Evaluation of the NAVD 88 Using Aerogravity and Lidar Data in the Gulf of Mexico

Problems in the current gravity database:

•Tidal systems differ between NGS (tide-free) and NIMA-proprietary (mean tide) data •Data reference NAD27 & NGVD29 but can be converted to NAD83 & NAVD88 •Data collected for a long time period (dating back more than 80 years), may contain local or regional biases •Effect of subsidence and the Earth’s crustal movement on gravity has become considerable

•Data gaps in near shore and difficulty-to-access areas