Fossil fish are found in sedimentary rock.
A well preserved fossil fish is one of the prime quarries of marine fossil hunters. Marine fossils make up the vast majority of fossils from the geological time periods when much of the Earth was under warm, shallow oceans. The process of sedimentation facilitated the process of fossilization. Fish appeared in the Ordovician Period (438 to 505 million years ago) as one of the first chordate life forms -- the first organism with a face made up of eyes, a nose and a mouth. Fish continued to evolve through the Silurian Period and were the dominant life form during the Devonian Period, known as the Age of the Fishes.
Instructions
1. Check with your local chapter of a rock, gem, mineral or fossil club to acquire information about where fish fossils can be found close to your area. Research locations of marine fossiliferous deposits using the library and the Internet. Talk to a geologist at a nearby university or college for information. Acquire geological maps to locate the appropriate age and types of sedimentary rocks that might contain fish fossils. Study topographical maps for places where the rock might outcrop, exposing the fossils.
2. Make travel plans for a trip to the Green River Formation if you're serious about finding fossil fish. Educate yourself about the different species to be found on the ancient 50-million year old Eocene Epoch lake bed covering 25,000 square miles. Learn all you can about the topography of the lacustrine (lake) fossil zone in Wyoming, Colorade and Utah. Get detailed topographical maps of the area and study them to learn the lay of the land. Familiarize yourself with the stratigraphy of the fossil lake beds to determine which layers may have the most fossils.
3. Go to the Kemmerer, Wyoming, area, the center of the world's best fossil fish hunting grounds. Locate one of the several "U-dig" fish fossil quarries in the Kemmerer area. Pay the company a set fee for a certain number of digging and splitting hours. Scout out the quarry for the best place to dig for fossils. Search out easily accessible areas of exposed rock layers. Look for the 18-inch layer, known as the split-fish layer, above the oil-shale and coal-mudstone layer.
4. Put on your safety glasses and leather gloves. Chisel out the slabs in manageable sections from the quarry wall or floor with your pick and crowbar. Look for natural fissures and cracks in the rock to make their removal easier. Stack them up edgewise against the quarry wall or a large rock. Keep them in order in case you have to reassemble a large fish.
5. Examine the edges of the slabs for signs of fish fossils. Look for thin, very dark brown lines that contrast with the lighter colored stone. Crack the matrix rock open on one side of the fish with your hammer and chisel to reveal the mineralized skeletal remains. Split the rock following its natural fault lines. Break the smaller rock plates in half and check each one for fossil cross sections before discarding them.
Tags: fish fossils, fossil fish, with your, quarry wall, topographical maps
