Line of Closure : A straight line, in a horizontal plane containing the last station of the survey, drawn from the projected surface location to the last station of the survey. (Bul D20)
The Mudblogger (Oilfield, Energy and Related Photographs), Oil Field Glossary, TX, USA 2014. http://mudblogger.com/oilfield-glossary/, (Oil - Amer) {777}