I’m reading an article that the authors talk about extracting values of SOA (slope of aspect). I can’t find anything related to that on Google.
This article reference is : ZHOU, Yi et al. Automatic detection of lunar craters based on DEM data with the terrain analysis method. Planetary and Space Science, v. 160, p. 1-11, 2018.
When they relate to SOA in the text they say: “SOA represents the rate of change of the aspect in the horizontal direction and is generally obtained by extracting the slopes from the aspect matrices of the DEMs. Mathematically, SOA is a derivative function of the aspect; therefore, the maximum value of the SOA is located at the dividing line between the inside and outside crater walls (that is, at the crater rim position). Therefore, the experiment needs to extract only the largest SOA values to identify the crater's rim position.”
Can anyone help me understanding that?