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You could drape your geological polygons on the elevation surface you created to make them 3D. Two ways in 3D Analyst are Interpolate Shape and Add Surface Information. For an explanation of both see: http://resources.arcgis.com/en/help/main/10.1/index.html#//00q80000005m000000


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Usually terrain models derived from remote sensors will have their initial accuracy evaluated using blind control methods. For example with LIDAR, the remotely sensed measurements are often compared to survey-grade control points (the blind control) taken on the ground in various land covers (woods, open areas, etc) to assess the penetration and accuracy of ...


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I would use this approach: Add flood deep to DTM to create a new surface raster (use Plus (3D Analyst) tool). Drape the flood raster to the new surface.


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You need to use the DTM as the base height for your flood depth raster and calculate a new height by adding the flood depths raster value to the dtm base height as a vertical offset. bearing in mind that water is flat (waves aside), you could also use a flat plane and calculate the flood limits as a height above sea level and set the height of the plane ...


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Some literature on this topic: COLOSIMO, G., CRESPI, M., DE VENDICTIS, L., JACOBSEN, K. (2009). Accuracy evaluation of SRTM and ASTER DSMs. In Proceedings of the 29th EARSeL Symposium, Chania, Greece. GOROKHOVICH, Y., & VOUSTIANIOUK, A. (2006). Accuracy assessment of the processed SRTM-based elevation data by CGIAR using field data ...


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Here is a good one (one of the authors is a regular user on GIS SE). Evans, Jeffrey S.; Hudak, Andrew T. 2007. A multiscale curvature algorithm for classifying discrete return LiDAR in forested environments. IEEE Transactions on Geoscience and Remote Sensing. 45(4): 1029-1038. Look on Table II (page 1034). The authors used lidar ground returns ...


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In ArcGIS you can use the Viewshed tool (Spatial Analyst Tools > Surface). The Viewshed lets you calculate the surface locations visible to a set of points or lines (see the documentation).


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This looks like a valid workflow for this task. However, depending on the level of accuracy that you work with, you will miss out on things like pipes under roads allowing for ditches and small creeks to flow past the road. These would probably require some field work to identify though. You don't mention which software you use, but for ArcMap point (6) ...


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This is how I would do it: Convert your line to a raster (Polyline to Raster) Convert the raster to points (Raster to Point) Add Z value from the raster to the points (Extract Values to Points). A new field named RASTERVALU with the raster Z value is added. Turn the points into a feature layer and select the point with the minimum Z field value using for ...


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Be wary of stating, out the gate, that something is producing "wrong" results. The phenomena of slope percent approaching infinity as slope degrees approach 90 is well known. You could just truncate slopes > 100 == 100. ESRI actually provides a very nice description on how slope is calculated. You could try the calculation in degrees to make sure that ...


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This is a very common error when using ArcHydro, although the exact text and in which function it appears might differ slightly. You should check out the answer and comments in this question. But in short, what is most likely to solve your problem is to store all data and your project on C:/ instead of a network drive.


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I had to do something rather like this for my masters thesis, but with much fewer observer and target points. I'm not aware of a reasonable way to create a complete raster of "visible area," at least not one that wouldn't take a long time. Repeatedly running Viewshed, once for each centroid of the raster's cells, would certainly work... but as you've, ...



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