MAZE CAVES AS VERIFICATION OF POST-GLACIAL CAVE ORIGIN MODEL IN THE GLACIATED KARST OF NEW YORK

Caves in glaciated regions were originally thought to be predominantly post-glacial in age. Work from the 1970s through today showed survival of pre-glacial cave systems in these regions via agreement with pre-glacial dendritic drainage and base levels, presence of passages of large cross-sectional area, sequences of glacially derived sediment, and U/Th age dates from speleothems. This work focused on large cave systems of pre-glacial origin, and does not discuss post-glacial caves, only small tributary passages thought to be post-glacial.

A model proposed in the 1980s hypothesized agreement with glacial landforms and post-glacial deranged drainage as a method to determine post-glacial origins of certain caves, though no fieldwork was performed in glaciated regions to demonstrate this model. Fieldwork for this study performed at Hannacroix Maze in Albany Co., NY verifies this model through mapping of glacial landforms, combined with flow accumulations calculated from LiDAR data. Floodwater origins of Hannacroix Maze controlled by a swamp located in a depression aligned with ice flow direction of the last glaciation, as well as dye tracing demonstrating a connection of this cave to post-glacial deranged drainage verifies the model and demonstrates a post-glacial origin of this cave, and the hydrologically connected Merritts Cave.

Other maze caves in glaciated areas of New York are hypothesized to be post-glacial in origin, due to joint expression from glacial unloading combined with the shallow nature of epigenic maze caves making them vulnerable to glacial removal. Accurate passage cross-sectional area measurements obtained with laser rangefinder of New York maze caves combined with ranges of wall-retreat rates demonstrate formation times in agreement with glacial retreat dates of the Wisconsinan glaciation, including large maze caves such as the Glen Park Labyrinth. These maze caves mainly exist within the current deranged drainage, though smaller relict maze caves are not completely congruent with current drainage. These are at higher elevation from current streams and may have formed during higher water conditions such as during glacial retreat from melt-water. All maze caves visited were shallow (contained within 10 meters of the surface); making it likely future glaciations would remove these caves.