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I'm trying to map road accidents in Australia, which comes with x and y coordinates (e.g., x = 1328459.1 and y = 1670878 for Adelaide) as well as the following information:

PROJECTION LAMBERT
UNITS METERS
DATUM GDA94 SEVEN /* GDA94 SPHEROID GRS80 PARAMETERS
-28 00 00 /* 1st standard parallel
-36 00 00 /* 2nd standard parallel
135 00 00 /* Central meridian
-32 00 00 /* Latitude of projections origin
1000000 /* False easting (meters)
2000000 /* False northin (meters)
END

Using R and this list, I tried to translate it as follows

# Projection for accident coordinates (EPSG:3112)
proj <- "+proj=lcc +lat_1=-28 +lat_2=-36 +lat_0=-32 +lon_0=135 +init=epsg:3112 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs"

# Code spatial points
points <- proj4::project(accidents[, c("ACCLOC_X", "ACCLOC_Y")], proj = proj, inverse = TRUE)
accidents$longitude <- points$x
accidents$latitude <- points$y
names(accidents)[names(accidents) == "longitude"] <- "LONG"
names(accidents)[names(accidents) == "latitude"] <- "LAT

before mapping, but my approach appears to be incorrect given the resulting ggplot2-map (shapefiles were obtained from Natural Earth and subsetted to Australia):

enter image description here

Does anyone have an idea where the error is?

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PROJECTION LAMBERT
UNITS METERS
DATUM GDA94 SEVEN /* GDA94 SPHEROID GRS80 PARAMETERS
-28 00 00 /* 1st standard parallel
-36 00 00 /* 2nd standard parallel
135 00 00 /* Central meridian
-32 00 00 /* Latitude of projections origin
1000000 /* False easting (meters)
2000000 /* False northin (meters)
END

should be EPSG:3107 - GDA94 / SA Lambert. This is its Proj4 string:

+proj=lcc +lat_1=-28 +lat_2=-36 +lat_0=-32 +lon_0=135 +x_0=1000000 +y_0=2000000 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs 
  • Is there a way to convert it in QGIS ? – Duffer Mar 20 at 23:11

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