. Collected reprints / Atlantic Oceanographic and Meteorological Laboratories [and] Pacific Oceanographic Laboratories. Oceanography Distance Explosion'1 Water Detector Sediment. Rock Figure 17. The travel times of sound waves refracted through water, sediment and rock layers are plotted on a time-dis- tance graph. The sound velocities through the different materials are derived from the slopes of the corresponding segments of the time-distance curve and the thicknesses of the layers from their intercepts on the time axis (From Smith, 1968, fig. 2). it, and where the velocity con
. Collected reprints / Atlantic Oceanographic and Meteorological Laboratories [and] Pacific Oceanographic Laboratories. Oceanography Distance Explosion'1 Water Detector Sediment. Rock Figure 17. The travel times of sound waves refracted through water, sediment and rock layers are plotted on a time-dis- tance graph. The sound velocities through the different materials are derived from the slopes of the corresponding segments of the time-distance curve and the thicknesses of the layers from their intercepts on the time axis (From Smith, 1968, fig. 2). it, and where the velocity contrast between layers is sufficiently great to refract the energy. This means that the refraction method is blind to a lower velocity layer underlying higher velocity layers such as sedi- ments underlying rocks. Magnetic Method The magnetic method is used to delineate geological structures associated with petroleum, to measure thickness of sediment above mag- netic basement rocks, and to locate concentrations of magnetic (iron- bearing) minerals on or beneath the sea floor. The magnetic method depends on accurately measuring anomalies of the looal geomagnetic field produced by variations in the intensity of magnetization residing in magnetized sediments and rocks. The magnetization is due partly to induction in the earth's magnetic field and partly to permanent (rema- nent) magnetization. The induced intensity depends primarily upon the magnetic susceptibility of the materials and the present magnetizing field. The susceptibility is almost entirely controlled by the quantity. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Atlantic Oceanographic and Meteorological Laboratories; Pacific Oceanographic Laboratories; United States. Environmental Science Services Administration. Research Laboratories; Environm
Size: 1351px × 1850px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookcollectionamericana, booksponsorlyrasismemb
