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  • In the Stavelot Massif an angular unconformity has been found within the Devillian, the highest part of which is of early Cambrian age. This unconformity is either intra-Cambrian or just at the base of the Cambrian succession. (Les AA).
  • Application of digital elevation and geological data in studies of morphotectonics and relief - a case study of the sub-Cambrian peneplain in south-western Sweden
  • Cambrian ; Geographical information system ; Numerical model ; Palaeogeography ; Palaeogeomorphology ; Peneplain ; Sweden ; Tectonics
  • This paper aims to apply high resolution digital elevation and geological data, as well as GIS and geostatistics, in order to describe the fragmentation and the gross morphological features of a restricted part of the sub-Cambrian peneplain
  • Geochemical soil surveys over Cambrian and lower Devonian formations in the Belgian Ardennes as a tool for geological mapping
  • High-level plateaus of the southeastern Beartooth Mountains, Montana and Wyoming remnants of an exhumed sub-Cambrian marine plain
  • Vaasan Soderfjärden sedimenttiaineksen suojaama kambrikaudella muodostunut kraatteri. (Soderfjärden, Vaasa, western Finland: a crater covered with sedimentary material since its formation in the Cambrian)
  • The Soderfjärden crater has a diameter of 5-6 Km and its maximum depth exceeds 300 m in a peripheral ring which is covered with Lower Cambrian sedimentary rocks more than 200 m thick. Firm evidence of the process that formed the crater has been
  • difficult to find, as the meteorite-impact features are rather weak and there is no lava that might indicate a volcanic explosion. The rapid filling of the crater may be interpreted as favouring the theory that it originated under a shallow Cambrian sea
  • The Stavelot Massif from Cambrian to recent. A survey of the present state of knowledge
  • The aim of this study is to describe the gross morphology of the joint-aligned valley landscape, trace the sub-Cambrian peneplain as far as possible in the summits, ascertain the present elevated areas and investigate the cause of fragmentation
  • of the sub-Cambrian surface westwards.
  • Speleogenesis of an exhumed hydrothermal sulphuric acid karst in Cambrian carbonates (Mount San Giovanni, Sardinia)
  • Cambrian ; Carbonate ; Cave development ; Hydrothermal ; Italy ; Karst ; Mine ; Mineralogy ; Sardegna
  • A combined geomorphological and mineralogical investigation has permitted a fairly detailed reconstruction of the various phases of evolution of these caves in Sardinia. Cave formation had already started in Cambrian times, but culminated
  • in the Carboniferous, when most of the large voids still accessible today were formed. A key role in carbonate dissolution was played by sulphuric acid formed by the oxidation of the polymetallic ores present in the rocks since the Cambrian. During the Quaternary
  • Isotopic evidence for glacial meltwater recharge to the Cambrian-Ordovician aquifer, north-central United States
  • The chemistry of water in the Cambrian-Ordovician aquifer in six midwestern states has been studied as part of the Northern Midwest Regional Aquifer-System Analysis of the US Geological Survey. The differences in isotopic ratios between groundwater
  • Palynology of uppermost Proterozoic and lowermost Cambrian formations, central Mackenzie Mountains, northwestern Canada
  • Stratigraphy and sedimentology of the Hamill Group in the northern Selkirk Mountains, British Columbia : evidence for latest Proterozoic - Early Cambrian extension tectonism
  • A palaeokarst of probable Kainozoic age preserved in Cambrian marble at Cemaes Bay, Anglesey, North Wales
  • Landforms are used as analytical tools to separate inherited features from the glacial impact on Precambrian basement rocks in southwest Sweden. The study covers 3 different palaeosurfaces, the sub-Cambrian peneplain with the character
  • of a pediplain, an uplifted and dissected part of the sub-Cambrian peneplain, and an etching surface presumably sub-Mesozoic. The surfaces were recently re-exposed, probably due to a Neogene upheaval with some pre-glacial reshaping. This study aims at evaluating
  • The AA. study two weathering profiles, one developed at the head of the pediment, on granodiorites, and the other in the interior of the « Montes de Toledo », on a basement of cambrian slates. Both profiles appear fossilized by the « Raña
  • Two sets of denudation surfaces have been delimited, the exhumed and the epigene ones. The sub-Cambrian peneplain is still of importance for the highest surface, and tilted tectonic blocks can be defined with reference to it. Its limit to the south
  • has been constructed for the southern part of the area. Exhumed sub-Cambrian, sub-Jurassic and sub-Cretaceous inclined surfaces are cut by more horizontal surfaces at different levels.
  • Several occurrences of metamorphosed pre-Hercynian volcanic rocks crop out in the Paleozoic basement of Southern Sulcis (SW Sardinia), hosted in Cambrian-Early carboniferous sedimentary sequences belonging to two different structural units. - (NF)
  • Lower Paleozoic (Cambrian, Ordovician), Devonian, and Carboniferous sedimentary rocks are exposed in the northeastern part of the Hohes Venn area (Northern Eifel) and in its northern forelands. The regional geological development represented
  • Some recent borings N.E. of Tiège cut an important thrust fault with overlapping of the Cambrian on the Eodevonian. The authors describe from the cores the dip and strike of the fracture and the characteristics of the thrust zone proper. (LW).
  • Arctic Region ; Cambrian ; Carbonate rock ; Coastal environment ; Fjord ; Lithostratigraphy ; Ordovician ; Palaeogeography ; Palaeozoic ; Platform ; Stratigraphy ; Svalbard
  • descriptions of some of the existing units are presented. The new lithostratigraphical unit : a Lower(?) to Middle Cambrian Black shale and limestone unit is proposed informally. In addition, a Middle(?) Cambrian to Lower Ordovician Dolostone-limestone unit