[R-sig-Geo] Datum/CRS for the worldHires map data

[Karl Ove Hufthammer]

Dear list users

I frequently use, and rather like, the worldHires map in 'mapdata'. The 
resolution is quite good (compared to the 'world' map).

However, by overlaying some data on a worldHires map (at around long = 
25.7 and lat = 70.9) I discovered that the map was quite inaccurate. The 
actual shape of the shorelines are quite good, but they are displaced 
(compare the maps with the maps in Google Earth and the shoreline data 
at http://rimmer.ngdc.noaa.gov/mgg/coast/getcoast.html).

The reason is obviously that the worldHires map is not in the WGS 84 
datum (which is reasonable, considering the age of the data). But which 
datum is it in? I could find no information on this in the helpfile, or 
on the referenced Web page? Does anybody on this list know, and perhaps 
have a ready-made CRS strings I can use to project it?

Also, does there exist any other R map packages with maps of this 
resolution (plain shoreline data without any additional metadata would 
be OK), preferably with the maps actually included in the package, and 
not downloading them from the Internet on demand?

-- 
Karl Ove Hufthammer