High resolution geophysical surveys and sediment sampling were undertaken along Vitória Bay in order to acoustically map the seabed. Integrated analysis of sidescan sonar and seismic records allowed the recognition of 4 distinct echo facies. Echo facies Type 1 is associated with no penetration of the acoustic signal and high backscatter sonograms with bedforms. This echo facies is related to sandy beds. Echo facies Type 2 is mainly associated with sandy mud bottoms, showing a high penetration of the acoustic signal and low backscatter sonograms. Echo facies Type 3 is related to reflection free deposits, commonly associated with muddy beds or fluid muds. Echo facies Type 4 represents rocky beds. These facies are related to different types of seabed and can be used to interpret the main sedimentary processes acting along the bay.
echo facies; sidescan sonar; subbottom profilers
