22°S 139°E Manganese Ridge – Queensland by Degrees

AT THE POINT

Degree Confluence 22°S 139°E, Google Earth

site

n

Looking north

e

Looking east

s

Looking south

w

Looking west

 

Rocky ground surface at the confluence

Location: Degree Confluence 22°S 139°E is on Manganese Ridge, in the heart of the Barkly Tableland in western Queensland. The confluence itself is unmarked, and located just over 2 km east of a dirt track which was accessed from the Diamantina Developmental Road, 60 km to the east. The nearest settlement is Dajarra, which is approximately 63 km to the north-east. The site was visited by a party of RGSQ members travelling in four 4WD vehicles from Brisbane in May, 2008.

Landscape: The view from the confluence shows gently undulating terrain, with an elevation of approximately 225 m. The hills of Manganese Ridge, from where the site takes its name, can be seen in the distance towards the east.

Numerous stones almost completely cover the surface; underneath is red soil. Low bushes and some tussocks of grass are present at the confluence. Trees are widely scattered in the vicinity of the point, and more closely spaced along nearby creeks. Quita Creek is just to the east and south. Quita Creek, and other watercourses in the area flow into the Georgina River, 37 km to the south-west. All drainage in the degree square is part of the Eyre Basin.

Geological features of the confluence and its surrounds include Middle Cambrian formations, such as sandstone, calcareous sandstone and chert, and limestone.

Point Photo Credits: Paul Feeney

Point Information By: Jo Grant

IN THE DEGREE SQUARE

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Climate: The closest representative weather station to the confluence is at Urandangi, which is 83 km to the north-west of the degree confluence, and has an elevation of 174 m. The station has been recording data since 1891.

 

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Year

Mean max
(ºC)

38.5

37.2

35.7

32.4

27.5

24.3

24.0

26.7

31.3

35.1

37.5

38.8

32.4

Mean min
(ºC)

24.0

23.4

21.1

16.7

12.0

8.4

7.0

8.8

13.0

17.6

20.6

22.8

16.3

Mean rain
(mm)

62.2

63.9

41.9

13.2

12.5

9.5

9.0

4.5

6.2

14.4

21.1

38.9

297.7

              

The highest temperature recorded was 47.0°C in December 1979, and the lowest was -2.0°C in both June 2002 and July 1984. The greatest rainfall recorded in a year was 925.2 mm in 1950, and the lowest was 29.5 mm in 1928. These and other climate statistics for Urandangi can be found at: Australian Bureau of Meteorology, http://www.bom.gov.au/climate/averages/tables/cw_037043_All.shtml.

Extremes of Nature: Despite the area's inland location, it is still subject to the impact of some cyclones. The database maintained by the Bureau of Meteorology shows that seven cyclones have passed within 200 km of the confluence since 1906, one of which passed within 50 km (an unnamed TC in 1940). Even distant cyclones bring with them potentially destructive winds and intense rainfall. Cyclone information for this area and all of Australia can be found at the Australian Bureau of Meteorology website, http://www.bom.gov.au/cgi-bin/silo/cyclones.cgi.

cyc

Cyclones tracked, BOM

Like most places in the Australian tropics, extreme heat is also a danger. Records show that the Urandangi Station experiences 152 days annually with temperatures 35°C or warmer, 53 days of which 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. With a low average rainfall, and only 31 days a year with any precipitation, the area is also among the driest in Australia.

Today:

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


Information: Ken Granger

Edited by: Hayley Freemantle

REFERENCES

Geoscience Australia, NATMAP Raster

Geoscience Australia, Scanned 250 K Geology Maps