The geology and geophysics research group operates three labs focusing on the study of coastal and shelf sea hydrodynamics and sediment dynamics.
The Sediment Analysis Lab is equipped with a range of tools used to analyse cohesive and non-cohesive sediment samples, including particle size distribution, grain texture and composition, and bulk sample properties. These include standard sieve shakers, wet and dry sieves, pump-filtration kits, a sonic bath, drying ovens and a furnace to examine organic content, a unique settling column used to measure particle settling rates and grain size distribution, and a Laser Coulter Sizer used to determine size distribution of fine sediment and particles.
The Coastal Processes Lab hosts a unique suite of annular flumes, and is home to the Lab Carousel (D = 2m, channel: 0.15m wide x 0.5m deep); used to examine sediment dynamics, sediment interaction with biota, including seagrasses and aquatic vegetation, as well as biogeochemical processes. This salt- or fresh-water flume/meso-cosm can accommodate a range of high-frequency instruments, including a custom-built acoustic Doppler velocimeter (ADV) and electromagnetic current meters (EMCM) to measure flow and turbulent properties, with built-in optical backscatter sensors and water sampling ports to determine suspended sediment concentrations. Its acrylic design allows the use of Laser anemometry and (video-) cameras can be installed to observe sediment transport and bedform dynamics. Hot film probes can be flush-mounted to the flume base for direct measurement of shear velocity through constant-temperature anemometry.
A field-going, benthic annular flume, with matching dimensions, can be deployed in the field to examine similar processes over natural, undisturbed beds subjected to controlled hydrodynamic forcing. A range of smaller ‘mini’ annular flumes can be used for smaller-scale experiments, or in the field/ aboard research vessels to conduct similar experiments into erosion and deposition thresholds of fine sediments, and including directly over 30cm diameter or larger box cores.
The Coastal Dynamics Lab hosts a 7m x 0.3m x 0.45m long recirculating, tilting flume (Armfield S6) used to study velocity profiles and boundary layer dynamics, turbulence and drag over rough boundaries, including vegetated and mobile sediment beds under unidirectional currents. It can also accommodate an oscillating cradle to simulate oscillatory/combined wave current flows typical of coastal and continental shelf waters.
A scour flume (5m x 0.6m x 0.6m) is used to study sediment transport and scour evolution around (partially or fully) submerged structures including bridge piers, wind turbines, and archaeological artefacts such as ship wrecks.
A counter-rotating annular flume allows the study of transport process at high speeds, such as those typical of submarine gravity flows. This is equipped with an ultra-high concentration meter (UHCM) and an ultrasonic Doppler velocity profiler (UDVP) to measure velocities and concentrations at high sediment loads.
A small wave tank (2m x 0.15m x 0.3m) can be used to demonstrate wave transformation in shallow waters, beach profile evolution, and bedform morphology under surface gravity waves. Two small racetrack demonstration tanks and a stream table are additionally used to teach fundamental principles of sediment transport, including threshold of motion, bedroom dynamics, and morphodynamics of rivers, deltas and intertidal mudflats.
A range of standalone and live-logging instruments are also available for lab and field deployments. These include point-wise and profiling Nortek acoustic Doppler Velocimeters (vectrino and vectorino II), a wide range of pressure gauges and transducers (PT), conductivity, temperature and depth probes (CTD), stream flowmeters, optical backscatter sensors (OBS), high speed video-cameras, strain gauges and hot-film probes. We also have a number of integrated Valeport 808 units (OBS, EMCM, PT), modified benthic and epi-benthic Helley-Smith sand traps, a cohesive strength meter, a sediment imaging sonar (SIS), sector scanner and side scanning sonars. We have also developed a set of GPS-enabled Lagrangian Drifters for use in Rip current research; Eromes, a benthic erosion chamber used to investigate bed stability on the small scale; and the high resolution benthic roughness acoustic device (BRAD) used to construct 3D volumetric, acoustic scans of bed roughness (mm scale) and suspended particles in the water column.
For further information, contact Dr Hachem Kassem
