Related Experiment Video
Updated: Jun 19, 2026

Kinematic History of a Salient-recess Junction Explored through a Combined Approach of Field Data and Analog Sandbox Modeling
Published on: August 5, 2016
Some Seismic Profiles near the Western End of the Puerto Rico Trench
1The Hudson Laboratories, Columbia University, Dobbs Ferry, New York.
Abstract:
A cooperative program of seismic refraction profiling was completed in the vicinity of the Puerto Rico Trench by Hudson Laboratories, Woods Hole, Lamont, and Texas A. & M. Profiles completed near the western end of the Trench were analyzed at Hudson Laboratories. Five seismic layers are indicated below the water layer. The thickness/velocity relationships are as follows: 5.1 km of 1.5 km/sec. (water); 1 km of 1.7 km/sec. (sediment); 1.5 km of 3 km/sec. (metamorphics?); 2 km of 5.5 km/sec. (basement); and 2 km of 7.1 km/sec. (high speed basement). Below these, typical Moho velocities of 8.1 km/sec. were measured. Total depth to Moho ranges from 9 to 12 km below sea level, the greatest variation occurring in the basement layers. The least depth was measured 65 miles north of the Puerto Rico Trench.
More Related Videos
Related Concept Videos
Resistivity
Profile Leveling and Cross Sections
Taping Over Different Ground Profiles
Topographic Surveying and Contours
Precipitation Gravimetry
In determining nickel by gravimetric analysis, a precipitant of ethanolic dimethylglyoxime is added to a hot nickel salt solution. This is quickly followed by the dropwise addition of dilute ammonia solution until precipitation occurs. A...
Gravimetry: Overview
In precipitation gravimetry, the analyte is converted into a precipitate and weighed. For example, the silver content in a sample can be estimated by precipitating and...

