The Appalachian Fold and Thrust Belt: Tectonic Petrology of New York

New York was exposed to multiple collision events beginning about 1.1 bya. The second event occurred around 700 mya which split along rifts about 660 mya. These two older events were called the Grenville and Pannotian orogenesis. About 450 mya, island arc collisions resulted in the Taconic orogeny. The Acadian and Alleghenian orogenies followed during the Devonian time ending with the supercontinental assembly of Pangea. Pangea rifted apart starting about 220 mya lasting into Jurassic time.The Adirondack Mountains formed during the Grenville orogeny separated by the Carthage-Colton Mylonite Zone, a zone of tectonic brittle and ductile shearing produced by the Grenville tectonic compression.The Hudson Highlands and Manhattan Prong consist of rocks deposited prior to the Grenville uplift but were metamorphosed and deformed multiple times by ensuing uplift events including the Taconic, Acadian, and Alleghenian uplifts.Chapter 1 presents a summary of Eastern New York geology. Chapter 2 begins a discussion of the Adirondack Mountains. Chapter 3 presents the Hudson Highlands and Manhattan Prong collisional uplift. Chapter 4 summarizes the Hudson-Mohawk Lowlands and Taconic Mountains. Chapter 5 presents the Northern Lowlands and Tug Hill Plateau geology. Chapter 6 offers field evidence on the Carthage-Colton Mylonite Zone. Chapter 7 shifts back to the Northeastern Adirondack Mountains. Chapter 8 continues with dike intrusions of the Northeastern Adirondacks. Chapter 9 presents a brief geological summary of the Southern Lake Champlain Valley. Chapter 10 begins a discussion of the Hudson Highlands. Chapter 11 continues discussing Late Proterozoic shear zones of Western Hudson Highlands. Chapter 12 discusses Ottawan granitoids of the Western Hudson Highlands. Chapter 13 presents megaboudin shear structures along the leading edge of the Taconic Thrust Sheet. Chapter 14 presents Taconic Thrust obduction. Chapter 15 begins the discussion of New York City and the Manhattan Prong geology. Chapter 16 briefly summaizes Staten Island geology. Chapter 17 ends the book with paleotectonic history and the Taconic Frontal Thrust System epilogue. Read more