Other Areas

Any exposure, natural or artificial, is worth looking into. Any area known to have produced fossils, even in the most built-up areas, may at some time have a construction project that will again expose fossil-bearing rocks. Some likely places are described here. House and office-building excavations

During construction of building foundations in downtown Kansas City a number of years ago, a layer of shale was dug out that was loaded with superb crinoid crowns. It is difficult to collect in excavations for giant office buildings, but the material being removed has to be dumped somewhere, usually as fill. Ask the dump location from any driver as he waits for his truck to be loaded.

Subways and tunnels

Not many new subway lines or tunnels under bays, rivers, and congested areas are being built, but when they are, vast quantities of material have to be removed and dumped. This is also true where eastern and western mountains are being pierced by interstate highway tunnels. Sewer lines, cable trenches, pipelines

For some large-scale sewer projects, trenches twenty feet deep must be made, and sometimes even deeper cuts must be made for oil pipelines that run for hundreds of miles. Underground power lines and telephone lines, while not buried deeply, may still cause removal of weathered fossiliferous material. Even after the lines have been covered, a mound remains where rain may expose a few stray fossils. Ammonites have come from sewer construction in Colorado Springs. Tons of agatized coral and mollusks came from digging of a five-block-long sewer trench in Tampa, Florida. Texas pipelines rip through miles of Cretaceous fossil beds. Canals and dredging

The beautiful Silurian eurypterids, now in every major museum, were uncovered during construction of a canal at Lockport, New York, in the last century. Canal building and widening in Chicago cut through Silurian limestones containing trilobites, large cephalopods, and unique carbonized worms. Dredging almost anywhere in Florida is likely to unearth Pleistocene shark teeth, bones, and turtle shell plates along with the sand. Collectors stand at the discharge end of the dredge pipes and grab the dark-colored fossils as they fall in the wet sand. Dredging for ship channels throughout the Southeast and particularly in Florida has left little islands of dredged-up material often containing fossils. Any port city periodically dredges its harbors and may add new channels to its facilities. All are potential fossil-collecting grounds. City dumps

Old quarries make convenient dumps, and as the refuse rises in the quarry, prolific strata magically become available at waist level. Some dumps accept only clean fill, and some of this fill may be from excavations into fossil-bearing stone. A dump at Alden, New York, recently received a dozen truck loads of shale that turned out to be filled with trilobites. The shale had been removed from a basement excavation. Harbors and ballast dumps

Ships once carried rock as ballast in their holds. When they reached port, they would dump this in the harbor or along the shore if they were going to take back a full load. A ballast dump near a harbor, particularly along the East Coast, may contain foreign fossils. English ships often loaded up with flint, the type that weathers out of the chalk cliffs of Dover. Some of this flint has replaced ammonites and echinoids, making choice collector's items. Unfortunately, dumped ballast does not carry a label of origin, and it may be impossible to track down its fossils.

Dam construction

Large dams, such as those that have been constructed in recent years in the West and Southwest, are unmatched among major building projects for the quantity of rock they expose during construction. River cliffs are blasted back to the solid rock to give firm anchorage for the concrete wall that will dam the stream. This rubble may be dumped out of the way. Quarries are opened nearby to produce aggregate for the concrete of the dam. These may afford fine collecting. Even small dams will usually be cut into rock. Farmers who scoop out small stock tanks and ponds may also scoop out quantities of loose fossils. Peat bogs

Peat bogs are a rather rare and specialized type of collecting site limited to the northern glaciated states. Remnants of the last retreat of the ice, these bogs were death traps for Pleistocene animals. Mammoths and mastodons ventured in, became mired, and drowned in the black waters. The high acid content of the peat preserved bones and tusks and teeth. Whenever a peat bog is drained or dug out, there is a good chance of finding vertebrate fossils.

One such bog was scraped down to its clay bottom to make way for an expressway north of Chicago, and the rich peat was dumped on a farmer's field. The first rain washed out an accumulation of bones and teeth believed to be the remains of several complete mammoths. The farmer still plows up bones every spring and has a barn full of fine specimens.

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