Photograph of a paper recorder which provides a hardcopy of the sonar return from the R/V Thompson's 3.5 kHz sub-bottom profiler. This relatively low frequency sonar penetrates the upper sedimentary strata below the surface of the seafloor, providing a cross sectional picture of seafloor sediments, underlying rock outcrops, and faults. The paper record shown here presents a cross-sectional image of Daisy Bank highlighting the Bank's steep south-facing wall (horizontal lines mark 25 meter depth intervals). This image of Daisy Bank shows an enigmatic rim encircling the top of the Bank. Historical submersible dives on Daisy Bank by Oregon State University scientists have shown that the flanks of the Bank support a rich and diverse fauna of sessile invertebrates, including gorgonian corals and sponges (some quite large). Image courtesy of Lewis And Clark Legacy Expedition, NOAA-OER.
