Tuning the CARIS implementation of CUBE for Patagonian Waters.pdf

3. ENVIRONMENT OF THE PATAGONIAN FJORDS AND
CHANNELS.
This chapter explains the variability in the seafloor geomorphology in the
Patagonian region. As was explained previously, the seafloor geomorphology has a direct
influence in the bathymetric data collected. Possible issues such as strong backscatter
variability between different sediment types and extreme morphology are common in the
Patagonian water. Consequently, the bathymetric data collected will be strongly affected
by noise-data associated with sidelobe interference causing sea-bottom mistracking. Then
CUBE, in some cases, will attempt to estimate the most likely depth from cluster outlier
points that do not satisfy the normal properties of outliers [Calder and Smith, 2004].
3.1 Geomorphology of the Patagonian Channels and fjords.
Throughout history a series of glaciations have affected the earth (the last
glaciations occurred approximately 12,000 years ago). During these periods, glaciers and
sea level have changed the morphology of sea bottom on the continental shelf. Thus, the
crust has been deformed by erosion plus deposition actions. Basins kilometres in length
are generated by the action of glaciers (i.e., ice withdrawal) and filled up by the ocean
when sea level arises.
The region between Puerto Montt and Cabo de Hornos (Figure 3.1) is subject to
tectonic subduction and glacial sedimentation. The ocean has penetrated into the
intermediate depression, showing a variable morphology of gulfs, channels, estuaries and
fjords.
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