Gravity measurements, free-air anomalies and GPS location data points from Santa Cruz and San Cristobal Islands in the Galapagos Archipelago

This data set includes the tied, raw gravity measurements and free-air gravity anomaly values collected using a LaCoste and Romberg model G type gravimeter during a 2012 survey of Santa Cruz Island and a 2016 survey of San Cristobal Island. Gravity measurements from the Santa Cruz survey were tied to a previous measurement at the Charles Darwin Station dock in Puerto Ayora (Ryland, 1971) and for the Santa Cristobal survey to a US Navy tie on a concrete pier in Baltra, Santa Cruz (0° 26' 3'' S, 90° 17' 1'' W). Latitude, longitude, and elevation were collected at each measurement location using a Trimble R7 GPS system. The raw gravity measurements were reduced to a Free Air Anomaly (FAA) by removing instrument drift (~0.01 mGal/day), the effect of elevation above sea level, and the WGS-84 reference ellipsoid. The data file is in ASCII format and was generated as part of the projects called Interdisciplinary Studies of the Galapagos Earth System, and Next Generation Imaging of Magmatic Processes beneath the Juan de Fuca Ridge using MCS data. Funding was provided by NSF awards OCE13-47731 and EAR11-45271.