 Hello, in this video we're going to calculate the depth of wells using map algebra. For this purpose we have a raster layer with the ground water levels in the wells. We also have a raster layer with the DTM, the digital terrain model. We can use the raster calculator to then calculate the depth of the wells, which is the level of the surface from the DTM, so we double click on DTM, we click on minus to subtract the height of the ground water from the ground water level raster, and we save the result as well-debt.tiff. And I click OK, I get this result which is a continuous raster with for the well pixels the depth of the well. We can style continuous rasters with single-band pseudo-color, and in this case we can use a color ramp. Let's use blues, the darker the blue, the deeper the well. We can also use map algebra with the raster calculator if we're interested in which wells we consider as not deep and deep. So let's use a value of 40, so all the wells that are less than 40 meters deep will get Boolean true and all the others will get Boolean false. And I call the output not deep.tiff, click OK, I can paste a Boolean style that I had in memory here and I can edit the labels too deep for the false pixels and not deep for the true pixels. So in this video you've learned how to calculate the depth of wells using map algebra with the raster calculator. You've also identified the deep and not deep wells using map algebra.