|Latitude & Longitude (WGS84):||27° 19' 11'' South , 121° 3' 50'' East|
|Latitude & Longitude (decimal):||-27.31978,121.06379|
|Locality type:||Group of Prospects|
|Köppen climate type:||BWh : Hot deserts climate|
Some geologists get very excited about regolith. We are talking here about clays, sediments, alluvium etc. As gold was found in the Bronzewing area in this material, it is time I am afraid to face this subject. While Sundowner is an anomalous gold prospect, the source succeeds to filling several pages of regolith description without mentioning gold once for Sundowner.
The Sundowner prospect is 12 kilometres north-east of the Bronzewing Gold Mine, and just north of Bates Creek.
The transported overburden at the prospect is 100 metres deep. The top 50 metres is similar in composition to that found at Bronzewing, except with the addition of more feldspar and coarse quartz from a granite area to the north-west.
Below the 50 metre mark is puggy goelithic clay, dominated by small 0.5 to 5 mm spherical pisoliths, with cores of either hematite-maghemite, Fe clay, organic debris, quartz or a mix of these. Between the two lithologies described above is an 8 metre band of Fe gravels.
Soils in the sediments contain quartz grains, hematite, kaolinite and minor feldspar, muscovite and calcite. The clays described above range from dark brown to reddish maroon, consisting of hematite, quartz, kaolinite and minor goethite, with some hematite pseudomorphing after wood fragments.
At the 60 to 90 metres mark the clays also contain laterite nodules, pisoliths, duricrust, collapsed mottled saprolite, mottled saprolite, Fe saprolite, saprolite and then bedrock.
Nodular angular and platy fragments of mottled saprolite is composed of hematite, goethite, kaolin, gibbsite, quartz and anatase. The nodules are sometimes pseudomorphs of primary minerals. Also contained in the mottled saprolite is red, hematitic, tabular Fe fragments 10-70 mms across.
In the upper level of the saprolite, weathering has created voids, and when these amalgamate causes the saprolite to collapse. This forms then a condensed residual horizon. Nodules within this horizon are yellowish brown but are dark brown or black above this.
Fe saprolite is yellowish brown or reddish brown of kaolin impregnated by goethite. The upper saprolite contains cream, light yellow and grey clays of kaolin, smectite and quartz.
Near the base is creamy buff, light green, or khaki cream coloured clays and saprolite fragments with weathered chloritic basalt passing into fresh bedrock. The lower part of the saprolite contains chlorite, feldspar, quartz, calcite, mica and pyrite.
11 valid minerals.
Rock Types Recorded
Select Rock List TypeAlphabetical List Tree Diagram
Entries shown in red are rocks recorded for this region.
This geological map and associated information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the complete geology at this locality but it gives a background for the region in which it is found.
Click on geological units on the map for more information. Click here to view full-screen map on Macrostrat.org
0 - 2.588 Ma
Age: Pleistocene (0 - 2.588 Ma)
Comments: regolith; synthesis of multiple published descriptions
Reference: Raymond, O.L., Liu, S., Gallagher, R., Zhang, W., Highet, L.M. Surface Geology of Australia 1:1 million scale dataset 2012 edition. Commonwealth of Australia (Geoscience Australia). 
|Neoarchean - Mesoarchean|
2500 - 3200 Ma
|Archean sedimentary and volcanic rocks|
Age: Archean (2500 - 3200 Ma)
Comments: Yilgarn Craton
Reference: Chorlton, L.B. Generalized geology of the world: bedrock domains and major faults in GIS format: a small-scale world geology map with an extended geological attribute database. doi: 10.4095/223767. Geological Survey of Canada, Open File 5529.