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I downloaded the data from here https://geo-nsdi.er.usgs.gov/metadata/map-mf/2323/metadata.faq.html

When I loaded it into QGIS it says it has no CRS set. There is no .prj file. After trying a variety of different CRSs I tried making my own custom CRS The string I came up with is.

+proj=lcc +lon_0=-117.3819444 +lat_0=23.0 +datum=NAD27 +units=m +no_defs +ellps=clrk66 +a=6378206.4 +lat_1=33.0

This is my first time trying to make a custom projection. The data is put in Canada north of where it should be. It should be in the Great Basin in the USA mostly in Nevada.

Here is the pertinent information I used to guess at the string.

Any ideas on what I can change to have it placed in the correct place?

What coordinate system is used to represent geographic features? The map projection used is Lambert Conformal Conic.

Projection parameters: Standard_Parallel: 33.0

Standard_Parallel: 45.0

Longitude_of_Central_Meridian: -118.0

Latitude_of_Projection_Origin: 23.0

False_Easting: 0

False_Northing: 0

Planar coordinates are encoded using Coordinate pair

Abscissae (x-coordinates) are specified to the nearest 130.0

Ordinates (y-coordinates) are specified to the nearest 130.0

Planar coordinates are specified in meters

The horizontal datum used is North American Datum of 1927.

The ellipsoid used is Clarke 1866.

The semi-major axis of the ellipsoid used is 6378206.4.

The flattening of the ellipsoid used is 1/294.98.

Vertical_Coordinate_System_Definition:

Altitude_System_Definition:

Altitude_Datum_Name: National Geodetic Vertical Datum of 1929

Altitude_Resolution: 30.0

Altitude_Distance_Units: meters

Altitude_Encoding_Method: Attribute values

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  • Change lon_0 to -118 and add lat_2=45.0 and see how that goes.
    – mkennedy
    Jul 27, 2020 at 15:56
  • That worked. Looking at the faq now I see the two standard parallels. For anyone interested I found the standard here proj.org/operations/projections/lcc.html. Jul 28, 2020 at 20:29
  • I don't need the points. If you add an answer, you can accept it after a day or so.
    – mkennedy
    Jul 29, 2020 at 3:02

1 Answer 1

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My final string is below.

+proj=lcc +lon_0=-118.0 +lat_0=23.0 +datum=NAD27 +units=m +no_defs +ellps=clrk66 +a=6378206.4 +lat_1=33.0 +lat_2=45.0

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