Seismic Refraction Study of a Portion of the Newark
Basin, Rutgers University, Busch Campus, Piscataway, New Jersey
Abstract--The Newark basin is an early Mesozoic extensional basin.
This particular study was undertaken in the Triassic Passaic Formation
in Piscataway, New Jersey. The Passaic Formation in this area contains
orthogonal fracture sets that strike NE-SW and NW-SE. The dominant set
of fractures strikes NE-SW. Azimuthal seismic refraction profiles showed
that faster compressional wave velocities propagate along orientations
with a higher number of fractures. Velocities of approximately 3.2-3.4
km/s were recorded along orientations than ran subparallel to the strike
of the dominant fracture set. Along the sub-dominant fracture set, which
is normal to the dominant set, velocities of 2.8-3.0 km/s were recorded.
[This slower velocity is attributed to ray paths crossing a larger number
of fluid-filled fractures.]