Recent studies have shown that the presence of sand ripples on the seabed improves sonar detection of buried mines at sub-critical angles. Sidescan sonar data of ripples off on the west Florida shelf were collected as part of ONR's Ripples Departmental Research Initiative (DRI) September 26-29th and November 7-9th, 2004. Hurricane Ivan, the strongest storm of the 2004 hurricane season, passed over the experiment site a week before the first data collection. This study focuses on the ripples created by Ivan. Average relict ripple wavelengths left after the storm were found to increase with water depth (50 cm, 62 cm, and 83 cm in 20, 30, and 50 meter water depths) despite the fact that orbital diameter decreases with water depth. Ripple prediction requires information about surface gravity waves and sediment grain size. The most reliable offshore wave field available was created with Wavewatch III by Naval Postgraduate School scientists. These waves were inputted into Delft3D WAVE, incorporating the nearshore wave model SWAN to predict waves at the locations where ripples were measured. Orbital motions at the seabed and grain size were inputted into a time-dependent ripple model with varying dissipation parameters to estimate sand ripples created by Hurricane Ivan. Ripple wavelength was found to be more strongly dependent on grain size than wave dissipation. / Contract number: N62271-97-G-0026. / US Navy (USN) author.

Reissued 30 May 2017 with Second Reader’s non-NPS affiliation added to title page. / Approved for public release; distribution is unlimited / The purpose of this thesis is to characterize typical levels of vibrational noise on the ocean floor to ascertain the vibration's effect on possible future bottom mounted sensors. The data used for this thesis was obtained from publicly available recorded information from four ocean bottom seismometers (OBS). The OBSs were located in two geographical choke points: the Luzon Strait and west of the Strait of Juan de Fuca. These highly trafficked choke points were considered to be a good representation of where these experimental bottom mounted sensors might be located should they be built. Unix-based seismic processing software available from the Incorporated Research Institutions for Seismology (IRIS) proved essential to obtaining calibrated data, and the methodology used to get the calibrated data is discussed in detail. The results showed that one OBS out of the four was highly variable, with decibel levels varying widely from day to day. The other OBSs remained fairly consistent. In addition, there were no common discrete frequencies between sensors that were in the same geographic area. Recommended future research involves the study of environmental effects on the OBSs, additional research to correlate the results observed in the Luzon Strait, and a look into the electronic noise floors of the OBSs used. / Lieutenant Commander, United States Navy

Thesis (Ph. D.) University of Southern California, 1969.

Thesis (M.S.)--Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1979. / Contract no.: N00014-77-C-096; NR 083-004. Includes bibliographical references (p. 132-133).

Thesis (Ph.D.) - University of St Andrews, January 2009.

Thesis (M.S.)--Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1979. / Contract no.: N00014-77-C-096; NR 083-004. Includes bibliographical references (p. 132-133).

Thesis (Ph. D.)--Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1981. / Ch. 2 written by John Crowe, Richard P. Von Herzen and Kenneth E. Green; ch. 3 written by John Crowe and Armand J. Silva; ch. 4 written by John Crowe and Russell E. McDuff. Vita. Grant no.: OCE 79-02792. Includes bibliographical references.

Thesis (M. S.)--Earth and Atmospheric Sciences, Georgia Institute of Technology, 2007. / Lowell, Robert, Committee Chair ; Long, Tim, Committee Member ; Newman, Andrew, Committee Member.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Science, 1982. / Supervised by Sean C. Solomon. Vita. Includes bibliographical references (leaves 312-321).

Thesis (Ph. D.)--Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1982. / Includes bibliographical references.