Sediment mass transport from the Squamish River delta into the adjacent fjord (Howe Sound, British Columbia) is dominated by discrete turbidity current events which have incised semi-permanent channels on the delta front and out onto the prodelta. Acoustic data were collected in the spring of 2013, including both active and passive systems. Data from the active sonars are used to determine flow speed, flow thickness and suspended sediment concentration. The noise generated by these discrete turbidity currents is broadband (10 to 200 kHz) and, based on the sediment grain size and flow speeds, is shown to be due to sediment-generated noise, most likely at the base of the flows.

Noise from turbidity currents flowing down the face of a fjord delta was measured underwater at frequencies from 1 to 1200 kHz. The noise spectra are consistent with sound generation by collisions among sand-sized particles. The spectra from the leading head extend to higher frequencies than those from the trailing body, indicating that collisions were between finer-grained particles in the head and coarser-grained particles in the body. Noise intensity increased 100-fold for a two-fold increase in head speed, consistent with the expected collision rate for granular materials in the high-flow gas-like phase and highly turbulent particle-laden flows.

Casing inspection logs may be used to interpret the nature of a casing failure downhole. This paper provides data to improve interpretation for casing failures and presents results of laboratory tests of four commercially available tools. The tools are tested in five casing specimens, corresponding to five types of failures.Results indicate that although standard casing inspection logs can detect the existence of a casing failure in a well and define its location, interpretation of additional details with regard to the type of failure requires special efforts. Calibration procedures and interpretation techniques that are not commonly practiced in the field are presented to allow distinction between a split and a part and to define details of the split or part. Also, recommendations are made with regard to running speeds and'sensitivity settings.

In late 2011 more than 4.2 million cubic meters of seafloor sediments dredged from the central channel of Sydney Harbour (Nova Scotia, Canada) were relocated to a coastal site near Edwardsville, on the west side of the South Arm of the Harbour. Dynamic penetrometer measurements were carried out in October 2012 for rapid geotechnical characterization, localization and quantification of dredged material deposits, using the lightweight dynamic penetrometer Nimrod. Complementary sediment samples and digital images were taken at selected positions using a small grab sampler and underwater camera. Sydney Harbour is characterized by a large variety of sediment types. Muddy sediments ranging from low to moderate consolidation states were found, as well as compacted fine sands. The dynamic penetrometer results allowed the localization and quantification of deposited dredge disposal material in a cost-and time-efficient manner. The spatial distribution of sediments is in good agreement with a sediment dynamics model by CBCL Limited. However, the deposited sediment layers were thicker than anticipated, being on the order of 10-20 cm, and reaching several tens of centimeters when mixed with finer, muddy deposits.

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