1. Simple Bouguer gravity anomaly map : Raleigh 30x60-minute quadrangle, 1996 Yale Public content 1996. 2008-10-23T13:23:44Z. 2016-07-23T21:11:02Z. Lawrence, David P. N.C. Dept. of Environment, Health and Natural Resources, N.C. Geological Survey, Division of Land Resources. English. text. Public. North Carolina and North Carolina.