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<p style="margin-bottom: 13.0px;"><span style="font-size: 11.0pt;"><span style="line-height: 115.0%;"><span style="font-family: Calibri , sans-serif;">Hi all,</span></span></span></p>
<p style="margin-bottom: 13.0px;"><span style="font-size: 11.0pt;"><span style="line-height: 115.0%;"><span style="font-family: Calibri , sans-serif;">I have the following task: </span></span></span></p>
<p style="margin-bottom: 13.0px;"><span style="font-size: 11.0pt;"><span style="line-height: 115.0%;"><span style="font-family: Calibri , sans-serif;">I need to create a map with contour lines showing the thickness of one geological layer/horizon (actually not the true thickness, but the vertical extent is required, so if you drill down at one point, what is the distance between the upper and lower edge of the horizon). </span></span></span></p>
<p style="margin-bottom: 13.0px;"><span style="font-size: 11.0pt;"><span style="line-height: 115.0%;"><span style="font-family: Calibri , sans-serif;">The only data I have are two line features (shape files) of isolines with elevation values (in m NHN) of each the upper edge and lower edge of the horizon. </span></span></span></p>
<p style="margin-bottom: 13.0px;"><span style="font-size: 11.0pt;"><span style="line-height: 115.0%;"><span style="font-family: Calibri , sans-serif;">My approach would be something like this, but I can’t figure out how exactly to do it:</span></span></span></p>
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<li><span style="font-size: 11.0pt;"><span style="line-height: 115.0%;"><span style="font-family: Calibri , sans-serif;">Create a raster from each line feature (did that, but only the lines are rastered, so would need a polygon to get a plane? How do that? How can I include the elevation values of the lines into the polygon?)</span></span></span></li>
<li><span style="font-size: 11.0pt;"><span style="line-height: 115.0%;"><span style="font-family: Calibri , sans-serif;">Interpolate the elevation values inbetween the isolines to receive a plane of elevation values (in my opinion would need a polygon to get a plane, but for interpolation input Points are needed? And which interpolation method? Also, some of the isolines are offset by faults, so need sharp edges in these areas, how to integrate that in the interpolation?)</span></span></span></li>
<li><span style="font-size: 11.0pt;"><span style="line-height: 115.0%;"><span style="font-family: Calibri , sans-serif;">Then calculate the vertical distance at each point in the area between the two planes to get the thickness (how, which tool does that?)</span></span></span></li>
<li><span style="font-size: 11.0pt;"><span style="line-height: 115.0%;"><span style="font-family: Calibri , sans-serif;">Create a raster showing the thickness throughout the area in colour range</span></span></span></li>
<li style="margin-bottom: 13.0px;"><span style="font-size: 11.0pt;"><span style="line-height: 115.0%;"><span style="font-family: Calibri , sans-serif;">Add contour lines showing the thickness of the horizon</span></span></span></li>
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<p style="margin-bottom: 13.0px;"><span style="font-size: 11.0pt;"><span style="line-height: 115.0%;"><span style="font-family: Calibri , sans-serif;">Maybe there is even a better and probably much simpler way to do this. However, I am only a beginner in QGIS, python and statistics. So any help and easy to understand tips will be very much appreciated. I am using QGIS 3.10.11 by the way.</span></span></span></p>
<p style="margin-bottom: 13.0px;"><span style="font-size: 11.0pt;"><span style="line-height: 115.0%;"><span style="font-family: Calibri , sans-serif;">Best regards,</span></span></span></p>
<p style="margin-bottom: 13.0px;"><span style="font-size: 11.0pt;"><span style="line-height: 115.0%;"><span style="font-family: Calibri , sans-serif;">Eva</span></span></span></p>
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