Menzies and Hess (3) Flashcards
De Geer moraine
A term derived from Sweden that can also be used to describe cross-valley, Rogen, and ribbed moraines that are typically subglacially squeezed forms.
De Kalb mounds
These are found in the mid-west USA, a term to describe a series of subglacially squeezed moraines.
Equifinality
A term used to convey the fact that many landforms or bedforms, although of different origins and with differing sediment contents, may end up looking remarkably similar in the final form.
Equilibrium
It is the altitude on an ice mass that marks the point below which all previous year’s snow has melted. This lower zone, of course, marks the Zone of Ablation, and the upper zone is the Zone of Accumulation on an ice mass.
Erosivity
A term used to indicate the susceptibility of bedrock or sediment to erosion.
Grounding-line
As ice masses approach open water, whether an ocean or a large lake, the ice due to buoyancy will begin to lift off its solid bed and float. The point in the terrain where this occurs is the grounding-line.
Me ́lange
A term used to express the generally vast
variations in sediment content found within landforms and bedforms within glacial environments, especially those derivative of the subglacial and proglacial environments.
Polar ice mass
This term is used to refer to those ice masses that exist below the pressure melting point, in other words, ice masses that are frozen to their beds and in which there is no free meltwater at their base.
Rogen moraine
These morainal forms, in the past termed ribbed, washboard, and cross-valley moraines, are formed transverse to the dom- inant ice flow directions
Sediment rheology
This refers to the deformability of a sediment in terms of its plasticity or otherwise generally as a function of particle size, porewater content, and impact of the stress applied.
Temperate ice masses
This is commonly termed warm- based or wet-based ice mass – this term is used to refer to those ice masses that exist at or above the pressure melting point, in other words, ice masses that are not frozen to their beds and in which there is free meltwater at their base.
The transport of sediments within the glacial system requires an appreciation of…
cascading sediment delivery systems (SDS) in supraglacial, proglacial, and subglacial subenvironments.
Sediment delivery occurs as a function of…
Ice dynamics, the type of ice mass, basement and subjacent geology and sedimentology, the temporal and spatial variability of sediment discharge (flux), associated hydrological regimens, and topography.
In terms of ice dynamics and its influence on sediment transport, each local SDS depends on…
ice internal and basal thermal conditions whether polar or temperate.
What conditions transports the most sediment in alll SDS subsystems?
Temperature wet conditions
