REGIONAL GRAVITY MAPPING IN NEW YORK STATE

A total of 17,027 gravity measurements have been made in New York and Pennsylvania from 1966 to present. The data set covers 7° of longitude and 5° of latitude characterized by a spacing of about four kilometers. A network of base stations was established primarily by looping as explained in Nettleton. The bases were tied to the existing network of Innes and drift curves were constructed from base readings made at different times of day. The Simple Bouguer Anomaly (SBA) was computed by making corrections for latitude, free air affect, Bouguer and terrain corrections. The Simple Bouguer Anomalies were used to construct gravity maps of the surveyed area.

The gravity measurements were compiled to construct a regional gravity map of New York and Pennsylvania and larger scale maps of selected areas. Larger scale maps were constructed of Western New York, Tug Hill Plateau, Northern New York, Adirondacks, and Champlain Valley and eastern Pennsylvania. These gravity maps reveal gravity anomalies related to geology in each area. The most interesting anomalies are a north-trending series of gravity highs adjacent to a gravity low in western New York, a gravity low over the Tug Hill plateau possibly related to the uplift of the plateau and gravity anomalies related to abandoned gas fields. In Northern New York, a series of gravity highs are related to the Northern New York-Western Quebec Seismic Zone and in the Champlain Valley gravity highs are related to faulting and a buried pluton. In the Adirondacks, a gravity low is located over the anorthosite massif. The most interesting feature is the Scranton Gravity High in eastern New York and Pennsylvania which has an unknown region.