek.

MORE INFORMATION WELCOME

Today:  

The total population of the degree square at the 2011 national Census was 289. The apparent increase in population between the last two censuses is probably due to changes in census boundaries.

MEASURE

1996

2001

2006

2011

Total population

165

132

139

289

Total males

105

86

81

144

Total females

60

46

58

145

Under 5 years

14

6

13

27

65 years and over

0

5

6

30

Indigenous

4

3

0

0

Land use across the square is dominated by cattle grazing. This industry is supported by a network of 1150km of public roads and an even larger network of private station roads and tracks. All roads in the square are natural surface and subject to closure following rain. Most stations have their own airstrips.

The square falls mostly within McKinlay Shire. There is a small section of Richmond Shire along the eastern side of the square. There are no national parks in the square.

Site Summary:

Location

On Debella Station close to Saxby River

Access

By vehicle on public roads and station tracks; the final 1300m on foot

Nearest settlement

Julia Creek is 77km to the south-west

Terrain

Flat flood plain

Catchment

Saxby River which flows to the Flinders River and the Gulf of Carpentaria

Geology & soils

Alluvium of Quaternary age

Vegetation

Low scrub with scattered trees; grass groundcover

Land use

Cattle grazing

Climate

Grassland with a winter drought

Population in degree square

139 at the 2006 census

Infrastructure

1150km of public roads, private roads and tracks, station airstrips

National Parks

None in the square

 Compilers: Ken Granger and Jo Grant  2010

Edited by: Hayley Freemantle

References: various web sites including local governments, Xtrata and Bureau of Meteorology.

EPA 2001: Heritage trails of the Queensland outback, Queensland Environmental Protection Agency, Brisbane.

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