Footnotes
[1]Most of the information for this section was graciously supplied by Clara E. Follette, Librarian and Museum Director, Vermont Historical Society, Montpelier, Vermont, in a letter to the author dated April 26, 1961.
[2]“The governors (and other gentlemen) appear to have included Sir Henry Moore, Governor of New York, General Carleton, Governor of Quebec, Brig. General Philip Schuyler (and Adolphus Benzel, map maker). The activities of these persons on the lake at that time were evidently concerned with making observations, primarily to determine boundaries.”
[3]Seely, H. M., 1910, Preliminary Report of the Geology of Addison County; Vermont State Geologist, 7th Biennial Report, p. 257-315.
[4]Concretions consist of concentrations of certain chemical elements and compounds into regular or irregular masses. Many times the center of a concretion consists of a definite nucleus such as a grain of sand or shell fragment. For a general idea of the size and shape of the concretions seen along the Button Bay State Park beach see [Fig. 3] and [cover picture].
[5]These clays were deposited from marine waters which flooded the Champlain Valley after the final retreat of the glaciers which completely covered New England during the “Great Ice Age” or Pleistocene Epoch. The Pleistocene Epoch began approximately one million years ago and if the age of the Earth is considered to be five billion (5,000 million) years, then, the clays do record recent geologic history.
[6]As the weight of the ice was removed from the Hudson Valley region the earth’s crust, in way of adjustment to this removal of weight, slowly began to rise. Some geologists doubt whether the removal of ice weight alone can account for the crustal rise and propose other internal forces as partly or wholly responsible. The fact remains that the earth’s crust did rise in this area.
[7]As the ice retreated, a succession of lakes formed in the Champlain Valley. Each lake had a level waterline during its history and certain lakeshore features formed, as they do in any present-day lake, with respect to each past level water-line. For example, ridges of sand and gravel were heaped along the shoreline by lake waves. Wave-cut and wave-built flat areas or terraces were formed along the margins of lakes or along the sides of islands within a lake. Streams entering a lake built deltas by depositing materials it had carried down from the surrounding highlands.
[8]Elevation is measured in feet above the mean sea level of today, with mean sea level being zero feet.
[9]A most impressive view can be gained from any one of the several lookout points at the summit level of Mt. Philo. Looking to the west, toward Lake Champlain, and south in the direction of Vergennes and Button Bay State Park, a three dimensional view of an old lake (Lake Vermont) can be seen. In this view the present Lake Champlain Lowlands represent the old lake bottom and the numerous hills rising above this Lowland were once islands or near-islands which dotted the surface of the lake. It takes very little imagination to place yourself on the “island of Mt. Philo” and to visualize a boat tied to a dock just below the rocky cliffs on which you stand. A trip to Mt. Philo with its spectacular view of the Champlain Lowlands (see [Fig. 6]) is recommended.
[10]One word of caution, the Park authorities may import sand from other areas of Vermont to improve the swimming facilities along the beach. In this case, the abundant sand on the beach will not constitute the “natural beach composition” for Button Bay State Park.
[11]The blue color is due to the presence of ferrous iron (bivalent iron) together with iron compounds in which iron has its higher chemical valence (ferric iron). This ferrous iron demands a chemically reducing environment for its formation and indicates that the clays were deposited in a shallow sea or that they remained for some time beneath a stable water-table. They contained a fair quantity of decaying organic material.
[12]The brown color is due to the presence of the ferric hydroxide, goethite (HFeO₂).
[13]This fossil whale is scientifically known as Delphinapterus vermontanus (Thompson).
[14]The pelecypods found are scientifically known as Macoma groenlandica and Saxicava rugosa.
[15]The size limits of sand lie between 2mm in diameter (largest) and ¹/₁₆mm in diameter (smallest). Two millimeters (mm) equals approximately ²/₂₅ inches. Fine sand would fall between ¼mm and ⅛mm in diameter.
[16]Convolute beds show their layers thrown into a series of folds (some quite irregular) which result from the pressing weight of overlying sediments on highly plastic layers beneath. Some feel that these folds were the result of actual flowage of the layers in the direction of their tilt, and others credit the distorted bedding to the pressing weight of large boulders. These dragged across the layers while still frozen to overriding glacial ice.
[17]The author noted both Macoma groenlandica and Saxicava rugosa (see [Fig. 10] and [Plate 1], Sketches 3 and 4).
[18]Fossils are the preserved evidence of past life (animal or plant) as found in rocks or sediments, for example, the clams found in the clays. They may be direct evidence, such as the actual shells or mineralogically replaced shells of long-dead animals; or indirect evidence, such as the tracks or trails of animals now preserved in rocks.
[19]Geologic time is divided into four Eras which are designated from oldest to youngest: Precambrian, Paleozoic, Mesozoic, and Cenozoic. Each of these Eras is divided into geologic Periods of time. The Ordovician Period is next to the oldest Period of the Paleozoic Era. This Period began some 420 million years ago, and ended approximately 360 million years ago.
[20]Present Arthropods include the insects, spiders and crabs. Arthropods, which are invertebrate animals (without backbones), are characterized by jointed legs, chitinous outer covering and segmented body parts. Trilobites were very numerous in the early Paleozoic seas, but became extinct before the end of that Era.
[21]The folding and the faulting of the Ordovician rocks took place sometime between the closing phases of the Ordovician Period and the beginning of late Silurian time (between 360 and 330 million years ago). Usually these earth movements are ascribed to the Taconic Disturbance which took place at the end of the Ordovician Period.
[22]A walk along the beach in the direction of Button Island or “sickle point” (west and then south from the northern boundary of the Park) traverses the following geologic formations: the Glens Falls limestone which can be seen on Ship Point (actually an island off the northern end of the Park); the Orwell limestone, seen on Button Island; the Valcour formation which makes up “sickle point”; and the Crown Point limestone which is found on the Basin Harbor-side of “sickle point.” These rock units belong to the Chazyan Stage (Crown Point limestone and Valcour formation) and the next younger Mohawkian Stage (Orwell and Glens Falls limestones) of the Middle Ordovician Champlainian Series.