Gully incision development on scoria cones: different behaviors in three volcanic fields reflect environmental conditions.

A consequence of alluvial processes acting on scoria cones is the development of a drainage network composed of radially distributed rills and gullies parallel to the volcanic edifice's downslope direction. This work focuses on the quantification of the degree of development of the drainage network by applying the Average Erosion Index method to scoria cones from the arid to semi-arid Lunar Crater volcanic field and comparing with previously obtained results from two tropical volcanic fields (Sierra Chichinautzin volcanic field and Paricutin-Tancitaro region, both in central Mexico). The results show that the method helps to determine geomorphic age relations when calibrated separately for each field. Furthermore, the differences in the resultant rates at which AEI varies as a function of time obtained for the three studied fields indicate that the method provides a tool to quantify the effects of different alluvial rates at volcanic fields across various environments.