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On the Specification of the Information Available for the Perception and Description of the Natural Terrain
Published in Peter Hancock, John Flach, Jeff Caird, Kim Vicente, Local Applications of the Ecological Approach to Human-Machine Systems, 2018
Robert R. Hoffman, Richard J. Pike
In their guide to aerial photo interpretation, Rinker and Corl (1984) explicitly acknowledged the role of perception (the visual impression of shape) and experience. Although they too relied heavily on generic terms and descriptors (e.g., closely spaced hills, teardrop-shaped hills, sharply rounded summits, etc.), they attempted some verbal definitions. For example, “basins and valleys are depressions that are sufficiently large to provide a significant separation between adjacent higher elevations” (p. 17). A fault is a “perceptible displacement between the sides of a fracture along the fracture plane, ranging from small cracks to transverse continental lineations” (p. 33). Plains are defined as “any relatively flat surface of sufficient extent to be a mappable unit” (p. 63). Rinker and Corl even offered an occasional definition of a descriptor—lumpiness is “small-(e.g., fine-) scale roundness”. They also provided ostensive definitions—clear-case examples in stereophoto form and profile diagrams, illustrated here in Figure 1.
Wind Energy Resource
Published in D. Yogi Goswami, Frank Kreith, Energy Conversion, 2017
Depressions are characterized by terrain features lower than the surroundings and include valleys, canyons, basins, and passes. These can cause significant speedup of the wind if they effectively channel the wind. The factors that influence the flow in depressions, in addition to diurnal flow variations, include orientation of the wind in relation to the depression, atmospheric stability, the width, length, slope and roughness of the depression, and the regularity of the section of valley or canyon. Canyons in mountainous terrain, such as those illustrated in Figure 7.13, can be very effective in creating high wind speeds.
Petroleum Geological Survey
Published in Muhammad Abdul Quddus, Petroleum Science and Technology, 2021
The formation and alteration of basins (depression) and mountains (uplift) are regular features throughout geological time. There are many geological factors in the creation and modification of basins: Movement of hot and molten magma. The major factor for the creation of a petroleum basin is the deformation of the earth’s crust, due to the underground geological movement of hot and molten magma. The slow movement of the hot magma exerts stress on the above earth crust. The crust tries to adjust itself to the new thermodynamic conditions. Crust basement rock (igneous and metamorphic) is affected by the upward thrust of the magma. The basement rock may compress or expand or protrude into the above sedimentary rock. In the former case a land depression is created that may be filled with water creating a lake or the depression on the land may remain dry. The expansion or protrusion of basement rock into the earth crust and sedimentary rock creates a mountain range by uplifting the surface sediment layer. Subsidence of basement rock. A basin is created by the subsidence (contraction) of igneous or metamorphic basement rock, followed by downward bending (depression) of the earth’s crust. The depression may be filled by sediments and water to form a basin.Folding and faulting. The downward bending of rock is further modified by folding and faulting during sedimentation. Graben basin is formed along one side of the faulting line.Basin modification. Geological compressional forces acting both on the basin and mountain range continue to work during geological time. New mountains and basins are continuously formed with new sediments. Simultaneously erosion and weathering continue to affect and continue to modify the basin and mountain during geological time.Basins are formed in low-lying valley areas not far from mountain ranges. The mountains erode and rain water carries the sediments below to form a new basin.Mountain areas are not fit for petroleum generation. Mountains are fully exposed to atmospheric and climatic conditions. There are greater possibilities of opening, leakage, sliding and loss of deposited matter including oil/gas. They are subjected to weathering and erosion. They cannot preserve and accumulate the organic deposition for a long time, and there is no fresh supply of sediments.
The past, present, and future of blind inlets as a surface water best management practice
Published in Critical Reviews in Environmental Science and Technology, 2020
Chad Penn, Javier Gonzalez, Mark Williams, Doug Smith, Stan Livingston
Drainage of closed depressions is often accomplished using a combination of surface and subsurface (tile) drainage. A surface inlet is typically placed at the lowest elevation within the depression and routes ponded water directly to the subsurface drainage network, whereas subsurface drainage lines aid in lowering seasonally perched water tables. Ponded and subsurface water is subsequently transported via the subsurface drainage network tens to thousands of meters to the nearest drainage ditch. It is estimated that the number of closed depressions with surface inlets in the Western Lake Erie Basin may exceed 75,000 (Feyereisen et al., 2015). In the Minnesota River Basin, more than 250,000 (1–11 per km2) closed depressions are farmed and likely drained (Mueller & Wehrenberg, 1994). Surface runoff draining through the surface inlet to the tile drainage network has the potential to transport sediment, nutrients, and pesticides directly from fields to receiving waters. Research in the St. Joseph River watershed in Indiana demonstrated that the relative area of closed depressions within the watershed was correlated with the amount of phosphorus (P) conveyed to agricultural drainage ditches (Smith et al., 2008). Tomer et al. (2010) also reported that surface inlets contributed 50% of the total P in the Tipton Creek watershed in Iowa.
Impact of climate variability and wetland drainage on watershed response in depression dominated landscapes
Published in International Journal of River Basin Management, 2018
The study area is mainly located in the depression-dominated landscapes of North American Prairies (Figure 1). In this region, numerous depressions, created by the past glaciations, can retain a great deal of water which may or may not be released to contribute to run-off at the outlet of the larger watersheds depending on the climate inputs and the antecedent moisture condition (Stichling and Blackwell 1957, Rosenberry and Winter 1997, Shaw et al.2012, Ehsanzadeh et al.2012a, 2012b). These naturally varying contributing areas are subject to further fluctuations due to a range of human disturbances including ditching practices. The hydrologic response to the anthropogenic activities in this landscape, therefore, is expected to be complex and hard to predict (Sheldon et al.2005, Fang et al.2010, Pomeroy et al.2010).