2012


Angel Torrens-Bonano

Angel Torrens-Bonano


Years participated in RESESS:
2011
2012


An Overview

Major: Geology
Academic Affiliation: University of Puerto Rico at Mayaguez
Research Mentor: Anne Sheehan, CU
Computer Mentor: Kyle Bohnenstiehl, UNAVCO
Writing Mentors: Lon Abbott, CU and Val Sloan, UNAVCO
Peer Mentor: Kara Epple


Biography

Angel grew up in Luquillo, a beach town on the eastern side of Puerto Rico. He is currently studying geology at University of Puerto Rico Mayaguez Campus on the west coast. He has always been intrigued by events such as hurricanes, thunderstorms, earthquakes, and tsunamis. When exploring the course selections at UPR-Mayaguez, he discovered the opportunity to major in geology. He says that taking the first introductory geology class changed his world. When Angel is not at school with friends, he spends a lot of time with his family.


Abstract

Shallow subsurface conductivity survey of Betasso Watershed, Colorado

Surveys of the shallow subsurface in Betasso Watershed, CO, were conducted using an EM-31 conductivity meter that has high horizontal resolution (~3.5m), and vertical resolution of ~6 m. In this study, we examine whether subsurface conductivity is higher in areas of steeper slopes or varies with slope aspect. Conductivity in subsurface sediments could be expected to be greater in gently sloping areas versus steeply sloping areas because water and clay sediments tend to accumulate in topographic lows and to be washed away from steeper slopes. We might also expect conductivity to be greater on north-facing slopes, where vegetation tends to be more abundant. We created a map of the electrical conductivity of part of Betasso watershed by contouring ~2,900 EM-31 data points. We created slope steepness and aspect maps using a 1m resolution DEM obtained from LiDAR that was collected as a part of the Boulder Critical Zone Observatory project, using GIS. We correlated the conductivity map with the slope and aspect using data from areas where both types of data were available. Results shows that subsurface conductivity values were not correlated with slope or aspect. It may be that the EM-31 measurements average conductivity at a depth that is much greater than the depth to which clays and water accumulate in the soil, and that only conductivity values closer to the surface actually vary with slope or aspect. Variations in the EM-31 data may therefore be more strongly controlled by depth to bedrock. Combining the EM-31 data with DC resistivity measurements shows promise for creating a map of depth to bedrock, which will have significance for geomorphic studies on bedrock weathering and for environmental hydrogeology studies.