The Shed Brook Discontinuity in the western Mohawk Valley region of central New York is an unconformity separating lacustrine beds of the Valley Heads drift (Port Bruce stade) from pre–Valley Heads lacustrine deposits (Nissouri stade). The Little Falls Gravel is a fluvial unit that can be found draped by Valley Heads lacustrine deposits in the Mohawk Valley. The discontinuity and gravel represent subaerial erosion and braided river deposition in response to initial late Wisconsinan ice recession and lake drainage in the Mohawk Valley. These events were followed by Valley Heads lake impoundment and glacial readvances. The Shed Brook Discontinuity and Little Falls Gravel have a 14 C age constrained to 17–14.1 ka on the basis of stratigraphic relationships in central New York and the correlation of paleomagnetic declination records from central New York and the 14 C-calibrated New England varve chronology. The Shed Brook Discontinuity and Little Falls Gravel appear to be features equivalent in age to the Erie interstade (about 14.5–16 ka), an interval during which eastward drainage to the Mohawk Valley has been inferred for lakes in the Erie basin. Evidence for a river in the Mohawk Valley (Little Falls Gravel) indicates that it may have served as an eastern outlet for the Erie and Ontario basins, and thus allowed the first eastward diversion of meltwater away from the Mississippi Valley during the last deglaciation. Drainage down the Mohawk Valley entered Lake Albany in the Hud

The ecologic and stratigraphic development of the lower Hudson River estuary during late Pleistocene time was reconstructed from foraminifers and pollen in cores taken from Peekskill, New York, to The Narrows of New York Bay. Sediments deposited in freshwater, brackish water, and marine environments were penetrated by the cores, which ranged from 32.0 to 72.7 m. The foraminifers identified in the cores are divided into four assemblages, each characteristic of a local stratigraphic zone and biotope. Three of the assemblages currently thrive in the estuary; the fourth, composed primarily of benthonic foraminifers, is now found on the nearshore continental shelf from Portsmouth, New Hampshire, to Cape Hatteras, North Carolina, and in easternmost Long Island Sound. Spruce-fir, pine, and oak pollen assemblages occur in the cores and are zoned using the standard pollen zones established for the northeastern United States. The pollen zones are used for chrono-stratigraphic purposes. Following the dissipation of glacial Lake Hudson, tidal conditions were established in the estuary well before 12,000 yr ago. Estuarine conditions with salinities high enough to support foraminifers became established by ∼11,500 yr ago. About 10,000 yr B.P., salinity decreased slightly but was re-established by 9,000 yr ago. The maximum transgression of mesohaline brackish water into the estuary occurred about 6,500 yr B.P., as shown by the first appearance of foraminifers in the northern part of the are

Introduction A recent examination of the Hudson-Schroon valleys of the southeastern Adirondack region has furnished evidence that a remarkable, long, narrow glacial lake, with branching arms, lay in those valleys during the waning of the last great ice-sheet in northern New York. Before the former existence of this extensive body of water was known, more or less evidence for the former existence of certain local portions of the lake was presented in a numbr of publications. Ogilvie in 1902[1][1] and again in 1905[2][2] and Kemp in 1910,[3][3] briefly referred to lake terraces in the valley of the Schroon River, in the Paradox Lake and Elizabethtown quadrangles respectively. Next was a brief description of Glacial Lake Warrensburg by the writer in 1911,[4][4] the lake phenomena being wonderfully exhibited in the vicinity of Warrensburg. In 1914[5][5] the writer again described this lake. Another body of water, then thought to have been independent . . . [1]: #fn-1 [2]: #fn-2 [3]: #fn-3 [4]: #fn-4 [5]: #fn-5

The Hudson River is a 315-mile (507 km) river that flows from north to south largely through eastern New York state. It originates in the Adirondack Mountains at Henderson Lake in the town of Newcomb, and flows south to New York Bay, a tidal estuary between New York City and Jersey City, before draining into the Atlantic Ocean. The river marks out the eastern border between the U.S. states of New The Hudson is sometimes called, in geological terms, a drowned river. The rising sea levels after the retreat of the Wisconsin glaciation, the most recent ice age, have resulted in a marine incursion that drowned the coastal plain and brought salt water well above the mouth of the river. The deeply eroded old riverbed beyond the current shoreline, Hudson Canyon, is a rich fishing area. The former riverbed is clearly delineated beneath the waters of the Atlantic Ocean, extending to the edge of the continental shelf. As a result of the glaciation and the rising sea levels, the lower half of the river is now a tidal estuary that occupies the Hudson Fjord. Along the river, the Palisades are of metamorphic basalt, or diabases, the Highlands are primarily granite and gneiss with intrusions, and from Beacon to Albany, shales and limestones, or mainly sedimentary rock. The Narrows were most likely formed about 6,000 years ago at the end of the last ice age. Previously, Staten Island and Long Island were connected, preventing the Hudson River from terminating via the Narrows. At that time, the Hudson River emptied into the Atlantic Ocean through a more westerly course through parts of present-day northern New Jersey, along the eastern side of the Watchung Mountains to Bound Brook, New Jersey and then on into the Atlantic Ocean via Raritan Bay. A buildup of water in the Upper New York Bay eventually allowed the Hudson River to break through previous land mass that was connecting Staten Island and Brooklyn to form the Narrows as it exists today. This allowed the Hudson River to find a shorter route to the Atlantic Ocean via its present course between New Jersey and New York City. Suspended sediments, mainly consisting of clays eroded from glacial deposits and organic particles, can be found in abundance in the river. The Hudson has a relatively short history of erosion, so it does not have a large depositional plain near its mouth. This lack of significant deposits near the river mouth differs from most other American estuaries. Around New York Harbor, sediment also flows into the estuary from the ocean when the current is flowing north. The Hudson River valley also proved…