1:100,000 topographical maps

You were definitely right about the price and date of survey of the maps. I guess Ill have to narrow down the places I require a 1:1000000 map for. $100 minimum order on cd seems a bit expensive when compatred to 250,000 series.

thanks

Hey guys

Thanks for the feedback, I was thinking this may be the case, however was hopeful. Thanks for all the feedback and responses.

regards

Elmo

Davoe
"they were last done over 20 years ago" - not true - From Geoscience Australia website - Currency: Ranges from 1961 to 2000, Forward Program: Selected maps under revision....so while some maps are over 40years old, some are probably only a few years old, if that.

"the 250k maps are better as they are generally around 5 years old" - close enough - Currency: Ranges from 1967 to 2002. 95% of maps have a reliability date of 1994 or later. Also depends what you mean by "better". Old maps are sometimes good for certian applications. eg finding old tracks/bores no longer mapped.

"same detail just smaller scale" - not true - for example 250K maps have 50m contours, 100k maps have 20m contours. Areas of more subtle topography will not be evident on 250K maps. Depends on your application if this is of any use....so depsite all that I have pointed out 250K maps may be the best option for some.

Cheers
Greg

Explorer just to clarify why i made that coment I probably made a toosweeping judgement. My experience with the maps are from working for the Geological survey in the goldfields in this region most 250k maps are around 2000 and most 100k are around 1983. There are no useable tracks on the 100k sheets that are not on the 250k and most tracks 98% on the 100k are on both but alot of tracks are a straight copy from one to another and are no longer useable and alot are totally gone (it only takes a fire and the track is totally gone for good). as it was our job to totally trverse the 100k sheets you get a good idea of what tracks exist still and which ones dont

oh and dont get the topo maps mixed up with geoscience maps they are 2 different things 100k geol survey maps are being undertaken currently as the 250k geol mapsw were done around late 60s - geol survey maps can have more updated tracks/deleted tracks if done by the geo but have no topography

Davoe - I understand your interpretation - for example I have the Peak Charles 100K map and it is simply a blown up section of the 250K map (apart from the extra contour detail). In these remoter areas there is no other tracks present so they can of course not be shown. A different story in the south west where extra tracks appear on the 100k maps (though a tad out of date on some) for example.

"oh and dont get the topo maps mixed up with geoscience maps they are 2 different things" - yes I know - I have both 250k topo and Geology sets on CD and a few of the 100k Geology and topo ones as well (paper)...not to mention some 50k geology, 50K topo (SWWA series of which I sell on CD..Kimberley coming soon), 25k topo and a load of other scales...and one or two air photos.......

Greg
Exploration Geologist/Environmental Scientist

Thanks Davoe, The Explorer and Geoff/Karen for the posting/s. Only thinking about the 100,000 scale for a bit of hunting in the Cape York/ Gulf Area. Already use Oziexplorer with the 250,000 scale maps. Will continue to stick with this series of maps as like everybody has suggested, they are newer and thus a lot more accurate.

Thanks All