Karalee Rocks and Dam is located off the Great Eastern Highway 34 km east of Southern Cross, heading towards Kalgoorlie, (18 km past Yellowdine Roadhouse). Turn left and continue on gravel for 4.2 kms.Karalee Dam was constructed to provide water for slow steam trains en route to Kalgoorlie. The site was chosen mainly because of the granite outcrop; with rain the outcrop becomes a natural catchment area. Construction between 1896–1897, its capacity 10.6 million gallons, 1487 feet above sea level and 25 feet in depth. Retaining walls of granite slab, all cut from the top of the rock and laid by hand, surround the enormous rock catchment.
This enables the water to flow off the rock into the dam via a large semi-circular aqueduct of steel, hand riveted at each joint, which is still in very good condition considering its age and the natural harsh elements. To reflect upon the unbelievable manual labour and horsepower involved in this construction, is well worth the journey.
There are in fact two main granite rock massess at Karalee Rocks and Dam; at the interpretative sign at the start of the sign are directions to both rocks. The stated co-ordinates for this earthcache are at the main rock and this is accessed by walking along the walking track. The waypoint co-ordinates are at the start of the walking track.
On the rock and surrounding rock face you will find multi-coloured patterns on the rock which look like pain blotches but are actually lichens, mosses and algae. Some mosses are more pronounced in the Winter months. The lichens play a part in the breakdown of granite rocks. They secrete very weak acids that slowly loosen the tiny sand grains in the rock surface. The root like rhizoids of mosses also help loosen sand grains. Both mosses and lichens trap dust, sand and other materials. When they die, this matter adds to a seed bed for larger plants. As the surface changes, different type of plants can grow on the rock. This progressive change of plant communities is called “succession”. There are good examples of this cycle at the stated co-ordinates. It will be noted the surrounding area and track in from the main highway is very sandy which is the product of the granite rocks breaking down over many years.
Granite outcrops of Western Australia are inselbergs and monoliths made from granite and are found across much of Western Australia. Granite is a light-coloured igneous rock with grains large enough to be visible with the unaided eye. It forms from the slow crystallization of magma below Earth's surface. Granite is composed mainly of quartz and feldspar with minor amounts of mica, amphiboles and other minerals.
To log this cache, go to the listed coordinates and email me the answers to these questions. You can immediately log the find and if there are any problems I will contact you.
1. Estimate the approximate size of the main rock formation visible from the co-ordinates.
2. Where are the lichens and mosses mostly found on the rock? (In dry periods there will be evidence of dried mosses and lichens).
3. Is there other evidence of erosion from the rocks?