This page summarises the main characteristics of the network.
Purpose
To enable the link between official geodetic and vertical datums and international reference systems to be determined and monitored.
Density
At least one geodetic datum reference mark (GDRM) on the stable part of each tectonic plate (Pacific, Australian, Antarctic)
Vertical datum reference mark (VDRM) to be co-located with each GDRM
Accuracy
Order: 0
Tier: Horiz A (0.05 m), Vert A (0.05 m)
Class: Horiz II (0.003 m, 3x10-8m/m), Vert II (0.003 m, 3x10-8m/m)
Class evaluation radius: all NRF marks
Mark characteristics
GDRM normally continuous GNSS
VDRM normally absolute gravity
May co-locate with other observation systems (VLBI, DORIS)
Location
To enable GNSS collection (GDRM)
To enable absolute gravity collection (VDRM)
Mark access
Data available from LINZ website
No physical access to mark