Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 13 of 13 for “"bed forms"”.
-
Bathymetric evolution of sand bed forms under partially standing waves
… between water waves and a movable sand bed were investigated. Monochromatic and poly- chromatic waves of specified amplitudes and period were generated under cases of weak (R=0.2) and/or strong (R=0.9) reflections. Experiments included one of two mean grain sand sizes (0.2mm and O.mm) to …
-
Flume studies of large-scale cross-stratification produced by migrating bed forms
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Science, 1981.
-
Flume studies on the kinematics and dynamics of large-scale bed forms
Thesis (Sc.D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Science, 1981.
-
A flume study of bed forms in a medium sand as a function of flow velocity
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1991.
-
Effects of rigid stems on sediment transport
… other hand, the presence of vegetation in riverbed modifies flow structure, flow resistance, sediment transport and morphology. Each single modification has been largely studied, but the knowledge on the mutual relationships are still limited. This project faces a part of these still-unknown …
-
Studies of deep-sea sedimentary microtopography in the North Atlantic Ocean
… depth greater than 2000 m) have been formed as bed forms of deep currents. These bed forms, all developed in cohesive sediments, include current ripples (spacings of tens of centimeters, formed transverse to the flow), longitudinal triangular ripples (spacings of meters, formed in sandy muds and …
-
Flow-Transport Modeling and Quantification
… on the flow and sediment transport over bed forms in alluvial rivers (e.g. mean flow field, turbulence, shear partitioning, bed load transport and bed form geometry). Much of this work was either laboratory studies or small scale field investigations. Recently, advance in technology have …
-
Interaction among vegetation and morphology in channelized rivers
The presence of aquatic vegetation on riverbed and embankments influences flow structure and consequently flow resistance, sediment transport, morphology, and ecology. These influences would lead to a hydraulic diversity, which is a key ingredient of physical habitat in streams. According to this …
-
Modelling the morphodynamics of tidal channels
… equations and the continuity equation for the bed evolution in order to point out the main characteristics of the phenomenon. Numerical results show that the behaviour is non-linear also for relatively small values of the ratio between tidal amplitude and mean flow depth. The morphodynamic …
-
Impacts of vegetation-generated turbulence on sediment transport
… or not. Second, the impact of vegetation on the bed load transport rate was explored. A system that allows sediment to be bypassed, a cart to distribute sediment, a method that measures the dry weight of wet sand without drying the sediment, a topography system, and an sediment trajectory imaging …
-
A Generalized Log-Law Formulation For a Wide Range of Boundary Roughness Conditions Encountered in Streams
… roughness elements comprised of mobile bedforms. The method resulted in similar values of normalized zero-plane displacement for all roughness types considered. The ratios of zero-plane displacement, dh, to roughness height, ks, were 0.20 and 0.26 for the sediment- and vegetation-scale …
-
Transport Processes along Riverine Environments and their Impact on Microplastics
… (i.e. sedimentation and burial into the stream bed) balance the resuspension. The transport scenario analyzed in the first part focuses on floating MP. The second part extends the advection-dispersion model by exploring a different scenario in which the complex dynamics of sedimentation, burial, …
-
Geology, hydrology and hydrogeochemistry of the West Brush Creek Development Area, Beulah Mine, Mercer County, North Dakota
… Paleocene Sentinel Butte Formation were described and correlated. They are, from oldest to youngest, the Spaer, Beulah-Zap, Schoolhouse and Twin Buttes intervals, each named for the lignite bed which caps the interval. The pore-water chemistry of the elastic sediments within these intervals was …