I have a shapefile from Mexico´s INEGI site that doesn´t have a .prj file. I am having trouble defining the projection in ArcGIS. INEGI tells me it is projected as Lambert Conformal Conical with a ITRF92 GCS. From what I understand, this GCS should be the same as WGS84 (I have used this with other INEGI files and it matched). This combination of LCC & WGS84 doesn't exist in ESRI´s system, so I tried to create a custom projection coordinate system with the following information given by INEGI:
longitude of origin: -102.0,
latitude of origin: 12.0,
standard parallel 1: 17.5,
standard parallel 2: 29.5,
false easting: 2500000.0 m,
false northing: 0.0 m
But this doesn´t work - ArcGIS puts the file in Africa, not Mexico (though it seems to be the right scale).
I´m wondering if there is something going wrong with the GCS, for which INEGI gives this information:
Datum: ITRF92
Sphereoid: GRS80
Semimajor axis: 6378206.4
Inverse Flattening 294.9786982
These numbers are not the same as ESRI´s WGS84 or ITRF92, and I can´t figure out how to change them in the "Define Projection" tool.
This is the link to the site that contains the data: http://www.inegi.org.mx/geo/contenidos/recnat/edafologia/vectorial_serieii.aspx
At the bottom are the links to the date, I downloaded "Perfiles de Suelo".
The extent of the data is:
Top -2347872.613848
Bottom -340538.708859
Left -1075400.666415
Right - 4073175.438209
The data is supposed to cover the nation of Mexico.