EPSG:4261 — Merchich
Merchich (EPSG:4261) — a Geographic (degrees) system on the clrk80ign datum, used in Morocco. Parameters, proj4, WKT, accuracy ±0.1 m, plus a free converter to WGS84 and…
At a glance
- EPSG
- 4261
- Name
- Merchich
- Kind
- Geographic (degrees)
- Family
- Geographic (longitude/latitude)
- Ellipsoid
- clrk80ign
- Accuracy
- ±0.1 m (vs PROJ)
- Countries
- Morocco
Area of use
| West | -17.16° |
| South | 20.71° |
| East | -1.01° |
| North | 35.97° |
Projection parameters
| Projection | longlat |
| Ellipsoid | clrk80ign |
| Helmert shift to WGS84 | 31,146,47,0,0,0,0 |
+proj=longlat +ellps=clrk80ign +no_defs +towgs84=31,146,47,0,0,0,0
GEOGCS["GCS_Merchich",DATUM["D_Clarke_1880_IGN",SPHEROID["Clarke_1880_IGN",6378249.2,293.4660212936269],TOWGS84[31,146,47,0,0,0,0]],PRIMEM["Greenwich",0],UNIT["Degree",0.0174532925199433],AUTHORITY["EPSG","4261"]]
Sample conversion
Morocco capital: WGS84 -6.84160, 34.02090 → EPSG:4261 -6.8432095, 34.0235351
Values are within ±0.1 m at the test point.
About the Geographic (longitude/latitude) family
Merchich is a geographic coordinate system: positions are longitude and latitude in degrees on its reference ellipsoid, not metres on a plane. It is the datum layer that projected grids (UTM, national belts) are built upon.
Because it is unprojected, distances and areas cannot be measured directly from its degrees — convert to a metric projected system (or use a geodesic calculation) first. This page's converter does exactly that.
Related systems
- EPSG:26191 — Merchich / Nord Maroc
- EPSG:26192 — Merchich / Sud Maroc
- EPSG:26193 — Merchich / Sud Maroc (deg)
- EPSG:26194 — Merchich / Sahara Sud
- EPSG:26195 — Merchich / Sahara Sud
- EPSG:32628 — WGS 84 / UTM zone 28N
- EPSG:32629 — WGS 84 / UTM zone 29N
- EPSG:32630 — WGS 84 / UTM zone 30N
Useful links: Converter · Batch converter · File converter · Country page
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FAQ
- What is EPSG:4261?
- It is the coordinate system “Merchich”, a Geographic (degrees) system in the Geographic (longitude/latitude) family, identified worldwide by the code EPSG:4261.
- What datum does it use, and how accurate is it?
- It is based on the clrk80ign ellipsoid and it carries Helmert parameters to WGS84. The residual at the test point is about ±0.1 m versus PROJ; for centimetre work use a geodetic adjustment service.
- Where is this system used?
- It is used in Morocco. This page shows its area of use as a coordinate rectangle above.
- How do I convert EPSG:4261 to WGS84?
- Use the free coordinate converter above (preloaded with this system) to convert to WGS84, UTM, or any other system, within a ±0.1 m residual.
You may also need: Arab-world coordinate converter · Surveying file format converter · Batch coordinate file converter