Perry Byerly

Subcontinental Structure in the Light of Seismological Evidence

Publisher Summary This chapter discusses the subcontinental structure using seismological evidence. Several methods employed to investigate the subcontinental structure are refraction method, the reflection method, methods of computation, and dispersion of surface waves. The chapter also discusses the concepts of earthquakes, its reflection, and dispersions from the perspective of different geologists. The study of waves recorded on seismographs from explosions has the advantage over earthquake studies in that the position of the source is known. Frequently, when the explosion is not accidental, arrangements have been made to record the exact time of the explosion. It was realized earlier that such observations would lead to a final and exact interpretation of Earth structure. However, it has only led to the conclusion that the Earth is quite varied in its constitution. The chapter also presents several earthquake explosions such as Oppau explosion, quarry blasts in Germany, and La Courtine in France.

Report of special committee on cooperation with International Commission for the Study of Tidal Waves

The American Committee has representatives from the weather Bureau, the Hydrographic Office of the Navy Department, the Coast and Geodetic Survey, the University of California, and Johns Hopkins University. It has a permanent function to collect all available information regarding unusual invasions of the shore by the sea. During the year a report was made to the International Commission regarding waves in southern California and also regarding sea-movements accompanying the Panama earthquake of June 1934. At the initiative of the Navy Department, which required better understanding of the possibility of seismic sea-waves accompanying an earthquake like that of Long Beach in 1933, the Chairman compiled a list of known tidal waves of history and it was published in the Bulletin of the International Commission as a contribution of the Committee.