Help converting old WA grid reference coords...

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Have googled...no luck :( Does anyone know what old grid references from the early 1990's in WA mean and how to convert these to modern MGA??
For example: 14000N 8000E.
I have tried various calculators and they havent helped...To make matters worse, the old map isnt any help as it doesnt even say what type of grid reference or Geocentric datum was used!!
I can work it out roughly...but roughly isnt good enough :)
 
They look like UTM co ordinates
The other setting you will need is the zone . It will most likeley be 51j if your around the middle of the WA
here is a link to enable you to work it out
https://www.maptools.com/tutorials/grid_zone_detailsThere are many utm to long / lat converts online
Yeah they would be a UTM, however not MGA or GDA94. So even when I have been using the correct zone, it wont convert as says invalid. Usually UTM's contain more than 5 digits....
I just dont know what geocentric datum they are.....
 
Your map might be a 'local' map from a mining report or similar. If so and you find the report it came from, it should provide the context to allow you to work out the full UTM.
 
Your map might be a 'local' map from a mining report or similar. If so and you find the report it came from, it should provide the context to allow you to work out the full UTM.
Love your thinking!....But unfortunately the map is from an old WAMEX report and they dont mention what they have used :( They just refer to it as "true north and grid north"...Anyhow, have kinda done the more abstract thing and have managed to overlay the map into Google earth using landmarks as a surrogate guide and have sorta close coords :)
 
Have googled...no luck :( Does anyone know what old grid references from the early 1990's in WA mean and how to convert these to modern MGA??
For example: 14000N 8000E.
I have tried various calculators and they havent helped...To make matters worse, the old map isnt any help as it doesnt even say what type of grid reference or Geocentric datum was used!!
I can work it out roughly...but roughly isnt good enough :)
In your example there are numbers missing so it's impossible to say, but it is like you say, part of a grid reference.

on some maps there are a few different types of coordinates along the side and along the bottom of the map.

This for example
 

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In your example there are numbers missing so it's impossible to say, but it is like you say, part of a grid reference.

on some maps there are a few different types of coordinates along the side and along the bottom of the map.

This for example
Yeah thats MGA :) I understand MGA, but literally cant find what the Northings and Eastings referred to in some WA older reports and maps refers to. I read old WAMEX reports all the time and see this in many older reports, where they use this type of referencing. I think now after more study that they are likely grid references related to what ever grid the company is using or has created. Either way, thank God for landmarks as this is now my way of working out it out fairly closely!
 
Can you google earth an aerial of the WAMEXs map area of coverage and identify some features from that aerial? Google earth can give you the modern coordinates for those features and give an idea of the difference between the WAMEX coordinates and GPS coordinates.
This may allow you to just estimate an offset when in the field.
 
Can you google earth an aerial of the WAMEXs map area of coverage and identify some features from that aerial? Google earth can give you the modern coordinates for those features and give an idea of the difference between the WAMEX coordinates and GPS coordinates.
This may allow you to just estimate an offset when in the field.
yep thats what I am now doing. I can import a screenshot of the map into google earth and using landmarks that are on both such as wells, hills, fences etc, can get reasonably close. When I get a chance, I will venture out and see how accurate that is :) Just finished reading another WAMEX report and can now confirm that the coords they use are related to grids for exploration companies (such as "Austin grid"). Managed to find some of the actual grids in an older mining company report from 1981, so now have these :) Thats a start!
 
yep thats what I am now doing. I can import a screenshot of the map into google earth and using landmarks that are on both such as wells, hills, fences etc, can get reasonably close. When I get a chance, I will venture out and see how accurate that is :) Just finished reading another WAMEX report and can now confirm that the coords they use are related to grids for exploration companies (such as "Austin grid"). Managed to find some of the actual grids in an older mining company report from 1981, so now have these :) Thats a start!
Yes, we geos have always had to use that approach to convert local company coordinates to absolute coordinates. Keep in mind also that absolute coordinate systems have changed a couple of hundred metres since they became commonly used in 1966.
 
Yes, we geos have always had to use that approach to convert local company coordinates to absolute coordinates. Keep in mind also that absolute coordinate systems have changed a couple of hundred metres since they became commonly used in 1966.
MGA people!....MGA!!!! :)
 
Hi @kingswood When I used to work in the mining industry in the 90's we used to drop the leading parts of coordinates, so that it became more managable. when making hand crafted maps.

Especially when working in small areas.

Most coordinates on maps from the 90's (small area geological maps, open pit mapping, souil sampling etcs) where done in AMG coordinated.
The northings are a 7 digit number, and as all of the goldfields have a northing thats starts with a 6, usually this 6 is dropped.
The eastings are a 6 digit number.
So a coordinate of 599600, 3522000 Most likely is short hand for :

6599600, 3522000

Hope this helps
 
Hi @kingswood When I used to work in the mining industry in the 90's we used to drop the leading parts of coordinates, so that it became more managable. when making hand crafted maps.

Especially when working in small areas.

Most coordinates on maps from the 90's (small area geological maps, open pit mapping, souil sampling etcs) where done in AMG coordinated.
The northings are a 7 digit number, and as all of the goldfields have a northing thats starts with a 6, usually this 6 is dropped.
The eastings are a 6 digit number.
So a coordinate of 599600, 3522000 Most likely is short hand for :

6599600, 3522000

Hope this helps
Thanks for this :) I will check the maps and see! Very useful info as that may help with some other maps too!
 
For what it's worth, I know that 1994 was when a heap of the WA maps changed. Anything before 1994 was probably not WGS84, and to convert the old 1966 (called officially the AGD66) system to WGS84 you have to add 140 metres to each of your easting and northing coordinates.
 
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