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Lance Hodges has reported evidence indicating that the use of the term “reef” is inappropriate as applied to some ancient (Paleozoic level) facies in the Great Lakes region. A similar conclusion apparently applies to Mesozoic level “reefs” here in the northwest U.S.A. Orr and Orr in Handbook of Oregon Plant and Animal Fossils (1981, p 82) say: “The tendency in the geologic literature in the past has been to call rich accumulations of fossils ‘reefs’. More often than not what is called a bioherm (reef) is in fact a ‘biostrome’ or fossil rich lense without form or internal structure.” Two examples from early 20th century geologic literature (second and fourth decades) of stuctureless accumulations mislabeled reefs are then cited. The reef discussion’s concluding sentence states, “Although biostromes are not uncommon in the State [of Oregon] true bioherms or reefs are unknown.”

Please supply more identifying information on locales. It took this reader awhile to track down the Richvalley, Indiana, and Formosa, Ontario, sites on maps. For other curious readers, Richvalley, Indiana, is in north central Indiana (Wabash County) close to the Wabash River, approximately five miles west of the city of Wabash. Are we readers to infer that the “reef complex near Richvalley (Fig. 2, p 86) is part of “the classic Silurian reef at Wabash” (p 90)?

Richard Kutsch Florence, Oregon

Editor’s note:

The reef complex near Richvalley is not part of the classic Silurian reef at Wabash. Interested readers should contact Dr. Hodges regarding the specific locations of the various reefs. He can be contacted through the Geoscience Research Institute.

Incidentally, another classic “reef” appears to have succumbed to the scrutiny of additional investigation. The famous Steinplatte reef of the Austrian Alps, a classic upper Triassic reef, is now considered to be a “platform-edge sandpile.” See: Stanton RJ, Jr., Flügel E. 1988. Geological Society of America Abstracts with Programs 20(7):A201, #11494.