The New York State Survey, begun in 1836, was continued by James Hall from 1843 to 1898. During this time he was also state geologist of Iowa (1855–1858) and Michigan (1862). Since 1898, John M. Clarke has ably continued the Geological Survey of New York, the state which continues to be, in science and more especially in geology and paleontology, the foremost in America.
Western Extension of the New York system.—Before Hall finished his final report, we find him in 1841 on “a tour of exploration through the states of Ohio, Indiana, Illinois, a part of Michigan, Kentucky, and Missouri, and the territories of Iowa and Wisconsin.” This tour is described in the Journal (42, 51, 1842) under the caption “Notes upon the Geology of the Western States.” His object was to ascertain how far the New York system as the standard of reference “was applicable in the western extension of the series.” In a general way he was very successful in extending the system to the Mississippi River, and he clearly saw “a great diminution, first of sandy matter, and next of shale, as we go westward, and in the whole, a great increase of calcareous matter in the same direction.” He also clearly noted the warped nature of the strata, the “anticlinal axis,” since known as the Cincinnati and Wabash uplifts and the Ozark dome.
Hall, however, fell into a number of flagrant errors because of a too great reliance on lithologic correlation and supposedly similar sequence. For instance, the Coal Measures of Pennsylvania were said to directly overlap the Chemung group of southern New York, and now he finds the same condition in Ohio, Indiana, and Illinois, failing to see that in most places between the top of the New York system and the Coal Measures lay the extensive Mississippian series, one that he generally confounded with the Chemung, or included in the “Carboniferous group.” He states that the Portage of New York is the same as the Waverly of Ohio, and at Louisville the Middle Devonian waterlime is correlated with the similar rock of the New York Silurian. Hall was especially desirous of fixing the horizon of the Middle Ordovician lead-bearing rocks of Illinois, Wisconsin, and Iowa, but unfortunately correlated them with the Niagaran, while the Middle Devonian about Columbus, Ohio, and Louisville, Kentucky, he referred to the same horizon. The Galena-Niagaran error was corrected in 1855, but the Devonian and Mississippian ones remained unadjusted for a long time, and in Iowa until toward the close of the nineteenth century.
| The Geological Column of the New York Geologists of 1842–1843, according to W. W. Mather 1842. | ||
|---|---|---|
| Quaternary system | Alluvial division. | |
| Quaternary division. | ||
| Drift division. | ||
| Tertiary system | These strata are included in the next lower division. | |
| Upper Secondary system | Long Island division. Equals the Tertiary and Cretaceous marls, sands, and clays of the coastal plain of New Jersey. | New Red system of Emmons and Hall. |
| Trappean division. The Palisades | ||
| Red Sandstone division. | ||
Coal system of Mather, and Carboniferous system of Hall.
Old Red system of Catskill Mountains of Emmons; Catskill division of Mather and Hall; and Catskill group of Vanuxem.
| According to Hall 1843, and essentially Vanuxem 1842. | |
|---|---|
| Erie division [Devonian] | Chemung, Portage or Nunda (divided into Cashaqua, Gardeau, Portage), Genesee, Tully, Hamilton (divided into Ludlowville; Encrinal, Moscow), and Marcellus. |
| Helderberg series [Devonian-Silurian] | Corniferous, Onondaga, Schoharie, Cauda-alli, Oriskany, Upper Pentamerus, Encrinal, Delthyris, Pentamerus, Waterlime, Onondaga salt group. |
| Ontario division [Silurian] | Niagara, Clinton, and Medina. |
| Champlain division [Silurian-Ordovician-Upper Cambrian] | Oneida or Shawangunk, Grey sandstone, Hudson River group, Utica, Trenton, Black River including Birdseye and Chazy, Calciferous sandrock, and Potsdam. |
| According to Emmons 1842, Mather 1843, Vanuxem 1842, Hall 1843. | |
|---|---|
| Taconic System [Ordovician and Lower Cambrian] | Granular quartz, Stockbridge limestone, Magnesian slate, and Taconic slate. |
| Primary or Hypogene system | Metamorphic and Primary rocks. |
Correlations with Europe.—The first effort toward correlating the New York system with those of Europe was made by Conrad in his Notes on American Geology in 1839 (35, 243). Here he compares it on faunal grounds with the Silurian system. A more sustained effort was that of Hall in 1843 (45, 157), when he said that the Silurian of Murchison was equal to the New York system and embraced the Cambrian, Silurian, and Devonian, which he considered as forming but one system. Hall in 1844 and Conrad earlier were erroneously regarding the Middle Devonian of New York (Hamilton) as “an equivalent of the Ludlow rocks of Mr. Murchison” (47, 118, 1844).
In 1846 E. P. De Verneuil spent the summer in America with a view to correlating the formations of the New York system with those of Europe. At this time he had had a wide field experience in France, Germany, and Russia, was president of the Geological Society of France, and “virtually the representative of European geology” (2, 153, 1846). Hall says, “No other person could have presented so clear and perfect a coup d’oeil.” De Verneuil’s results were translated by Hall and with his own comments were published in the Journal in 1848 and 1849 under the title “On the Parallelism of the Paleozoic Deposits of North America with those of Europe.” De Verneuil was especially struck with the complete development of American Paleozoic deposits and said it was the best anywhere. On the other hand, he did not agree with the detailed arrangement of the formations in the various divisions of the New York system, and Hall admitted altogether too readily that the terms were proposed “as a matter of concession, and it is to be regretted that such an artificial classification was adopted.” De Verneuil’s correlations are as follows: