I don't live in a mountain area, but that doesn't really matter, I'm sure people have asked this question beforez but my two questions are, what areas do I look in and how do I know I'm following the law of my state? How do I start my journey? I'm interested in trilobites and ammonites, and other stuff.
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What's the best area to legally find fossils (and how do I get started)
Probably a stupid question but how do people find fossils in general?
ELI5: How do archaeologist's know where to dig to find fossils?
ELI5: How do paleontologists know where to find fossils?
The art of fossil hunting is mostly the art of slowly walking a large desert area, looking for rocks that look a little different. At that point you can sweep away the bits. Fossil that are eroded from a hillside might all wash down the hill into a little pile of fossil bits; if you find one of those, you can probably trace where the original are from.
My brother-in-law showed me a place that (geologically) was a series of lava flows and then shallow lakes. In a railway cutting, you could find bits of those lakes, and it you split the rocks carefully, you would get fossil leaves (which was pretty cool).
Why does the "walk around and stare at the ground" work? Because fossils that are now just poking up out of the ground must have a history of first being on top of the ground (except for moles, I guess :-) ), then buried deeply, and now they are being re-exposed. That last bit means that the entire formation is being slowly eroded away; every year more fossils will be exposed and will probably just crumble away.
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