Graduate student’s investigating Arizona’s earth fissures
Research into the origin and impact of earth fissures in Arizona is not solely the province of the Arizona Geological Survey. Graduate student researchers at the University of Arizona and Arizona State University are investigating strategies for mapping fissures and for communicating related hazards for informing the public.
Below are abridged summaries of two studies: Emily Zawacki’s informative science communication video, and from Bellavance and others exploration of fissure geometries.
“Earth fissures are long, narrow cracks in the ground that form where the ground is sinking. They can erode very quickly, posing a hazard to nearby infrastructure. In Arizona, land subsidence--the sinking of the earth--is caused by groundwater withdrawal, meaning that earth fissures are a man-made--or anthropogenic--hazard.
Joe Cook, the Earth Fissure Project Manager at the Arizona Geological Survey (AZGS), monitors new and existing earth fissures. You can view a map of earth fissures in Arizona on the AZGS's Natural Hazards in Arizona Viewer (https://uagis.maps.arcgis.com/apps/we...). Additional information can be found at the AZGS Earth Fissure website."
Video by Emily Zawacki, GSA Science Communication Intern, Ph.D. Candidate Arizona State University. Citation: Zawacki, E., 2019, Understanding Earth Fissures: A Man-Made Geohazard.
“As part of a Master's project, ARSC (Arizona Remote Sensing Center) has been working on a project using remotely sensed data to measure and map Earth Fissures near Casa Grande, Arizona.”
“Remote sensing allows for alternative methods for measuring Earth fissures, oftentimes with less work in the field. For this project, ARSC used an unmanned aerial vehicle (UAV) to capture hundreds of high resolution images of a single fissure to create a 3-D model using a technique called Structure-from-Motion (SfM).”
"This technique estimates the three dimensional structure of an object using only two dimensional images, like those taken from a UAV."
Bellavance, B., Leeuwen, W.v. and Conley. C., 2019, Earth Fissure Mapping: A StoryMap.