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Entering survey plot lines in Google Earth

PostPosted: Jul 12, 2020 7:10 pm
by Leitmotiv
Is there a method to entering survey data in Google Earth tied to a known cave entrance location?

Re: Entering survey plot lines in Google Earth

PostPosted: Jul 13, 2020 2:48 pm
by chac
Hi Matt,

Most modern cave survey programs will export both GIS shapefiles and KML or KMZ plots from survey data they have processed. Have a look at the GE help files just to check what GIS shapefiles are needed. Both Walls and Compass export both files. Just make sure you are georeferencing the cave before processing in the cave survey program.

The most expedient way is to export a KML file. If you have GE installed in your computer just double-click the exported KML file you exported and this will open GE.

Jim

Re: Entering survey plot lines in Google Earth

PostPosted: Jul 14, 2020 5:13 pm
by Leitmotiv
How would you determine the Vertical coordinate in Compass from a UTM coordinate that only shows the Easting and Northing?

Re: Entering survey plot lines in Google Earth

PostPosted: Jul 15, 2020 3:43 pm
by chac
Your survey data starts at a singular Zero Datum (ZD) survey station. The depth of the cave is determined from/relative to this unique station. There may be alternative cave entrances below ZD ("deeper"), and some above ZD ("higher"). Cave depth is measured from the highest to lowest survey stations.

All your survey data is entered in a cave surveying program (not in GE), then converted by that software for use in the GE program. The UTM Easting and Northing are the X and Y graph coordinates to locate the point on a suitable plan map, like a topo map. The Z coordinate (relative depth of each survey station) is calculated from the depth assigned to ZD in the cave survey program. Most survey programs have a dedicated file where you store the coordinates (X,Y) and altitude (Z) of the ZD survey station. In Compass this is called a Project or .MAK file.

PM me if this is not clear. :waving:

Jim