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EPSG:4612 — JGD2000

JGD2000 — Japan's pre-2011 geodetic datum, retained for legacy mapping and pre-earthquake records.

Code
EPSG:4612
Type
Geographic 2D
Area
Japan

PROJ definition

+proj=longlat +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +no_defs +type=crs

Geographic bounds

W 122.38°   S 17.09°   E 157.65°   N 46.05°

Convert coordinates with EPSG:4612

Official EPSG transformations for JGD2000

Datum transformations involving EPSG:4612 published in the EPSG dataset, with parameters, accuracy and area of use:

About EPSG:4612

EPSG:4612 is the Japanese Geodetic Datum 2000 (JGD2000), aligned with ITRF94 at epoch 1997.0 on the GRS 80 ellipsoid. It replaced the historic Tokyo Datum (EPSG:4301) and was Japan's official datum from 2002 until JGD2011 superseded it after the Tōhoku earthquake. The 19 Plane Rectangular Coordinate System zones referenced to JGD2000 (EPSG:2443-2461) remain in widespread use for legacy datasets.

For any region affected by post-2011 crustal deformation — mainly eastern and northeastern Honshu — convert legacy JGD2000 records to JGD2011 using GSI's published grid before performing analysis or comparison with current surveys.

Common use cases

  • Pre-2011 Japanese cadastre and mapping
  • Legacy GIS datasets from Japanese ministries
  • Migrating historical aerial-photo control points

Common transformations from EPSG:4612

Frequently asked questions

Should I migrate JGD2000 data to JGD2011?
For records in regions affected by the 2011 earthquake, yes — use GSI's grid-based transformation. For regions outside the deformation field the difference is negligible.
What is the proj4 string for EPSG:4612?
The proj4 definition for EPSG:4612 is: +proj=longlat +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +no_defs +type=crs
Where is EPSG:4612 used?
EPSG:4612 (JGD2000) is defined for the area: Japan.