My name is Joshua Vise. When I was a child and teenager, I loved collecting fossils from outcrops near the my home in Missouri, not too far from the banks of the Mississippi. I have since moved to South Korea, and thought I’d restart this hobby. However, I am faced with a problem that I hope you could help me with. In the USA, I never learned really to identify rocks because the exposed outcrops where I would hunt for fossils were all sedimentary, with lots of shells and crinoids. In Korea, many areas are more forested, and sedimentary areas are intermingled with granite and other igneous formations.
I am able to distinguish sedimentary rocks from igneous and metamorphic rocks, but I’m unable to really identify what kinds of sedimentary rocks may be good sources of fossils. Most online resources are a bit redundant (saying something like “If fossils are present, it is sedimentary”), or don’t do much to help me identify these types of rocks in the field (saying things like “Fossils can be found in shales, limestones, and mudstones. Moreover, I am not sure that a field guide to rocks printed in English would be relevant here, because most of the field guides I have seen deal with North America. My questions for you are:
1. Is there a reliable way to identify shales, limestones, and mudstones just by sight? Are there consistent colors, textures, or shapes I could look for? Are there any tools or techniques that can help me?
2. Are rocks of these types consistent enough that a field guide to rock identification for the USA would be useful in Korea?
3. Are there any other resources you could suggest? I am definitely an amateur, but am always looking to learn.