Morphometry of volcanic features associated with Los Coconucos Volcanic Chain (CVLC), Colombia

Abstract

The Coconucos Volcanic Chain (CVLC-from its acronym in Spanish) is made up by 14 volcanic centers (nine composite volcanoes and five monogenetic volcanoes) oriented along the Coconucos Lineament. Two more centers, maar-type volcanoes, are also located to the SW, in the vicinity of the CVLC. To study the development of these volcanic centers, the ellipticity (e_i ) and irregularity (i_i) morphometric parameters as well as the base-toheight H/W_B for composite volcanoes and the height-of-cone to width-of-cone Hco/Wco ratios for monogenetic centers, were evaluated. The values for morphometric parameters and dimensional ratios vary as follows:1.27<e_i <3.24; 1.12<i_i <1.53; 0.04<H/W_B<0.24 and 0.02<H_co/W_co<0.34. Graphs of morphometric parameters ordered according to the spatial position of the volcanic centers allowed identification of partial tendencies in the evolution of composite volcanoes and patterns in the state of preservation for monogenetic centers: ei increases to the SE; i_i decreases to the SE; H/WB increases to the SE and Hco/Wco increases to the NE. Together, these values and patterns suggest not only variability of endogenous and exogenous processes that affect the shapes of volcanoes, but also possible cycles of constructive activity and affectation of morphology and morphometry of the volcanic structures.