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Restoration of Riparian Ecosystems
Published in Malchus B. Baker, Peter F. Ffolliott, Leonard F. DeBano, Daniel G. Neary, Riparian Areas of the Southwestern United States, 2003
Jonathan W. Long, Alvin L. Medina, James E. Steed
Geology constitutes the genetic material of the watershed and its riparian systems, and its infiuence extends to factors that change at short time scales. Lithology is important, not only because it frequently serves as a proxy for other important variables such as elevation, but also because it infiuences the soil properties, sediment fiows and substrate composition of riparian ecosystems. Topography and exposures of bedrock regulate processes of deposition, erosion, soil formation and groundwater movement. Climate and hydrologic regime determine runoff and basefiow, which in turn infiuence development of soils, channel morphology and vegetation. For example, systems dominated by spring-fiows tend to have more fallen timber, mosses and organic matter.34 The concept of ecoregion serves to classify areas of relatively homogenous vegetation, soils, climate and hydrology;35 however, most mapped ecoregions are too broad to guide site restoration. They are useful, however, for understanding factors that determine the types of riparian systems that can develop.
Applications of visible to near-infrared spectroscopy for downhole fluid analysis inside oil and gas wellbores
Published in P. Dakin John, G. W. Brown Robert, Handbook of Optoelectronics, 2017
Fujisawa Go, Oliver C. Mullins, Yamate Tsutomu
Properties of the rock formation penetrated by a wellbore are first measured by several instrumented tools relying on nuclear, electrical, and sonic measurements. Properties typically measured include formation density, porosity, basic lithology, resistivity, and stress. Then, a fluid sampling program by a formation sampling tool or “formation tester” is planned based on the formation evaluation. The DFA spectrometer instrument is conveyed to a wellbore as a part of formation tester tool by Wireline tool string or LWD tool string.
Causes, Consequences, and Mitigation of Landslides in the Himalayas
Published in Shruti Kanga, Suraj Kumar Singh, Gowhar Meraj, Majid Farooq, Geospatial Modeling for Environmental Management, 2022
Lithology plays an important role in active geomorphological processes such as landslide, as different lithological units have different sensitivity (Bisht et al. 2006; Singh and Devi 2006; Pandey et al. 2008; Naithani and Rawat 2009). Due to the importance of lithology, numerous researchers have used lithology as an input parameter to analyze the landslide susceptibility (Dai et al. 2001; Sarkar and Kanungo 2004; Duman et al. 2005; Lee and Pradhan 2006; Akgun et al. 2008).
Exploring novel hybrid soft computing models for landslide susceptibility mapping in Son La hydropower reservoir basin
Published in Geomatics, Natural Hazards and Risk, 2021
Nguyen Van Dung, Nguyen Hieu, Tran Van Phong, Mahdis Amiri, Romulus Costache, Nadhir Al-Ansari, Indra Prakash, Hiep Van Le, Hanh Bich Thi Nguyen, Binh Thai Pham
Lithology of rocks plays important role in landslide study (Segoni et al. 2020). Lithology represent general physical characteristics (colour, texture, grain size and mineral composition) of rocks. Weathering of rocks, porosity and permeability depends on the lithology of rock strata. Strength of rocks depends on the type of lithology besides other structural conditions. Therefore, lithology map of the study area was generated from the geology map (1:100,000) of the West North map of Vietnam for the model study (Figure 3(j)).
Deformation and fracture of circular tunnels under non-tectonic stresses and its support control
Published in European Journal of Environmental and Civil Engineering, 2022
Shaohua Du, Diyuan Li, Bo Ruan, Genshui Wu, Bao Pan, Jinyin Ma
As shown in Figure 16(a), if the surrounding rock of a tunnel is characterized by an obvious layered structure, then the lithologic soft rock layer will be destroyed first followed by a domino effect on the adjacent rock formation and final failure of the support structure. Further, an asymmetric tunnel instability failure may also be observed.