Brittle Faults of the Queens Tunnel Complex, NYC Water Tunnel #3

Mapping indicates that five generations of superposed brittle faults cut highly sheared granulite facies orthogneiss and associated rocks of the Queens Tunnel Complex. Faults in the Queens Tunnel vary from early ductile faults and related structures, to intermediate age steep to low angle normal and reverse ductile/brittle faults (often found injected by syntectonic granitoids) and subhorizontal brittle fractures, to steep, late-stage brittle faults with thick clayand zeolite-rich gouge zones and quartz veins.