A loop in GSadjust refers to all of the data for which a single drift-correction is applied. Traditionally, loops consist of a series of station occupations that start and finish at the same station (e.g., A-B-C-D-E-A). In the context of GSadjust, a loop may actually comprise two loops in the field, e.g. A-B-C-D-E-A-B-C-D-E-A (this double-loop approach is often used in high-precision surveys). Or, stations in a GSadjust loop need not be visited in any particular order; the survey A-B-C-B-A-C-D-E-C-A could also be a defined as a single loop. Although often the same drift-correction method will be used throughout a campaign, the method could also vary by loop.
The following drift-correction methods are available:
