Tuesday, November 24, 2009

THE DIAMOND MINE OF YELLOW CREEK


      "To the paleontologist there are few places in the world more interesting than the Diamond Mine at Linton," wrote Cleveland geologist John Strong Newberry in 1856, "since here he gets such a view of the life of the Carboniferous age as is afforded nowhere else, and of the great number of species found there."
      Few people other than men of science have heard of the Linton, Ohio to which Newberry referred, but it was a small village that once sprawled along the mouth of Yellow Creek.  No more  than a roadside park now sits at this historic site, and yet paleontologists still refer to it as Linton, and have excavated the hillside for fossils as recently as 2007.
      Linton was known primarily as the mouth of Yellow Creek prior to the 1800s when settlers erected a small blockhouse as protection from hostile Indians.  It remained an unincorporated village for more than a half-century, although a post office and a railroad depot put Linton upon maps by the mid-1850s.  This began the period when Connecticut entrepreneurs started operating the Diamond Mine, which produced a nine-foot seam of Freeport coal.  Below this rich seam, miners discovered a six-inch slate-like coal called canal from which they culled one of the richest pockets of fossils produced in the United States.
      Newberry and some of the most renowned paleontologists have visited the Diamond Mine, one such being Edward D. Cope, perhaps the most prominent paleontologist of the 19th Century.  His most notable contributions to science included the discovery of dozens of dinosaurs and the development of Cope's Law, which expounds upon the gradual enlargement of mammalian species.
     During the 150 years scientists have documented fossils gleaned from the Diamond Mine, ten dozen taxa of invertebrates, including small worms, millipedes and crustaceans, and forty taxa of vertebrates, mostly fish, have been documented.  According to Dr. Mark J. Camp in his book "Roadside Geology of Ohio," some fossils found at Linton are the only such kind ever discovered.
      "The Linton location ranks as the most prolific Pennsylvanian vertebrate fossil in the world," Camp wrote.
      Camp also stated that the most common fish found at Linton, numbering in the thousands, is the coelacanth, a carnivore that attained sizes of 6.5 feet in length and weighed nearly 198 pounds.  It was thought to have gone extinct with dinosaurs, but was discovered off the south coast of Africa in 1938.  A group of scientists theorize the coelacanth represented an early stage in the evolution of fish to terrestrial four-legged animals like amphibians.
      Long before the Ohio swept past what is now Linton, once sat an ox-box lake in which these fish including sharks and the coelacanth--as well as invertebrates inhabited.  A complex chemical process under enormous tonnage of sedimentary deposits preserved and fossilized these once living creatures in the canal seam of the Diamond Mine.
      The Diamond Mine officially operated from 1855 to 1921, collapsing during 1924.  In the ensuing years, scientists continued collecting specimens at dump sites of the mine and by the 1960s were taking them from the road cut nearby the development of the four-lane highway now consisting of Ohio Route Seven.  Scientific activity at the hillside cut discontinued during 2007.
      Many of the Linton fossils can be observed at numerous museums, including the Cleveland Museum of Natural History, the Orton Geological Museum of Ohio State University and the Smithstonian Museum of Natural History in Washington D.C.