Report of a geological survey of Wisconsin, Iowa, and Minnesota - and incidentally of a portion of Nebraska Territory - made under instructions from the United States Treasury Department (1852) (14748390021)

Identifier: reportofgeologic00owen (find matches)
Title: Report of a geological survey of Wisconsin, Iowa, and Minnesota : and incidentally of a portion of Nebraska Territory : made under instructions from the United States Treasury Department
Year: 1852 (1850s)
Authors: Owen, David Dale, 1807-1860 Leidy, Joseph, 1823-1891 Norwood, Joseph Granville. 1807-1895 Parry, Charles Christopher. 1823-1890 Pratten, Henry Shumard, B. F. (Benjamin Franklin), 1820-1869 Whittlesey, Charles, 1808-1886 Dwight, Jonathan, 1858-1929, former owner. DSI Tucker, Marcia Brady, former owner. DSI Dawson, H. B., former owner. DSI Dall, William Healey, 1845-1927, former owner. DSI United States. General Land Office United States. Department of the Treasury
Subjects: Geology Paleontology Botany Botany Plants Plants Birds Birds
Publisher: Philadelphia : Lippincott, Grambo & Co.
Contributing Library: Smithsonian Libraries
Digitizing Sponsor: Biodiversity Heritage Library



Text Appearing Before Image:
The contrast in thickness in the two formations is equally remarkable. Nowherein Iowa have I found an exposed connected section of these limestones measuring * The sandstones which sometimes lie in close proximity to the limestones here spoken of, appear tobe of carboniferous date. 78 LIMESTONES OF RED CEDAR, more than sixty or seventy feet; while the depth of the Old Red Sandstone of GreatBritain is said, at certain localities, to equal the elevation of Mount Etna above thesea, reaching from ten to eleven thousand feet. Its average thickness, in theBritish Islands, is laid down, by some authors, at about half that amount. In the northern part of Iowa these limestones are seldom seen, by reason of theextensive drift, except in the deep cuts of the streams, and then only in low muralexposures, an example of which is shown in the middle ground of this landscape,looking over the extensive prairies in the Valley of Shell Rock, one of the easternbranches of the head waters of Cedar River.
Text Appearing After Image:
LIMESTONES OF SHELL ROCK, CEDAE VALLEY. SECTION II. ITS PALAEONTOLOGY. Pal/Eontologically, the limestones of this period, in Cedar and Iowa Valleys,may be divided into 1. Lower coralline beds; 2. Shell beds; and 3. Upper coralloid limestone. The beds containing the greatest abundance of Brachiopodes being included be-tween beds charged with fossil corals: of which coral beds the lower is so complete IOWA, AND WAPSINONOX RIVERS. 79 a mass of agglutinated remains of Polypi/era, that it may be almost considered apetrified coral reef; while the upper, though not presenting so great a variety ofspecies, and at first view hardly recognisable except as a white, close-textured lime-stone, is shown, under the magnifier, to be made up almost entirely of a fossil coral,closely allied to the genus Stromatopora, the concentric growths of which are sominutely compact, as seldom to be detected by the naked eye. To thill an excep-tion must be noticed, in some of the layers immediately superimposed on