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The effect of selected physiographic factors on dissolved gypsum transport by simulated runoff on gypsiferous soils
  • The effect of selected physiographic factors on dissolved gypsum transport by simulated runoff on gypsiferous soils
  • In this paper, attention is focused on the following aspects : to determine the role of runoff in the transport of dissolved gypsum, to establish the effect of physiographic factors on the dissolved gypsum yield, to estimate the level of gypsum
  • saturation reached by runoff and to quantify the dissolved gypsum load.
Correlating specific conductivity with total hardness in gypsum karst waters
  • Correlating specific conductivity with total hardness in gypsum karst waters
  • Europe ; Gypsum ; Hydrochemistry ; Karst ; North America ; Poland ; Water
  • The aim of this paper is to evaluate how adequately simple specific electrical conductivity measurements in the field may be used to estimate amounts of dissolved gypsum and total disolved solids in gypsum karst areas. To illustrate the foreign ion
The role of playas in pedogenic gypsum crust formation in the central Namib Desert : a theoretical model
  • The role of playas in pedogenic gypsum crust formation in the central Namib Desert : a theoretical model
  • Aeolian deflation ; Aerosol ; Arid area ; Desert ; Duricrust ; Gypsum ; Namibia ; Pedogenesis ; Playa ; Sebkha
  • The formation of Namibia's extensive pedogenic gypsum crusts is interpreted in a new light. It is suggested that gypsum primarily precipates at isolated points of evaporitic concentration, such as inland playas, and that deflation of evaporitic-rich
  • gypsum dust from these playas contributes to the formation of pedogenic gypsum duricrusts on the coastal gravel plains of the Namib Desert surrounding these playas. This study establishes the nature, extent and distribution of playas in the Central Namib
  • Desert and provides evidence for playa gypsum deflation and gravel plain deposition.
Gypsum karst features as evidence of diapiric processes in the Betic Cordillera, Southern Spain
  • Gypsum karst features as evidence of diapiric processes in the Betic Cordillera, Southern Spain
  • Andalusia ; Diapir ; Doline ; Groundwater ; Gypsum ; Hydrogeology ; Karst ; Mountain ; Salt tectonics ; Spain ; Tectonics
  • The aim of this paper is to integrate the geological and hydrogeochemical data to evaluate the evolution of the gypsum karst in the Triassic evaporite deposits of the Betic Cordillera, taking into account halokinetic processes.
Rillenkarren on gypsum in Nova Scotia
  • Rillenkarren on gypsum in Nova Scotia
  • Canada ; Gypsum ; Karren ; Karst ; Nova Scotia ; Rill wash
The pattern of gypsum transport in the Ebro river network
  • The pattern of gypsum transport in the Ebro river network
  • Results of the study of gypsum transport in the Ebro river basin during the hydrological period 1970-85.
Distribution patterns of gypsum and kalistrontite in a dry lake basin of the southwestern Kalahari (Omongwa pan, Namibia)
  • Distribution patterns of gypsum and kalistrontite in a dry lake basin of the southwestern Kalahari (Omongwa pan, Namibia)
  • Arid area ; Evaporite ; Groundwater ; Gypsum ; Kalahari ; Mineralogy ; Namibia ; Palaeo-environment ; Spatial distribution
  • The studied basin is a pan of the southwestern Kalahari, in eastern central Namibia. The distribution patterns of gypsum and kalistrontite are mainly determined by groundwater depth and by the lithological composition of the deposits. Gypsum occurs
Genesis and evolution of gypsum tumuli
  • Genesis and evolution of gypsum tumuli
  • Almería ; Arid area ; Carbonate dissolution ; Cyclogenesis ; Geochemistry ; Gypsum ; Karst ; Semi-arid area ; Spain ; Tectonics
  • The aim of this paper is to demonstrate that, at least in the case of tumuli developed on macrocrystalline gypsum, the processes of dissolution and reprecipitation within the same gypsiferous layer can produce the observed folding. Furthermore
  • , the AA. wish to deduce the role played by structural controls and the influence of the texture of the gypsum in their formation. Tumuli must be considered as superficial karstic mesoforms, characteristic of certain gypsiferous karstic landscapes in arid
Solution and recrystallisation processes and associated landforms in gypsum outcrops of Sicily
  • Solution and recrystallisation processes and associated landforms in gypsum outcrops of Sicily
  • Climatic geomorphology ; Earth surface processes ; Evaporite ; Gypsum ; Holocene ; Italy ; Karst ; Mediterranean area ; Model ; Sicilia ; Weathering
  • Four small areas of Messinian (Upper Miocene) age gypsum, outcropping in western Sicily, are described. They were specifically chosen to describe a type of medium-sized form : dome-like hills which are covered by a mosaic of smaller forms, related
  • to both categories : different types of karren and of expansion forms. The AA. discuss models of the dynamics of these gypsum outcrops which are illustrated with the support of large scale geomorphological maps.
Recent aeolian origin of surficial gypsum crusts in southern Tunisia : geomorphological, archaeological and remote sensing evidence
  • Recent aeolian origin of surficial gypsum crusts in southern Tunisia : geomorphological, archaeological and remote sensing evidence
  • Aeolian features ; Archaeology ; C 14 dating ; Duricrust ; Eolian deflation ; Geochronology ; Gypsum ; LANDSAT ; Quaternary ; Remote sensing ; Roman era ; Surface deposits ; Thematic Mapper ; Tunisia
  • This paper provides new evidence on both the mode of formation and the age of surficial gypsum crusts by studying archaeological, remote sensing and geomorphological evidence from surficial gypsum deposits in the Chott Fedjaj basin and northern part
  • of the Chott Djerid basin, southern Tunisia. The research focuses on crusts located on and adjacent to glacis near Tozeur, where a Roman site is located near and within an extensive deposit of surficial gypsum crusts.
Gypsum karst and its evolution east of Hafik (Sivas, Turkey)
  • Gypsum karst and its evolution east of Hafik (Sivas, Turkey)
  • Carbonate dissolution ; Doline ; Gypsum ; Karst ; Karstification ; Polje ; Turkey
The micromorphology of gypsum and halite in reg soils - the Negev Desert, Israel
  • The micromorphology of gypsum and halite in reg soils - the Negev Desert, Israel
  • Alluvial cone ; Arid area ; Chronosequence ; Gypsum ; Israel ; Micromorphology ; Negev ; Pedogenesis ; Quaternary ; Reg ; Salt
  • The aim of this paper is to document the changes in the micromorphology of gypsum and halite at different stages of reg soil development on 2 alluvial fan chronosequences. The micromorphological analyses included thin sections observations
The use of gypsum, spheres for identifying water flow routes in soils
  • The use of gypsum, spheres for identifying water flow routes in soils
  • Gypsum has been cast into spheres and placed in soils| weight loss has been used to identify relative water flow routes. Theoretical considerations and laboratory experimentation show that solutional weight loss of the material used increased
  • with increasing water flow, but is independent of pH above pH 4. Results for gypsum sphere weight loss are presented for soils where moisture conditions have been measured independently using tensiometers. The data suggest that the weight loss method provides
The origin of sulphates : an example of sulphur isotopic applications
  • Arid area ; Biogeochemical cycle ; Cold area ; Evaporite ; Geochemistry ; Gypsum ; Human impact ; Isotope analysis ; Palaeo-environment ; Pollution
  • This review is concerned with the technique of stable isotope analysis (δS 34) as a means of studying the sulphur cycle with particular emphasis on the formation of sulphate evaporites such as gypsum. Gypsum is found in all settings that promote
  • evaporation, including hot and cold desert environments. The review features gypsum in caves, salt pans and limestone walls with sulphur sources ranging from the marine environment to bedrock.
THE NEERREPEN SOIL, AN EARLY OLIGOCENE PODZOL WITH A FRAGIPAN, AND GYPSUM CONCRETIONS FROM BELGIAN AND DUTCH LIMBURG
  • THE NEERREPEN SOIL, AN EARLY OLIGOCENE PODZOL WITH A FRAGIPAN, AND GYPSUM CONCRETIONS FROM BELGIAN AND DUTCH LIMBURG
Deep-water gypsum deposits as indicated by the Neogene geological history of the central coastal plain of Israel
  • Deep-water gypsum deposits as indicated by the Neogene geological history of the central coastal plain of Israel
Gypsum formation in non-calcareous building sandstone : a case study of Scrabo sandstone
  • Gypsum formation in non-calcareous building sandstone : a case study of Scrabo sandstone
  • This paper addresses one central issue of building stone research : an origin for calcium in gypsum formation in non-calcareous sandstones. A comparative study of Scrabo sandstone from outcrops and a 120-year-old building in central Belfast shows
  • how weathering has significantly altered the mineralogy. Preliminary results suggest that the occurrence of gypsum throughout the stone blocks is related to chemical reactions between a pore-filling mineral, actinolite, and sulphur oxides from urban
  • pollution. This study highlights the potential for future research into an internal mineralogical source of calcium for gypsum formation in building stones.
Sources of sulphur in gypsiferous sediments and crusts and pathways of gypsum redistribution in southern Tunisia
  • Sources of sulphur in gypsiferous sediments and crusts and pathways of gypsum redistribution in southern Tunisia
  • Arid area ; Biogeochemical cycle ; Duricrust ; Geochemistry ; Groundwater ; Gypsum ; Isotope analysis ; Sedimentary basin ; Sedimentation ; Tunisia
  • This paper aims to assess the utility of sulphur isotope analysis for providing an insight into the source of the gypsum in the vicinity of the Chott Djerid basin, southern Tunisia. The AA. sampled the isotopic composition of bedrock samples
  • , groundwater, playa brines, playa sediments and gypsiferous crusts in order to shed light on the sulphur cycle within the basin, and the processes that lead to gypsum crust formation.
Gypsum karstification induced subsidence: effects on alluvial systems and derived geohazards (Calatayud Graben, Iberian Range, Spain)
  • Gypsum karstification induced subsidence: effects on alluvial systems and derived geohazards (Calatayud Graben, Iberian Range, Spain)
  • Alluvium ; Cenozoic ; Evaporite ; Floodplain ; Graben ; Gypsum ; Karst ; Spain ; Subsidence ; Tectonics ; Zaragoza
The gypsum karst aquifer in Ouled Farès area (northern Algeria)
  • The gypsum karst aquifer in Ouled Farès area (northern Algeria)
  • Algeria ; Groundwater ; Gypsum ; Hydrogeology ; Karst ; Water quality