Crazy Deposition: Gold and Flooding
(All images courtesy of "Muskrat.")
Unseasonably high temperatures have hit the western and southwestern United States. In fact, it reached a high of 63 here in my part of northern New Mexico yesterday. The photos of flooding in Idaho you see in this post were sent in by "Muskrat," a long-time Bedrock Dreams reader and supporter. "Muskrat's" pics got me thinking again about flooding and gold deposition...therein lies the core of this post.
Excellent Gold Recovery Opportunities
Water is a powerful natural force and the "yin" to gold's "yang." Even in the most mundane or "normal" circumstances, running streams have the capacity to move gold around much more than you might think. Add the element of flooding (flash or otherwise) and you have a volatile mixture that can make for some pretty crazy gold deposition factors. This is especially true in dry or desert placers where rainfall is periodic at best and the name of the game is erratic gold deposition to begin with. One thing is certain, however. When flooding occurs, gold is going to get moved around in both wet and dry placer environments...alluvial and elluvial. Some of that gold will be buried beneath tons of rock, silt, and gravel while part of it will be uncovered or pushed into pockets and paystreaks that didn't exist before and that lie in some pretty unusual locations. Trust me on what I'm saying here...I've experienced this firsthand numerous times in my gold prospecting and mining career.
Although flooding is destructive by its very nature, it can provide some excellent gold recovery opportunities to those lucky small-scale miners who are first on the scene as those flood waters subside. Now none of us want our own property or that of others damaged by severe flooding, but if you truly have color running through your veins your heart should start pounding with excitement when flooding takes place in the areas you normally prospect or mine. Why? Simply because it presents a golden opportunity (pun intended!) for you to get some good gold in your poke. Is there anyone among you who wouldn't enjoy that prospect? I know I would...and do.
Wild Gold Deposition
In running streams and dry washes flooding can really mix things up. Large obstructions like boulders can get uprooted and moved out of place, bedrock can be scoured, and riverbanks and bench gravels undermined and swept into the current. Conversely, those same obstructions may remain in place if they are large enough and deeply buried but the banks, benches, and other gold-bearing gravels typically don't stand a chance when Ma Nature goes on the rampage. Bedrock, being a "fixed" entity, may not get scoured at all but may just pack up with even greater amounts of placer gold in the various gold traps its configured with. Elluvial gold may be uncovered and become visible to the naked eye or driven into rich pockets of gleaming yellow metal. The upshot? During severe flooding anything can happen and usually does.
While flood waters in running streams tend to drop slowly as the natural or man-made mechanisms of that flooding ease off bit-by-bit, flash flooding in dry washes and desert arroyos tends to be abrupt...both in terms of its initiation and its end. In these dry environments, any placer gold suspended and being roiled around by the awesome power of flash flooding will drop in place wherever it is when that flooding comes to an abrupt halt. That means the gold can be just about anywhere, from the surface right on down to bedrock. Ditto for placer gold in wet streams, although the flooding deposition factors are more gradual and therefore, more inclined to follow "normal" gold deposition factors. Notice I said "more inclined to." This doesn't mean some pretty wild gold deposition doesn't take place in flooded out streams and rivers because it does. But based on my own experience working post-flood wet placers, what you should be focused on is uncovered gold or shallow, newly born deposits. I've actually seen placer gold staring me back in the face where bedrock was exposed by flooding...quite a sight to behold, by the way. I've also recovered some very nice gold behind larger rocks or boulders that remained in place after flash flooding in dry washes. (When I use the term "behind" I mean the downstream side, OK?) I've also found gold scattered about in mixed gravels that were pulled down from stream and riverbanks during flooding events.
Hordes of Gold Seekers
Mud and rock slides can also be part and parcel of flooding events, although not in each and every context. These slides can be small or quite massive depending on the amount of rain associated with the flooding or the flooding itself. If those slides take place where gold abounds, then you can bet your sweet ass some of that gold that was "inaccessible" before it was either carried away by that slide has either been brought closer to the surface, or now lies scattered among the rocks, gravel, and mud of that slide. Multiple ounces of gold can be recovered from slides as was the case for two lucky miners I know who were first on the scene after severe flooding hit the North Yuba River in California some years back. All they needed to get that gold were their gold pans and a few hand tools. Again, I myself have literally plucked small nuggets and larger gold flakes off bedrock after large flooding events, not to mention cleaning out crevices that were literally packed with finer gold. That's the long and short of it, my friends.
After flooding of any consequence in gold country you should haul your ass out of bed, grab your gear, and get with the program. Not just because of the gold recovery opportunities that you'll be presented with, but because every other Tom, Dick, or Harriet with mining experience is going to be out there too. California's northern Motherlode Region is sparsely populated but after severe flooding along the North Yuba River I've seen literally hordes of gold seekers suddenly appear on scene within hours after flood waters subsided. A small percentage of these were locals, but the bulk of these folks were from Sacramento and the San Francisco bay area who'd driven hours to be in on the "take." So remember, when it comes to flooding and gold...you snooze, you lose.
(c) Jim Rocha (J.R.) 2015
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