An Overview
Major: Geology
Academic Affiliation: niversity of Puerto Rico at Mayagüez
Abstracts
2007- Historical seismicity of the northeastern region of Russia: A perspective on the M7.6 earthquake at Koryakia, Russia
A major earthquake which occurred near Koryakia, Russia during April 20, 2006 is analyzed and given perspective in contrast with the historical seismicity, plate tectonics and the local geology of the area. The relevance of this earthquake is that it occurred in a complex geological area, where the locations of the plate boundaries are not well known and no major earthquakes were recorded since 1900. This event is evaluated through a comparison with past events and plate tectonic models. Our approach to analyzing the tectonic regime of the Koryakia region included, conducting a survey of published articles on the geology of the area, mapping of the regional seismicity in ArcGIS and creating models of 3D visualization of the region using 3D Seismicity Viewer. An analysis of the resulting maps and models gives us a new perspective of what mechanisms triggered this major M7.6 earthquake that was the cause of leaving 40 people injured and some buildings and water supply systems badly damaged. The earthquake caused an estimated 55 million U.S. dollars worth of damage. The goal of this research has been to make a well structured tectonic summary, which can be used as a reference by the USGS and the scientific community for future events that may occur in or near the Koryakia region. Our research indicates that the possible cause of the event is a release in stress due to the compression near a proposed boundary between the Bering microplate and the North American plate.
2008- Terrestrial laser scanning study of gully erosion at West Bijou Creek, Arapahoe County, Colorado: An investigation on field acquisition and data processing
Terrestrial laser scanning (TLS) or ground-based LiDAR (light detection and ranging) is a relatively new technology that digitally maps geological outcrops at centimeter-to-millimeter resolutions. This paper reports the results of a trial TLS project that has two main aims: collecting scans for monitoring gully erosion, and conducting a survey to connect field methods of TLS with geomorphology. The site of this TLS survey was located in Arapahoe County, Colorado, and data collection consisted of a three-day campaign. This project focused on a new approach to analyzing and measuring deformation and erosion in gully-dominated landscapes. Our approach to the survey consisted of going to the field with an Optech scanner to acquire the data, searching for different field acquisition strategies, practicing with data processing, and making a web page of the project for the scientific community. A preliminary terrain model was made in Polyworks software using only 20 percent of the scans; this provided insight into how the landscape model can look in the future. The long-term goal of this research is to keep track of the changes in the morphology of the gullies located at West Bijou Creek in Colorado using Real Time Kinematic GPS (RTK-GPS) and Terrestrial Laser Scanning (TLS). Because applications of TLS in geology and geophysics are evolving rapidly, in this project a web page including a forum is provided to the scientific community with a summary of current field acquisition practices for sharing ideas and discoveries.