Geology of Hallock State Park Preserve–Presentation & Hike

This presentation and three-mile walk will examine the geology of the uplands and beach at Hallock State Park Preserve. We will focus on how the geologic development of the North Shore of Long Island and Long Island Sound, along with present-day coastal processes and groundwater flow, relate to the geology and biological environment of the Park. The geologic history of this area included continental glaciation that created the hilly moraines and flatter outwash plains of Long Island, followed by warming, consequent retreat of the ice front, development of a freshwater lake in Long Island Sound, sea level rise, and eventual filling of Long Island Sound by salt water. On the uplands, we will take a look at the soil, consider its origin and relationship to the vegetation, and visit an overlook at Hallock Pond, which is perched well above the main water table due to underlying clay. We will also observe the effects of human activity, such as sand and gravel mining. On the beach, we will consider the geologic origin of the various types of rocks, the role of waves and wind in shaping the beach, and how exposed layers of sand, gravel, and clay interact with groundwater and meteorological phenomena to create the hoodoo style of erosional topography on the coastal bluffs.