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Accession Number ADA571996
Title Analysis of Deep Seafloor Arrivals Observed on NPAL04.
Publication Date Dec 2012
Media Count 94p
Personal Author I. A. Udovydchenkov M. A. Dzieciuch P. F. Worcester R. A. Stephen S. T. Bolmer
Abstract This report gives an overview of the analysis that was done on Deep Seafloor Arrivals since they were initially presented in Stephen et al (2009). All of the NPAL04/LOAPEX (North Pacific Acoustic Laboratory, 2004/Long Range Ocean Acoustic Propagation Experiment) data on three ocean bottom seismometers (OBSs) at approximately 5,000m depth and the deepest element of the deep vertical line array (DVLA) at 4250m depth has been analyzed. A distinctive pattern of late arrivals was observed on the three OBSs for transmissions from T500 to T2300. The delays of these arrivals with respect to the parabolic equation predicted (PEP) path were the same for all ranges from 500 to 2300km, indicating that the delay was introduced near the receivers. At 500km range the same arrival was observed throughout the water column on the DVLA. We show that arrivals in this pattern converted from a PEP path to a bottom-diffracted surface reflected (BDSR) path at an off-geodesic seamount.
Keywords Acoustic arrays
Bdsr(Bottom-diffracted surface reflected)
Brsr(Bottom-reflected surface-reflected)
Deep oceans
Deep seafloor arrivals
Depth
Diffraction
Dsza(Deep shadow zone arrivals)
Dvla(Deep vertical line array)
Obs(Ocean bottom seismometers)
Ocean bottom
Pep(Parabolic equation predicted)
Range(Distance)
Reflection
Seismometers
Time
Triangulation

 
Source Agency Non Paid ADAS
NTIS Subject Category 47C - Physical & Chemical Oceanography
48F - Geology & Geophysics
Corporate Author Woods Hole Oceanographic Institution, MA. Dept. of Geology and Geophysics.
Document Type Technical report
Title Note Technical rept.
NTIS Issue Number 1316
Contract Number N00014-10-1-0510

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