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  • Weathering processes on rock surfaces in the Hunza Valley, Karakoram, North Pakistan
  • Crystalline rocks ; Duricrust ; Erratic boulder ; Karokoram ; Moraine ; Pakistan ; Valley ; Weathering
  • This paper reports on rock temperature fluctuation in the north and south surfaces of a moraine boulder in Hunza Karakoram obtained over 2 years, and concludes that the rock surface weathering processes depend primarily on the differences
  • of the rock temperatures due to orientation.
  • 1999
  • The effects of fire on rock weathering : some further considerations of laboratory experimental simulation
  • Cyprus ; Experimentation ; Fire ; Geotechnics ; Rainfall simulation ; Rock ; Temperature ; Temperature gradient ; Weathering
  • rock material properties, which can then be related to weathering susceptibility. A range of rock types were collected from the island of Cyprus. The rate of rock disintegration and effects such as case-hardening appear to be a function of rock thermal
  • 1999
  • Chemical erosion ; Geochemistry ; Island ; Japan ; Microstructure ; Mineralogy ; Porosity ; Rock ; Rock mechanics ; Volcanic rock ; Weathering
  • To examine the mechanism of rock-strength reduction due to weathering, temporal changes in microstructure of 4 porous rhyolite were investigated at Kozu-shima Island in the western Pacific. With the results of mineralogical investigations
  • and laboratory tests of pore structure of the rocks, the AA. conclude that the microstructural changes due to chemical weathering strongly influence the reduction of rock strengths.
  • 1999
  • Rites et musiques en Chine - Le rock de Pekin (1991 et 1992)
  • Pekin - Chine - Asie orientale - Asie - Rock - Sociologie - Culture, arts et loisirs - Chine
  • 1999
  • Experimental salt weathering of limestones in relation to rock properties
  • Carbonate rock ; England ; Experimentation ; France ; Geophysics ; Limestone ; Mesozoic ; Portugal ; Salt ; Simulation ; United Kingdom ; Weathering
  • ; assessment of the importance of modulus of elasticity and other factors in affecting durability; and assessment of the use of impulse excitation techniques to monitor changes in rock modulus of elasticity. The rocks showed a wide spectrum of durabilities.
  • 1999
  • Pseudomorphic transformation of plagioclases during the weathering of granitic rocks in Galicia (NW Spain)
  • Microscopic study of twelve weathering profiles developed on granitic rocks in Galicia (NW Spain) showed that, in most cases, the transformation of the parent rock into saprolite occurs with pseudomorphic alteration of the plagioclases
  • 1999
  • The role of thermal stress fatigue in the breakdown of rock in cold regions
  • Antarctica ; Building materials ; Cold area ; Fracture ; Freeze-thaw cycle ; Geotechnics ; Impact ; Radiation ; Rock ; Temperature ; Weathering
  • Recent geomorphological studies have shown the importance of thermal stress in cold regions by means of high-frequency rock temperature data which can identify rates of temperature change in excess. The occurence of weathered material in cold
  • 1999
  • Movement of King's Throne rock glacier, Mount Rae area, Canadian Rocky Mountains
  • Canada ; Cold area ; Geodesy ; Glacier advance ; Mountain ; Rock glacier ; Rocky Mountains
  • 1999
  • Concentrated flow erosion rates as affected by rock fragment cover and initial soil moisture content
  • Concentrated flow experiments using a small hydraulic flume and a constant flow discharge and bed slope have been conducted in order to investigate the effects of rock fragment cover (Rc) on sediment yield for an initially wet and an initially air
  • 1999
  • The effects of grain abrasion and disaggregation on 137 Cs concentrations in different size fractions of soils developed on three different rock types
  • of disaggregation and grain abrasion on the distribution of 137 Cs with respect to particle size fractions were studied in soils derived from the 3 different rock types of the Tarago catchment.
  • 1999
  • A note on sand ripples developing in sandstone rock seepages of the Weald, UK
  • Ephemeral sand ripples are described from steep sandstone rock surfaces in the south of England. They are unconsolidated or stabilized by algae and bryophytes. The sand is transported by flowing water to produce a semi-regular pattern of sinuous
  • 1999
  • The frequency and magnitude concept in relation to rock weathering
  • ) and their effectiveness in terms of rock breakdown, and secondly in terms of the totality of weathering and its effectiveness in terms of larger-scale geomorphological change.Finally, the importance of the ideas of frequency and magnitude as applied to weathering
  • 1999
  • Engineering geomorphology of rock glaciers
  • Alps (The) ; America ; Aquifer ; Classification ; Earth surface processes ; Europe ; Geotechnics ; Mass movement ; Meltwater ; Mountain ; Natural hazards ; Rock glacier
  • 1999
  • Chemical erosion ; Electron microscope ; Eruptive rock ; Geochemistry ; Japan ; Lithology ; Mineralogy ; Shikoku ; Weathering
  • In order to clarify the formative processes of weathering rinds, the AA. accumulate the data on changing in rock properties, such as mineralogical, mechanical, chemical and physical properties through fresh zone to weathering rind. From this point
  • of view, this paper examines the relationships between rock properties of weathering rinds using sanukitoid-andesite as an example.
  • 1999
  • Talus fabric in Tuckerman Ravine, New Hampshire : evidence for a tongue-shaped rock glacier
  • Cirque ; Erratic boulder ; Moraine ; Mountain ; New England ; Palaeogeography ; Rock glacier ; Sedimentology ; Slide rocks ; Slope deposit ; United States of America
  • 1999
  • Alluvial fan and catchment initiation by rock avalanching, Owens Valley, California
  • The North Long John alluvial fan of the Inyo Mountains piedmont, Owens Valley, was catastrophically initiated by a prehistoric (early Holocene?) rock avalanche. The key implication of this study is that not all fans of a particular piedmont
  • are of the same longetivity or stage of development. This study also points out that the geological hazards on the piedmont beneath triangular bedrock facets (rockfalls, roskslides, and rock avalanches) contrast with the dominantly debris flow or water-flow
  • 1999
  • Measurements of bottom temperature of the winter snow cover (BTS) in relation to rock glacier activity, Corviglia, Swiss Alps : a preliminary report
  • Alps (The) ; Ground survey ; Mountain ; Periglacial features ; Permafrost ; Research technique ; Rock glacier ; Snow cover ; Soil temperature ; Switzerland
  • (MAST) measurement. Rock glaciers are classified into active, inactive, and fossil types in terms of the activity status and the presence of permafrost. In this paper, the activity was tentatively evaluated by vegetation, on the basis of the empirical
  • 1999
  • Rock glaciers in the Pyrenees
  • Europe ; France ; Holocene ; Lateglacial ; Moraine ; Mountain ; Periglacial features ; Permafrost ; Pyrénées ; Rock glacier ; Spain ; Spatial distribution ; Typology
  • 1999
  • Symptoms of degradation in a tropical rock glacier, Bolivian Andes
  • Andes ; Bolivia ; Climatic variation ; Geophysics ; High mountain ; Mountain ; Periglacial features ; Permafrost ; Rock glacier ; Tropical zone
  • 1999
  • Areal distribution of rock glaciers in the Argentera Massif as a tool for recent glacial evolution reconstruction
  • Alps (The) ; Deglaciation ; Glacier ; Italy ; Mountain ; Orographic effect ; Rock glacier ; Spatial distribution
  • 1999