Skip to Content

<

Welcome Mine

Hidden : 01/02/2011
Difficulty:
1 out of 5
Terrain:
3 out of 5

Size: Size: not chosen (not chosen)

Join now to view geocache location details. It's free!

Watch

How Geocaching Works

Please note Use of geocaching.com services is subject to the terms and conditions in our disclaimer.

Geocache Description:

Welcome mine is located on the road linking Arkaroola to Paralana Hot Springs. "The guys were out here from about the 1860s for about three years - they dug a fair bit of ore out and carted it off straight away and had it processed. They made a big profit out of it. They didn't keep digging to find more - they got out at the right time." [1]

Leave your vehicle at the designated car park and walk up the hill through the historic mine. At Ground Zero, you will find an accessible mine shaft which descends 2m and then continues a few meters with only a slight slope. It is a pleasant place on a hot day, as underground temperatures average over the whole year. Besides the history, discover the geology and the texture of the different rock plugged with minerals. Enjoy the earth colors which are particularly rich at this place. Please take memories and souvenirs only with your camera and leave rocks and minerals in place for coming geocachers, as they would decompose anyway in a different climate.

Tell-tale green colorations of copper mineralization splattered on various outcrops about Arkaroola must have been known to the aboriginal people since time immemorial. Not unexpectedly in this arid climate, deeply weathered, secondary oxidized copper minerals provide abnormally colorful and eyecatching displays. Green malachite, apple green atacamite, dark blue azurite, sky blue chrysocolla, red cuprite and metallic native copper occur in varying abundance around many of the old mine workings. Red haematite laced with green malachite appears in specular rock textures. [2]

Not surprisingly, the search for copper goes back a long time. The rich Burra Burra and Kapunda discoveries quickly fired the the discovery of the Yudnamutana field in the middle of the 19th century. During the first few years, new discoveries included such mines as The Daly, Sir Dominic, Wheal Austin, Wheal Frost, The Welcome and many others.The mid 1860's Great Drought greatly curtailed activity and operations all but ceased in the fields in 1869. Thereafter, prospecting or mining has continued sporadically but unsuccessfully right up to the present. [2]

The Adelaidean Trough was initiated almost 1000 million years ago through where now stands the Flinders and Mount Lofty Ranges, forming the so-called Adelaide Geosyncline. It literally grew and extended in at least five major stages extending into the Cambrian Period, 500 million years ago. The oldest or Willouran phase was one of widespread downfaulting in the north and voluminous volcanic outpourings along a north-east to south-west fissure that originally lined up with the trend of the modern east coast of Eyre Peninsula. A series of deep local fault valleys or graben filled with both basaltic lavas and sediments. Early on, the sea entered these valleys depositing limestones. Much of the volcanism was submarine so that frothing lavas became lathed with cracks and steam vesicles . The most likely scenario for the genesis of the mineral deposits involves circulation of basinal fluids and ore precipitation through neutralization by fluid-rock interaction with the dolomitic shales hosting the mineralization. [2]

Logging:

To log this earthcache, you physically have to come to this place and answer a few questions:

Q1: Into how many corridors splits the main shaft?

Q2: The hand-cut termite resistant mulga logs used to shore up the shafts have stood the test of time. How many of them support the ceiling?

Q3: List the colors of the rock!

Q4: What kind of animals live here?


Please be cautious entering the mine - you are doing so at your own risk

References:

[1] Doug Sprigg, featuring in “Arkaroola's mining history: Keith explores the Outback region of South Australia”, Channel 9 South Australia Pty Ltd & WIN Corporation Pty Ltd (2006)

[2] Reg C. Sprigg: "Arkaroola - Mount Painter in the Northern Flinders Ranges, S.A.: The Last Billion Years" (1984) Gillingham Printers Pty Ltd, Underdale, Australia

Further reading:

Wikipedia: “Adelaide Geosyncline”

Ian A. Dyson: “Geology of the eastern Willouran Ranges”, MESA Journal 35 (2004), p. 48-56.

Brugger, J.; Ogierman, J.; Pring, A.; Waldron, H.; Kolitsch, U.: “ "Origin of the secondary REE-minerals at the Paratoo copper deposit near Yunta", South Australia” Mineralogical Magazine, Volume 70, Number 6, (2006 ), p. 609-627.

Additional Hints (Decrypt)

whfg tb gurer naq unir n ybbx!

Decryption Key

A|B|C|D|E|F|G|H|I|J|K|L|M
-------------------------
N|O|P|Q|R|S|T|U|V|W|X|Y|Z

(letter above equals below, and vice versa)



Return to the Top of the Page

Reviewer notes

Use this space to describe your geocache location, container, and how it's hidden to your reviewer. If you've made changes, tell the reviewer what changes you made. The more they know, the easier it is for them to publish your geocache. This note will not be visible to the public when your geocache is published.