COOPERATION IN SEISMIC MEASUREMENTS OF CRUSTAL STRUCTURE IN MINNESOTA.
Abstract
Eighty-two one-ton charges of dynamite were detonated under controlled conditions at pre-selected points in Lake Superior. A network of seismic crews recorded the vibrations produced by these explosions. The frequency spectra are in many ways similar to those found for the Gulf of Maine by Nakamura and Howell (BULL. SEIS. SOC. AM. 54:9-18, 1964). There are frequent minima in the spectrum presumably due to interference (Nakamura, BULL. SEIS SOC. AM 54:1-8, 1964). These holes display no so-far-identified pattern. Unlike the Maine records, the Minnesota records do not show a strong difference in the spectrum between the direct and critically refracted pulse. This could mean that the Mohorovicic discontinuity in Minnesota is sharper than in Maine.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 15, 1964
- Accession Number
- AD0610944
Entities
People
- B. F. Howell Jr.
Organizations
- Pennsylvania State University