Creating bathymetry maps using sonar data in SAGA

Question

I am a geologist, however somewhat of a newbie to GIS.
As a personal project, I am looking to create some bathymetric maps of some local fishing lakes.
I am looking to do this using free open source programs at zero cost, and have initially downloaded SAGA. I am aware that QGIS may be an alternative if that's better suited.
I have plenty of raw sonar data in lat/long/depth format which effectively gives me xyz.
What I would like to know is a can anyone provide me with a basic outline of how to import and transform this data into a 3d bathymetric map to show a contoured / shaded lake bed surface?

Luis Perez · Answer

SAGA is a good choice, to start with.
To generate a surface (a digital model of your data) you must interpolate
Procedure at SAGA:

Save your data x,y,z in a data table, csv, txt, xlsx.

Activate SAGA, in Open locate and load the file

Then on menu Geoprocessing > Shapes > Construction >Generate shapes.
In the dialog box shown, configure the input fields (x,y,z) and as output create, shape type point

You can visualize your points by selecting them, right click add to map

INTERPOLATION: You have many options, go to Geoprocessing > Grid > Gridding > interpolation or Spline interpolation

Each method has its own configuration options. In addition, you can configure the evaluation of error metrics to assess the performance of the method.

Click on Ok, the surface is generated, visualize it with add to map

Isolines, contoured
Geoprocessing > Shapes-Grids Tools> Vectorization > Contour lines for Grid

Shaded

RogueWave · Answer

I am working on the same problem. XYZ data to a mesh....don't think ppl understand a mesh
my navigation software on my boat exports in XYZ lat/long/depth import into GIS does not work....Enclosed photo is Bathymetric mesh in nav software...nice mesh
Python has XYZ import features????

Creating bathymetry maps using sonar data in SAGA

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