| dc.description.abstract | Traditionally, seabed layers were
determined by using conventional mechanical
methods like boreholing, which retrieved the
strata at a single point at one time. Later it was
developed to various acoustic remote sensing
techniques which can determine layers
robustly, with less cost. Sub Bottom Profiler
(SBP) is an effective method used to identify
and describe the layers of sediments under the
seabottom. SBP is almost similar to an echo
sounder, but portion of the sound pulse is
penetrating beneath the seafloor and reflected
off of the strata layers. These refracted
acoustic signals will show any sort of density
disturbance. Sub bottom systems have been
used to detect and measure the thickness of
sediment deposits, identify buried objects, and
define the bedrock layer of a basin.
Transducer frequency and pulse length are the
key aspects on the SBP system performance.
Absorption losses are proportional to the
transmitting frequency. Long sound pulse
lengths required more energy and resulting
deeper penetration but decreasing the system
resolution. The Stratabox HD is a pinger type
SBP having the capability of detecting the soft
sediment layers in high resolution. The
objective of this study was to carry out a geophysical investigation of the Colombo Port
using the SBP. Data was collected at the Jaya
Container Terminal (JCT) basin. Sub-bottom
fence diagrams were generated with Hypack
software and results were validated using the
existing borehole samples. The initial sub
bottom soft layers were closely matched with
the borehole sample data. | en_US |
