Stories in Stone Blog – Page 118

Cambrian Life in Wisconsin

As I have noted earlier in regard to the footprints in Mexico and the basalt in India, quarries often open up windows into stone that help geologists better understand the world. One of those revelatory quarries is found in Wisconsin, about 200 miles northwest of Milwaukee, where paleontologists found a beach-load of jellyfishes that died 510 million years ago. Each jellyfish resembles an aerial shot of a crater with a slightly raised center, the bell of a jellyfish, surrounded by a concave ring that ends in a prominent rim. The biggest are up to 70 centimeters in diameter.

Fossils from Wisconsin. Fossil D=70cm. From Geology Feb. 2002.

Fossil dealer Dan Damrow discovered the jellyfish in 1998 and four years later co-wrote an article (Geology, February 2002) describing the animals with paleontologist James Hagadorn. Technically known as medusae, the jellyfish were pelagic carnivores that moved into the littoral zone to hunt but a receding tide could trap the animals in great masses on the beach. As the tide ebbed and returned, fine-grained sediment covered the jellyfish, preserving the rarely preserved soft tissues. Ripple marks surround and in a few cases pass through the fossils. Damrow and Hagadorn report that the fossils were found in seven, flat-lying beds, which covered perhaps a million years of time, and that they provide new insights into the Cambrian.

The Krukowski family own the quarries and sell the fossiliferous rock under the trade names Highland Brown Antique, Sandy Creek and a sawn version called Cambrian Cream. Uses include architectural veneer stone, thin veneers, outcropping, steps, flagstone, and landscape retaining walls. The sawn version is transferred into countertop slabs, cladding, flooring and a variety of architectural and landscaping products. Because no one had recognized the fossils until the Damrow saw them, many people could have the fossils in their homes without knowing it.

Climactichnites (from Wikipedia)

Paleontologists have also found another unusual fossil at the Krukowski site. Known as Climactichnites, the fossils resemble tire tracks and have been described as both trace fossils and body impressions of a gelatinous zooplankter. More recently, a graduate student of Hagadorn’s has reexamined the traces from Wisconsin and other sites, and interpreted them as gastropod tracks, possibly from some of the earliest terrestrial animals. Apparently life in the Cambrian in what became Wisconsin was rather interesting.

Overlooked but not Forgotten

Many people, including me, have written extensively about the famous white limestone from Indiana. In my book Stories in Stone, I call the Salem Limestone, “America’s Building Stone,” and as far as I have been able to discover, it is the only building stone used in all 50 states. Recently, however, I have learned of another white limestone often mistakenly described as Salem. Much to my pleasure, being a native of Kentucky, that other stone hails from quarries in Warren County, Kentucky, in the southwest corner of the state.

The story of the Bowling Green Oolite comes from research by Western Kentucky University geologists Mike May and Ken Kuehn. They found that the oolitic limestone was popular from the 1870s to the 1920s with the quarries shutting down around 1937. During that time it became famous for its pure white color and received a gold medal at the World’s Columbian Exposition in Chicago in 1893 and the highest award at the Louisiana Purchase Exposition (St. Louis World’s Fair) in 1904. A 1923 Kentucky Geological Survey Publication, written I am sure without any bias, described the Bowling Green rock as “The Aristocrat of all the limestones.”

The publication further noted one unusual aspect of the stone—petroleum “impregnated” the rock. Oil gave the rock a dingy and unpleasant color when first quarried and carved, but soon the evaporation of the occluded petroleum left behind a stone of “great whiteness and remarkable beauty.” And it goes without saying that Bowling Green Oolite had superior strength and durability.

Episcopal Church of Saint Thomas (from St. Thomas web site)

Like the Salem, the Bowling Green Oolite, formally known as the Girkin Limestone, is Mississippian in age. The Girkin is most famous as the stone where the Mammoth Caves of Kentucky formed. The stone crossed state boundaries, with structures such as the U.S. Custom’s House in Nashville, TN and the Hall of Records in Brooklyn, NY; and religious boundaries, going into Methodist, Presbyterian, Catholic, and Episcopal churches, as well as a synagogue. One of the most famous buildings is the Episcopal Church of Saint Thomas in Manhattan, finished in 1913, during the prime years for usage of white limestone from the Midwest.

I suspect that most buildings that I think of as Salem Limestone are Salem, particularly in areas in the west, but I now know that some may have been mislabeled. I look forward to finding more buildings from my home state.