Saturday, November 19 2022
If you’re used to water mining, having success in the desert might seem challenging— that is until you start thinking of desert ground as a massive sluice box. Many of the principles you’re used to when prospecting and mining in waterways, will translate into desert mining. The most important thing to remember is that water is crucial to gold movement. Unlike a running river or creek with highs and lows, desert placers are much different in that gold is moved quickly during a flash flood, leaving gold stranded as opposed to being moved further by continual water flow in a creek. During a river high-water event in a non-arid area, gold is moved over a larger area by massive water flows that continue until the water slows as the source dissipates its energy. Spring snow runoff is a good example. Rivers rise and sometimes flood based on the upstream water source. When the snow has melted, the river will slowly get back to normal. In the desert, gold is moved in the exact same way with the exception that water powerful enough to move gold does so and then just simply stops. In a flash flood, gold is moved very violently and often a very short distance, sometimes percolating into valuable pockets. Here’s where the difference between water and desert mining principles comes into play generally flood gold will concentrate in areas that do not meet the standard thought of inside bends and where the water flow becomes lower. For the most part, desert mining experts recommend staying out of the washes, gulches and dry river beds— that is unless you clearly see exposed bedrock. Gold will settle fairly quickly when it is trapped behind jagged bedrock and small fault lifts that have not been worn down over time by constant water flow. It IS true you can find areas of concentrated gold-bearing material in the washes, however, the amount of time and energy to get through feet of overburden is usually just not worth it, especially when there are higher values to be found outside of the wash. Follow the leads out of the wash to where the gold lives in higher concentration. Test and sample areas you see with a great deal of runoff from a tributary coming into the main wash. Here you are only digging through the current flood layer and testing for flood gold. Make your way out of the wash carefully looking at the bottom of the tributary and the areas where the water flowed into the tributary. Look closely for jagged bedrock and slight lifts in the ground and then prospect. Continue to test each of those spots. What started as a few specks of flood gold in the main wash can lead to larger and larger deposits on the flats or in slight inclines across the desert floor. Keep in mind that when a flash flood is dissipating, there is not enough energy to move a lot of rock, but the sand will continue to flow a bit, creating great clues. In general, cool season precipitation (October through April) is the most extensive source of rain in the desert regions. Rainfall is more widespread and of relatively long duration during the cool season. On the other hand, warm season precipitation (May through September) results largely from short monsoon-type thunderstorms. If you’re ready to head to a sunnier climate this winter, keep these tips in mind and you just might find enough similarities between water and desert mining to make you return every year. Good luck! |
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