Abstract
Late Cenozoic cooling is thought to be the main driver of erosion globally. Glacial/interglacial cycles modify river hydrology and therefore the balance between erosion, transport, and deposition of sediments in active orogens. My research aims to understand the impact glacial/interglacial cycles had on erosion/sedimentation rates in low latitude tropical mountains, like the Northern Andes. The research question addressed is: What is the primary process responsible for the deposition of thick (up to 300m) fill terraces in steep mountain catchments? I hypothesize that (1) these terraces were formed in periods of low river discharge (interglacial) when bedload transport capacity was reduced. An alternative scenario is (2) that sediment production was enhanced by high rock uplift rates via earthquakes. If the climate trigger is feasible, this implies that low-latitude tropical mountain ranges are sensitive to rainfall fluctuations through increase/decrease in sediment production and that climate change may have a greater impact on the future of tropical rivers. Otherwise, erosion rates in low-latitude mountains are regulated by coseismic deformation that overprints climate activity, even over short-time scales.
Bio
Helbert Garcia-Delgado is a geologist pursuing a Ph.D. in Earth Sciences at Syracuse University. He holds a B.S. in Geology from the Industrial University of Santander, in his native Colombia. Since graduating in 2015, Helbert has been engaged in landscape evolution and natural hazards studies in the mountainous regions of the Colombian Andes where he has cultivated many skills in geological mapping, data acquisition, and field sampling for geochronology lab tests. Besides Helbert’s abilities in carrying out fieldwork, he has been continually improving laboratory and computational skills during his studies at the Department of Earth and Environmental Sciences at Syracuse University. At this point of his young career, Helbert has been productive in scientific communication, publishing 13 first-authored scientific articles over the past 5 years; some of them in top-ranked journals such as Geomorphology and Global and Planetary Change. During his job as Junior Geologist for the Colombian Geological Survey, Helbert was committed to outreach activities with rural communities, learning how to effectively synthesize and communicate geologic research to a non-academic audience.