Infrasound signals from earthquakes and other sources and upper crustal and source constraints from seismic observations of single-fired explosions in SE Arizona.

摘要

Elastic energy transfer from one material to another is a commonly observed phenomenon in nature. This dissertation describes, analyzes, and utilizes some of this energy transfer phenomenon for waves in the atmosphere and the solid earth. The dissertation is composed of two parts. The first part is comprised of three papers on the infrasound signals from earthquakes and impulsive sources and involves energy transfer from the solid earth to the atmosphere. The second part uses a well-documented contained explosive source for constraining the shallow velocity structure or layering in the solid earth and interpreting the coupling of the explosive source.; Paper one described the low frequency sound, infrasound (0.02--1.0 Hz), which was generated by an earthquake through the coupling from the solid earth to the atmosphere and recorded by two seismo-acoustic arrays in the Republic of Korea. The infrasound from the earthquake is classified into three types: local infrasound generated at the receiver, epicentral infrasound generated in and around the earthquake epicenter, and diffracted infrasound generated by focusing of seismic waves by the topography between the source and receiver.; Paper two is an extension of the utilization of local infrasound signals for acoustic gauge calibration to the high frequency (1--4 Hz) using a regional earthquake occurred in the East Sea, the Republic of Korea (MW = 5.1). The methodology was performed in the time domain while that in the paper one was done in the frequency domain.; Paper three documents for the first time a temporary but very efficient waveguide that can form at the thermal boundary between the atmosphere and the ocean. A series of dispersed infrasound signals were observed within eleven minutes at one seismo-acoustic array in the Republic of Korea.; Paper four focuses on seismic waves. It is motivated by the long-standing lack of physical understanding on S-wave generation from explosions. Solution of this problem is separation of both propagation path and source effects from the explosion detonated in a copper mine in southeastern Arizona. The two-dimensional propagation path effects is constrained by a densely sampled set of seismometers and the seismic source was constrained with the near-source seismic recordings in the copper mine. (Abstract shortened by UMI.)