Not really asking a question here as much as I'm thinking out load. However, would appreciate insight and comments from the professionals in forum.
I found a patch of really interesting ground in a stream. Was uncovered by recent flash flooding. I panned a bit of material from surface down to 6 inches or so. 2 full pans. Found notably more gold and electrum in this one spot (at the surface) then I've found elsewhere in this stream.
Sand is quartz with a large amount of magnetite. The magnetite gives ground a dark grey to black color. The quartz sand itself is translucent white. A few inches under surface, you start to see white quartz gravel and rock. No other types of rock or sand. Really homogeneous WRT variety. Rock density increases with depth. The rocks are all rounded, so likely came from somewhere else and settled there. Higher than normal concentration of gold (in this spot) could be due to the fact that gold is found in white quartz in this region.
The ground composition in this one patch is really odd. It's VERY different from immediate surroundings. Both upstream and downstream ground is composed of various clays with iron oxides, aluminosilicates, manganese, and a hodgepodge of other types of mineralization. In rest of stream, rocks are varieties of metamorphic and igneous. Good variety of stuff.
If the quartz in this one spot traveled downstream from somewhere else, I'd expect that the rest of the stream would look at least somewhat similar, but it doesn't ... now that I'm thinking about it, I might have seen similar sand on other side of stream but attributed the color to organic matter.
Given the above, seems like a plausible rationale for what I'm seeing is that there was another stream in distant past that ran almost perpendicular to this stream's current path. Evidence of this old stream could have been (mostly) eroded away by current stream's path. If so, I need to find the old waterway's "upstream" side and start looking for quartz outcropping near surface level.
Anyone ever encounter something similar?
I found a patch of really interesting ground in a stream. Was uncovered by recent flash flooding. I panned a bit of material from surface down to 6 inches or so. 2 full pans. Found notably more gold and electrum in this one spot (at the surface) then I've found elsewhere in this stream.
Sand is quartz with a large amount of magnetite. The magnetite gives ground a dark grey to black color. The quartz sand itself is translucent white. A few inches under surface, you start to see white quartz gravel and rock. No other types of rock or sand. Really homogeneous WRT variety. Rock density increases with depth. The rocks are all rounded, so likely came from somewhere else and settled there. Higher than normal concentration of gold (in this spot) could be due to the fact that gold is found in white quartz in this region.
The ground composition in this one patch is really odd. It's VERY different from immediate surroundings. Both upstream and downstream ground is composed of various clays with iron oxides, aluminosilicates, manganese, and a hodgepodge of other types of mineralization. In rest of stream, rocks are varieties of metamorphic and igneous. Good variety of stuff.
If the quartz in this one spot traveled downstream from somewhere else, I'd expect that the rest of the stream would look at least somewhat similar, but it doesn't ... now that I'm thinking about it, I might have seen similar sand on other side of stream but attributed the color to organic matter.
Given the above, seems like a plausible rationale for what I'm seeing is that there was another stream in distant past that ran almost perpendicular to this stream's current path. Evidence of this old stream could have been (mostly) eroded away by current stream's path. If so, I need to find the old waterway's "upstream" side and start looking for quartz outcropping near surface level.
Anyone ever encounter something similar?
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