24°S 140°E Coorabulka – Queensland by Degrees

AT THE POINT

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Degree confluence 24°S 140°E, Google Earth

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n

Looking north

e

Looking east

 

s

Looking south

w

Looking west

 

DRAFT VERSION - More information to come

Location: Degree Confluence 24°S 140°E is in Channel Country in western Queensland, on the working property, 'Coorabulka', after which the degree square is named. The closest settlement is Bedourie, approximately 67 km to the south east. While the confluence itself is unmarked, a GPS was used to find its exact location (accurate to within a few metres). Although there is no direct access to the point, freshly graded property tracks passed 2 km to the north of the point, and the rest of the journey was across country by 4WD. The site was visited in the late morning by a party of RGSQ members travelling in four vehicles from Brisbane, in June 2009.

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Crossing a drainage gully on the way to the point

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Expedition members standing on the degree confluence

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Grassy plains and creeks surrounding degree confluence 24°S 140°E (Google Earth Image)

Landscape: The view from the degree confluence shows a completely flat terrain, with an elevation of 100 m. A property fence is visible nearly 2 km to the south-east, and the only other notable features are a few shrubs (height 2/3 m). Surface material is good pasture grass on top of very soft soil that made access to the point potentially risky, especially due to recent rains. No animals were sighted at the point, although some kangaroos were seen in the surrounding countryside.

The geology of much of the country to the west along the course of the large creeks (eg. Georgina River) is Undifferentiated Cainozoic alluvium, and is subject to inundation after heavy rains. Even numerous pools and wet patches present even during the dry season. Less than 2 kms to the east of the confluence is a sizeable area of Mesozoic Lower Cretaceous gravel, sandstone, siltstone, and limestone.

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Nr 8 Bore on Coorabulka Property

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Another drainage gully at camp, on the property

Point Photos By: Paul Feeney, Mary Comer

Point Information By: Paul Feeney, Jo Grant, Mary Nowill

IN THE DEGREE SQUARE

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Climate: The closest weather station is at the Bedourie Police Station, which is approximately 67 km south-west of the degree confluence, and has an elevation of 91 m. The station has been collecting data since 1932.

 

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Year

Mean max
(ºC)

38.8

38.1

36.2

32.5

26.8

22.6

23.3

25.5

30.8

34.1

36.3

38.4

32.0

Mean min
(ºC)

25.1

24.6

21.7

17.4

11.7

8.2

7.6

9.1

14.4

17.9

20.9

23.5

16.8

Mean rain
(mm)

33.4

35.3

17.6

10.1

11.6

10.0

10.3

7.2

6.3

14.1

16.2

16.2

187.7

The highest temperature recorded was 47.0°C in January 2004, and the lowest was 1.6°C in July 2004. The greatest rainfall recorded in a year was 485.1 mm in 2000, and the least was 33.4 mm in 2002. These and other climate statistics for Bedourie can be found at: Australian Bureau of Meteorology, http://www.bom.gov.au/climate/averages/tables/cw_038000_All.shtml

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Cyclone tracks within 200 km of the confluence, 1906 to 2006 (Bureau of Meteorology web site)

Extreme heat and drought are also serious issues. Records show that Bedourie experiences 139 days annually with temperatures over 35°C, 49 of which typically reach 40°C or warmer. 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. In addition, with very little rainfall and only 21 days a year on average with any rain, the area is also among the driest in Australia.

Extremes of Nature: The area experiences extreme heat for much of the year, with Bedourie having an average of 139 days annually that have maximum temperatures equal to or over 35°C. The hottest months are December to February, all of which experience on average over 20 days with temperatures equal to or over 35°C. With an extremely low average rainfall and only 21 days a year with any rain, the area is also among the driest in Australia.

Today:

The population of the degree square at the 2011 national Census was less than 50.

MEASURE

1996

2001

2006

2011

Total population

107

23

22

<50

Total males

66

16

13

0

Total females

41

7

9

0

Under 5 years

12

3

3

0

65 years and over

3

0

4

0

Indigenous

48

6

4

0

 

Edited by:  Hayley Freemantle

Information: Ken Granger

REFERENCES

Geoscience Australia, NATMAP Raster

Geoscience Australia, Scanned 250 K Geology Maps