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Seismology on Mars
A three-axis short-period seismometer has been operating on the surface of Mars in the Utopia Planitia region since September 4, 1976. During the first 5 months of operation, approximately 640 hoursExpand
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An experimental study of thermally induced microfracturing and its relation to volcanic seismicity
In this study, unconfined samples of basalt, sintered and bonded perlite, insulating firebricks, and paraffin were subjected to thermal gradients ranging from 15°C/cm to 100°C/cm. MicroshocksExpand
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Apollo Lunar Seismic Experiment - Final Summary
Processing and initial analysis of the entire set of Apollo lunar seismic data collected continuously from 1969 through 1977 have now been completed. Recent results include: 1) better defined deepExpand
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Lunar Seismicity, Structure, and Tectonics
Natural seismic events have been detected by the long-period seismometers at Apollo stations 16, 14, 15, and 12 at annual rates of 3300, 1700, 800, and 700, respectively, with peak activity at 13- toExpand
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Crustal structure in Southern Central America
Seismic data from explosions and local earthquakes are used to determine shallow crustal structure near Managua, Nicaragua, and to derive a complete crustal model for northern Costa Rica. A newExpand
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Meteoroid impacts as sources of seismicity on the moon
In conjunction with the Apollo lunar passive seismic experiment, a study was undertaken to determine the efficiency of meteoroid impacts on the lunar surface as potential sources of seismic energy.Expand
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Unusual animal behavior before earthquakes: A review of possible sensory mechanisms
To determine whether reports of unusual animal behavior before earthquakes are plausible, we have compared these reports with recent laboratory studies of animal sensory thresholds. Our majorExpand
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Evidence that biological activity affects Ocean Bottom Seismograph recordings
Brief and impulsive signals of uncertain origin appear regularly on records from Ocean Bottom Seismographs (OBS) of several institutions. These signals have been recorded on nearly all deployments ofExpand
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Lunar structure and dynamics - results from the apollo passive seismic experiment
Analysis of seismic signals from man-made impacts, moonquakes, and meteoroid impacts has established the presence of a lunar crust, approximately 60 km thick in the region of the Apollo seismicExpand
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Lunar near‐surface shear wave velocities at the Apollo Landing Sites as inferred from spectral amplitude ratios
The horizontal-to-vertical amplitude ratios of the long-period seismograms are reexamined to determine the shear wave velocity distributions at the Apollo 12, 14, 15, and 16 lunar landing sites.Expand
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