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Hi all, I've been putting together a couple of files for funsies (don't even have a gold detector at the moment!) over the last few nights regarding the Heathcote goldfield, and I figure that it could be useful for others. I've created separate files for both reef lines and alluvial / surfacing based on the relatively recent 1m resolution Lidar data that's publicly available. Attached is a zip with those files in both Google KML format and geopackage for QGIS. Some notes:
* The usual, these files don't imply prospecting access to the ground covered, please check if you're allowed to prospect in any given spot before you head out.
* Pretty much all the decent hard-rock mines (and anything that to my eye looked like a linear row of shafts or pits) are there, the line is named if known but the state of putting names to mines at Heathcote is a dog's breakfast at the moment by the looks. Both the department maps and Geovic are woeful. I'm interested in the history so I'll be looking to update the file with more names when I can attach them to workings.
* The alluvial layer is a bit dynamic based on the density of pits in any given area, I've tried to create shapes that convey information about where the good gravel was, sometimes that meant cutting out a couple of outlying dud prospecting pits. And I haven't worried a lot about tracing out underneath the town, not much point for the modern prospector! In some places, property owners have filled in all the alluvial pits so well that it's barely discernible in the data, but I've punched the layer through a few of these for continuity, doubt the laws of nature change too often.
* None of this is ground truthed beyond the memories in my head of being out there over the years, some of the surfaced areas I'm sure are difficult to interpret in the Lidar, and no doubt I've probably marked out a few gravel borrow pits and minor hard-rock stuff as surfacing too. And there's tons of just one-off scattered pits throughout the field that are pretty tough to give much importance to when you're trying to summarise the whole lot.
Basic workflow was:
Grabbing the DEM tiles of interest off https://elevation.fsdf.org.au/
Install QGIS and merge the DEM raster tiles into one file
Install the Relief Visualisation Toolbox plugin and run the Sky-view Factor visualisation on the DEM
Go to the display properties for the new layer and bump the gamma down to 0.1 for best viewing.
Compare and contrast to the 1956 geological map and the Doug Stone prospecting maps which didn't have the luxury of a perfect laser scan when they were made...
* The usual, these files don't imply prospecting access to the ground covered, please check if you're allowed to prospect in any given spot before you head out.
* Pretty much all the decent hard-rock mines (and anything that to my eye looked like a linear row of shafts or pits) are there, the line is named if known but the state of putting names to mines at Heathcote is a dog's breakfast at the moment by the looks. Both the department maps and Geovic are woeful. I'm interested in the history so I'll be looking to update the file with more names when I can attach them to workings.
* The alluvial layer is a bit dynamic based on the density of pits in any given area, I've tried to create shapes that convey information about where the good gravel was, sometimes that meant cutting out a couple of outlying dud prospecting pits. And I haven't worried a lot about tracing out underneath the town, not much point for the modern prospector! In some places, property owners have filled in all the alluvial pits so well that it's barely discernible in the data, but I've punched the layer through a few of these for continuity, doubt the laws of nature change too often.
* None of this is ground truthed beyond the memories in my head of being out there over the years, some of the surfaced areas I'm sure are difficult to interpret in the Lidar, and no doubt I've probably marked out a few gravel borrow pits and minor hard-rock stuff as surfacing too. And there's tons of just one-off scattered pits throughout the field that are pretty tough to give much importance to when you're trying to summarise the whole lot.
Basic workflow was:
Grabbing the DEM tiles of interest off https://elevation.fsdf.org.au/
Install QGIS and merge the DEM raster tiles into one file
Install the Relief Visualisation Toolbox plugin and run the Sky-view Factor visualisation on the DEM
Go to the display properties for the new layer and bump the gamma down to 0.1 for best viewing.
Compare and contrast to the 1956 geological map and the Doug Stone prospecting maps which didn't have the luxury of a perfect laser scan when they were made...
