Is it possible to define a horizontal constraints so that more weight is given on the interpolation of the property horizontally rather than vertically. Similarly in kriging we can define a semi variogram with an orientation in 2d, and i would like to know if it can be done in 3d. Also what about the question regarding the elevations between the top and bottom of the soil formation. Is there a possibilty for v vol rst to consider data points in between top and bottom.
On Jun 28, 2018 03:40, "Moritz Lennert" <[email protected]> wrote: On 27/06/18 16:32, Francois Chartier wrote: > So therefore, my approach of generating a soil property at each > elevation and interpolating is a correct approach. > Is there a way that i can constrain the interpolation horizontally. Not sure what you mean by constraining the interpolation horizontally. You can create a 2D elevation map by interpolating all your height information of layer 1 (for example using v.surf.rst). Then you create a second elevation map interpolating the layer 2 height information, etc. Moritz > I. > Cant remember the module name i am using but i am generating the 3d > raster from the 3d data points directly. > > > On Tue, Jun 26, 2018, 23:38 Moritz Lennert, > <[email protected] <mailto:[email protected]>> wrote: > > On 27/06/18 03:59, Francois Chartier wrote: > > Hi, > > > > I am working with a data set that consists of borehole logs with > a Top > > of a layer (layer 1) and the top of the underlying layer (layer 2) > > (which is also the bottom of the overlying layer 1). Everything in > > between the elevation of top of layer 1 and top of layer 2 > correspond to > > a Layer 1 property. > > > > The thickness of Layer 1 varies and this layer may not exist > everywhere > > (pinches out). Above the Layer the property is different; in other > > words the property only starts below the Top of layer 1 until the > > underlying Top of the next layer. > > Not sure of the capabilities of the interpolation in Grass and > working > > with a very large data set (i cannot link every top of layers > together), > > my first approach was to create a each Layer property for every > > elevation slice along each Borehole axis, interpolating soil > properties > > at every elevation between Boreholes. > > > > I read on another forum that r3.in.xyz <http://r3.in.xyz> > <http://r3.in.xyz> can > > interpolate in 3D without a Property at every elevation slice, > > > > * while respecting the condition that above the Top of the layer 2, > > the property corresponds to the Overlying top layer 1, and > > * that the property is continuous until the next underlying > layer 3 - > > can someone confirm this? > > > > To provide a bit of background, borehole data bases, identify the > top of > > layer as encountered when drilling downwards, and provide the > elevation > > of the next layer (pick); in between the soil property is the same, > > however there is no data points. When interpolating, while there > is no > > data point in between the two geological picks, the property should > > still have weight in the interpolation process. > > > > I don't think r3.in.xyz <http://r3.in.xyz> is what you need. This > module aggregates 3D > point data into voxels. > > You probably want to use something like r.to.rast3. This would mean > interpolating each layer separately into 2D elevation maps and then > assemble them into 3D using r.to.rast3. > > Moritz >
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