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Impact of subsurface rock fragments on runoff and interrill soil loss from cultivated soils
  • Impact of subsurface rock fragments on runoff and interrill soil loss from cultivated soils
  • Belgium ; Cultivated land ; Erosion rate ; Experimentation ; Infiltration ; Rainfall simulation ; Rill wash ; Rock fragment ; Soil erosion ; Soil properties ; Splash ; Water erosion
  • In this study interrill laboratory experiments with simulated rainfall for 60 min were conducted to assess the influence of subsurface rock fragments incorporated in a disturbed silt loam soil at different depths below the soil surface
  • , on infiltration, surface runoff and interrill erosion processes for small and large rock fragment sizes. Although only small differences in infiltration rate and runoff volume are observed between the soil without rock fragments (control) and the one
  • with subsurface rock fragments, considerable differences in total interrill soil loss are observed between the control treatment and both contrasting rock fragments sizes. This is explained by a rapid increase in soil moisture in the areas above the rock fragments
  • and therefore a decrease in topsoil cohesion compared with the control soil profile. The results highlight the impacts and complexity of subsurface rock fragments on the production of runoff volume and soil loss and requires their inclusion in process-based
  • 2011
Holocene chemical weathering, surface lowering and rock weakening rates on glacially eroded bedrock surfaces in an alpine periglacial environment, Jotunheimen, southern Norway
  • Holocene chemical weathering, surface lowering and rock weakening rates on glacially eroded bedrock surfaces in an alpine periglacial environment, Jotunheimen, southern Norway
  • In this paper, new indices of rock surface weakening (IRW) and the rock surface weakening rate (WR) are defined in relation to Schmidt hammer mean R-values for gneiss and peridotite. The methods and results are evaluated, particularly in relation
  • to previous research and other rock types in Scandinavia. The various indices, being affected in different ways by biochemical and biological mechanical weathering and micro-erosion, are regarded as complementary aids in the investigation of both the effects
  • 2011
Air circulation in deep fractures and the temperature field of an alpine rock slope
  • Air circulation in deep fractures and the temperature field of an alpine rock slope
  • Air circulation ; Alps (The) ; Fracture ; Mountain ; Rock ; Rockfall ; Slope dynamics ; Switzerland ; Temperature ; Thermal regime ; Water circulation
  • In this study, the AA. address the impact of air and water fracture flow on the temperature field of an alpine rock slope at 2400 m a.s.l. in southern Switzerland. They first approximate the conductive temperature field based on distributed
  • measurements, highlighting deep steady temperatures and different transient effects. Then they discuss observations and mechanisms of convective disturbances by both air and water flow in deep fractures, and conclude by commenting on implications for rock slope
  • 2011
A regional inventory of rock glaciers and ice-cored moraines in Norway
  • A regional inventory of rock glaciers and ice-cored moraines in Norway
  • Classification ; Inventory ; Mountain ; Norway ; Periglacial features ; Permafrost ; Rock glacier ; Spatial distribution
  • In total 307 permafrost landforms have been mapped, consisting of rock glaciers and ice-cored moraines. The landforms were classified as active/inactive (intact) or relict landforms, and by origin. In northern Norway, permafrost landforms exist down
  • to sea level and the majority of the landforms are relict talus-derived rock glaciers. In southern Norway, permafrost landforms are restricted to high elevations and the majority of the landforms are connected to glacial activity and classified as active
  • 2011
Kontaktni kras v Kočevskem Rogu in Kočevski Mali gori
  • Carbonate rock ; Karst ; Karstification ; Slovenia ; Typology
  • recognized: between non-carbonate and carbonate rocks and between different carbonate rocks. In the first case, ponors and blind valleys were formed and concave forms near the contact are infilled with non-carbonate sediments. On the contact between different
  • carbonate rocks the forms are similar but less evident, e.g. ponors, ponor steepheads and dry valleys. - (IKR)
  • 2011
Numerical modelling of combined erosion and weathering of slopes in weak rock
  • Numerical modelling of combined erosion and weathering of slopes in weak rock
  • Due to various decay processes associated with weathering, the stability of artificial slopes in weak rocks may be affected well within their envisaged engineering lifetime. This paper combines two conceptual models for erosion and weathering
  • , and derives a numerical model which predicts the resulting slope development. This can help to predict the development of a slope profile excavated in a weak rock in time, and can be extended with the addition of strength parameters to the weathering profile
  • 2011
Two large late Quaternary rock slope failures and their geomorphic significance, Annapurna Himalayas (Nepal)
  • Two large late Quaternary rock slope failures and their geomorphic significance, Annapurna Himalayas (Nepal)
  • This paper is a contribution to the knowledge of large-scale landslides in the Nepal Himalaya. The A. presents two examples of giant rock slope failures that occurred north of the Annapurna Range, namely the Manang rock avalanche and Thini debris
  • 2011
Unraveling driving factors for large rock–ice avalanche mobility
  • Unraveling driving factors for large rock–ice avalanche mobility
  • Avalanche ; Climatic change ; Glacial features ; High mountain ; Mass movement ; Model ; Mountain ; Natural hazards ; Periglacial features ; Rock glacier ; Slope dynamics
  • This contribution is an attempt to unravel driving factors for the mobility of large rock-ice avalanches by synthesizing results from physical laboratory experiments and empirical data from 64 rock-ice avalanches from glacierized high mountain
  • critical factors. The results provide an empirical basis to roughly account for different path and flow characteristics of large rock-ice avalanches and to find appropriate ranges for friction parameters for scenario modeling and hazard assessments.
  • 2011
Internal structure of the Green Lake 5 rock glacier, Colorado Front Range, USA
  • Internal structure of the Green Lake 5 rock glacier, Colorado Front Range, USA
  • Climatic change ; Colorado ; Geophysics ; Ground penetrating radar ; Hydrology ; Model ; Mountain ; Periglacial features ; Rock glacier ; Seismic method ; United States of America
  • Three different geophysical techniques (shallow seismic refraction, ground-penetrating radar (GPR) and electrical resistivity tomography)were used to develop a detailed subsurface model of the Green Lake 5 rock glacier in the Colorado Front Range
  • , USA. Results and discussion. The model of the internal structure was used to evaluate an existing hydrological flowpath model based on the hydrochemical properties of water outflow from the rock glacier. In conclusion, the AA. discuss the implications
  • 2011
Spatial distribution of rock fragments on steep hillslopes in karst region of northwest Guangxi, China
  • Spatial distribution of rock fragments on steep hillslopes in karst region of northwest Guangxi, China
  • The objective of this paper was to investigate the relationship between the spatial distribution of rock fragments and landforms on two different steep karst hillslopes in northwest Guangxi, southwest China. The results suggested that rock fragment
  • content within the topsoil was primarily controlled by slope position and gradient and had not a close relationship with the presence of large rock outcrops. Such information is crucial for understanding and modeling the spatial variation
  • 2011
Spatial characterization of salt accumulation in early stage limestone weathering using probe permeametry
  • Carbonate rock ; Geochemistry ; Permeability ; Porosity ; Salt ; Simulation ; Spain ; Spatial variation ; Statistical analysis ; Weathering
  • Variations between the permeability properties of fresh rock and the same rocks after the early stages of a salt weathering simulation are used to examine the effects of salt accumulation on spatial variations in surface rock permeability properties
  • of permeability and to correlate these changes with salt movement, porosity change, potential rock deterioration and textural characteristics. Statistical analyses of small-scale permeability measurements are used to evaluate the drivers for decay and hence aid
  • 2011
Field observations of infragravity waves and their behaviour on rock shore platforms
  • Field observations of infragravity waves and their behaviour on rock shore platforms
  • in water level at the cliff toe during high tide. Results from this study show the first measurements of IGWs on shore platforms and identify long wave motion a significant process in a morphodynamic understanding of rock coast.
  • 2011
How many colours have those black rock mountains ?
  • How many colours have those black rock mountains ?
  • In Uyghur Turkic language, Karakorum roughly means “black crumbling rocks” (kara = black; korum = gravel). But there are in fact many more colours than just black in the Karakorum mountains. Three of them are red, white, and green. These three
  • 2011
Intrusion of mafic magmas into felsic magma chambers : new insights form natural outcrops and fluid-mechanics experiments
  • Fractals ; Geology ; Geophysics ; Igneous rock ; Magma ; Rheology ; Rock
  • ratio between magmas towards low values and, hence, towards the best rheological conditions to trigger widespread mixing processes in the magma chamber. In conclusion, the present paper shows that combining fractal geometry measurements on natural rocks
  • 2011
Advective heat transport in frozen rock clefts : conceptual model, laboratory experiments and numerical simulation
  • Advective heat transport in frozen rock clefts : conceptual model, laboratory experiments and numerical simulation
  • Climatic change ; Crack ; Experimentation ; Heat transfer ; Meltwater ; Model ; Mountain ; Numerical model ; Periglacial features ; Permafrost ; Rock ; Rockfall
  • affect failure planes beneath large rock masses and failure events could therefore differ greatly from common magnitude reaction-time relations.
  • 2011
Practicing physical geography : an actor-network view of physical geography exemplified by the rock art stability index
  • Practicing physical geography : an actor-network view of physical geography exemplified by the rock art stability index
  • Arizona ; Concept ; Epistemology ; Pedagogy ; Rock art ; Stability index ; United States of America ; Weathering
  • This paper explores the use of a new pedagogy, the rock art stability index (RASI), to engender deeper understanding of weathering science concepts by students. Using concept maps as an assessment tool, 571 college undergraduate students and 13
  • 2011
The use of the Schmidt Hammer and Equotip for rock hardness assessment in geomorphology and heritage science : a comparative analysis
  • The use of the Schmidt Hammer and Equotip for rock hardness assessment in geomorphology and heritage science : a comparative analysis
  • The AA. review here the capabilities of 2 types of Schmidt Hammer (Classic N type and Silver Schmidt BL type) alongside 2 types of Equotip (standard type D and Piccolo) for investigating rock hardness in relation to rock weathering on various types
  • 2011
Granite caves in the north-east of the Iberian Peninsula: Artificial hypogea versus tafoni
  • Archaeology ; Catalonia ; Cave ; Crystalline rocks ; Geomorphogenesis ; Geomorphometry ; Granite ; Human impact ; Lithology ; Spain ; Taffoni ; Weathering
  • The origin of eight supposedly artificial caves in granite rocks located in the north-east of the Iberian Peninsula is revised in this work. Although human features are present in four of the caves, they have little morphological significance
  • 2011
Surface and sub-surface Schmidt hammer rebound value variation for a granite outcrop
  • This paper presents Schmidt hammer (SH) measurements on intact and prepared surfaces in the Jizerské hory Mountains, Czech Republic. SH R-values were collected from granite outcrop surfaces and from vertical profiles below rock surface. The main
  • aims of this study were (1) to verify the influence of surface grinding on the results of SH measurements; (2) to uncover how rock hardness changes with depth; and (3) to identify the age limitations of the SH dating technique.
  • 2011
Geological evolution of the Karakoram Ranges
  • and igneous rocks of the lower crust. The Karakoram terrane has been above sea-level since Early to Mid-Cretaceous, the age of the youngest marine sedimentary rocks. Geological and U-Pb geochronological data show that the Karakoram Range was a dynamic active
  • 2011