湘桂黔滇藏红色岩溶风化壳发育模式   总被引：11，自引：0，他引：11  

李德文  崔之久  刘耕年 《地理学报》2002,57(3):293-300

基于对湘，桂、黔，滇，藏等地岩溶区红色风化壳的野外和室内研究，从表生地貌学，粘土矿物学和地球化学角度分析红色石灰土性质与地貌演化的关系，提出红色岩溶风化壳发育的二阶段模式；1）地貌夷平-风化物质积累阶段，在地貌演化过程中溶蚀残余物质不断积累，最后在夷平面上形成厚层连续的泥质风化壳，夷平面的地貌水文条件有利于粘粒的形成和保存，但限制了富铝化作用的有效进行，造就了岩溶风化壳粘粒含量高，富铝化程度低的特点，这与研究区23个红色岩溶风化壳剖面化学，粒度特征和粘土矿物组合特点一致。2）地貌切割-风化壳淋溶阶段，原始夷平面上的风化壳大多呈灰色，只有在构造隆升和地表微切割导致地下水位降低，淋溶条件开始改善的情况下，风化壳才有可能枞根本上转为红色。  相似文献   

Aspects of dinantian sedimentation in the edale basin,north derbyshire     

Peter Gutteridge 《Geological Journal》1991,26(3):245-269

The Dinantian Edale Basin is located to the north of the Derbyshire carbonate platform and underlies the Upper Carboniferous of the central Pennines. The Edale Basin was thought to be part of a large basin which extended from the Derbyshire carbonate platform to the Askrigg Block. The presence of aggregate grains and ooids in the Alport Borehole suggests that a carbonate platform, possibly located on the Holme structural high, was present underneath the central Pennines. This platform is called the Holme Platform. The Arundian to early Asbian section of the Alport Borehole represents deposition of resedimented shallow-water carbonates with occasional bioturbated periplatform carbonates and basinal shales on the middle part of a carbonate ramp. Volcaniclastic sediments may have been derived from a volcanic centre within the Edale Basin. A change in sedimentation during the mid-Asbian to the deposition of basinal shales and distal carbonate turbidites is attributed to starvation of the basin. This may have been caused by a combination of the development of accretionary rimmed carbonate shelves and the repeated emergence of shelf carbonates deposited on surrounding carbonate platforms. The late Asbian/early Brigantian section of the Edale Borehole is interpreted as a distal equivalent of the ‘Beach Beds’ which outcrop at the north margin of the Derbyshire carbonate platform. The ‘Beach Beds’ represent bioclastic turbidites derived from the Derbyshire carbonate platform. Throughout the Brigantian, sedimentation in the Edale Basin was dominated by the deposition of distal carbonate turbidites and basinal shales. Variation of dip through the Alport Borehole indicates the common occurrence of slumps throughout the sequence and the presence of either an angular unconformity or a fault within the early Brigantian section.  相似文献   

The Distribution of Chadian and earliest Arundian strata in North Wales: Implications for Dinantian (Carboniferous) lithostratigraphy and palaeogeography     

J. R. Davies  N. J. Riley  D. Wilson 《Geological Journal》1989,24(1):31-47

The late Chadian Foel Formation, previously thought to be confined to the Dyserth area of North Wales, forms a poorly exposed but persistent basal unit to much of the Dinantian crop east of the Clwydian Range, necessitating a revision of the local lithostratigraphy. The formation comprises a peritidal heterolith which, together with the lowest few metres of the overlying Llanarmon Limestone, yields microfossil assemblages diagnostic of the Eoparastaffella Cf4α Subzone. Succeeding strata, containing the lowest archaediscid foraminifera, provide the first record of Cf4β assemblages from North Wales and establish an early Arundian age for these beds. The Foel Formation was deposited as an aggradational sequence on the northern flank of St. George's Land during a pulsed transgression which began in late Chadian times. The widely recognized basal Arundian transgression is represented by the contact between the Foel Formation and overlying platform carbonates. The latter overlap the Foel Formation in the southernmost part of the Clwydian crop demonstrating, for the first time, southwards onlap on the northern side of the Bala–Bryneglwys Fault System.  相似文献   

Cryptic exposure horizons in the Carboniferous Limestone of Portishead,Avon     

T. J. Faulkner  V. P. Wright  C. Peeters  L. Garvie 《Geological Journal》1990,25(1):1-17

Two unusual subaerial exposure horizons containing fibrous columnar calcite crystals are described from the (early Chadian) Lower Carboniferous of Portishead, near Bristol in southwest Britain. The lower horizon overlies the Courceyan Black Rock Limestone (mid-ramp facies) and is separated from the upper horizon by the Sub-Oolite Bed and is overlain by the Chadian Gully Oolite (both are inner ramp deposits). Regionally the Portishead Palaeosol Beds are interpreted as forming part of extensive emergent surfaces which developed along the southern margin of the Welsh–Brabant Massif. They correlate with similar subaerial exposure horizons in Belgium and southern Germany, and may be the product of a proposed major eustatic sea level fall at the end of the Courceyan.  相似文献   

The carboniferous lithostratigraphy of Southeast County Limerick,Ireland, and the origin of the shannon trough     

Peter Strogen 《Geological Journal》1988,23(2):121-137

The Carboniferous succession in southeast County Limerick, on the southeastern margin of the Shannon Trough, is Courceyan to mid-Namurian in age and over 1900 m thick. The lithostratigraphy is described in detail. Its most important aspect is the presence of two thick volcanic sequences, a Chadian one of the alkali basalt to trachyte suite and one of Asbian age dominated by limburgites and ankaramites. The associated Dinantian carbonates are of shelf or ramp facies throughout, and no fundamental division into shelf and basin facies occurs as in the Dublin and Craven Basins in early Viséan times. Rapid differential subsidence between this area and the Shannon Estuary began during deposition of the late Courceyan to early Chadian Waulsortian facies but was less marked in the remaining Viséan when much of the volcanic topography was preserved by rapid basinal subsidence. There was basinal inversion in the late Dinantian to lower Namurian, followed by renewed subsidence in mid-Namurian times. This contrasts with the continuous rapid subsidence of the area further west on the Shannon Estuary. This behaviour, together with a comparison of that of nearby Carboniferous basins such as the Dublin, South Munster, and Craven Basins, which lack substantial volcanic sequences, suggests an origin in a transtensional regime rather than one of simple crustal stretching.  相似文献   

The Courceyan stratigraphy of the Pallaskenry Borehole,County Limerick,Ireland     

Ian D. Somerville  Gareth L. I. Jones 《Geological Journal》1985,20(4):377-400

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Discovery of Arundian and Holkerian faunas from a Dinantian platform succession in North Wales     

Ian D. Somerville  Angela R. E. Strank 《Geological Journal》1984,19(2):85-104

For the first time Arundian and Holkerian faunas have been recognized from the lower part of the Dinantian succession in North Wales. These limestones and sandstones, hitherto regarded as Asbian, have a macrofauna and microfauna confirming their older age, and this discovery' has necessitated a revision of the palaeogeography in the North Wales region. Biostratigraphical correlations have been made with contemporaneous platform successions in the Central, Northern, and Southwest Provinces of Britain. A new genus and species of foraminifer, Groessensella moldensis, is described.  相似文献   

Miocene shallow-water limestones from São Nicolau (Cabo Verde): Caribbean-type benthic fauna and time constraints for volcanism     

Daniel Bernoulli  Lukas Hottinger  Silvia Spezzaferri  Peter Stille 《Swiss Journal of Geoscience》2007,100(2):215-225

Shallow-water limestones of presumed Late Cretaceous and Eocene age, interbedded with basaltic lavas, were described by earlier authors from São Nicolau in the northwestern part of the Cabo Verde archipelago. If confirmed, these ages would imply late Mesozoic shallow-marine and subaerial volcanic activity in the Cabo Verde archipelago, and document a geological history very different from that known so far from other Cabo Verde Islands, from which no subaerial volcanic activity before the mid-Cenozoic is known. Our re-investigation of the foraminiferal fauna indicates a Late Miocene age for the presumed Late Cretaceous and Eocene limestones. The hypothesis of a long-lived hot spot, active by the Early Cretaceous, and of a major island-building stage in the Cabo Verde Islands during this period, is therefore not supported by the present bio- or chronostratigraphic data.  相似文献   

A study of the serpentinisation in the Vempalle dolomitic limestones near Pulivendala,Cuddapah District   总被引：1，自引：0，他引：1  

A. N. Vyasa Rao  M. S. Murty 《Journal of Earth System Science》1980,89(1):17-22

The calcite-dolomite ratio of the Vempalle dolomitic limestones, serpentinised dolomitic limestones, and serpentines from the mineralised zone of the asbestos is determined by infrared spectroscopy. The ratio varies between 2 and 5·4 in the dolomitic limestones, between 1 and 1·5 in the serpentinised dolomitic limestones and it is taken as zero in the serpentines as both calcite and dolomite bands are absent in their infrared absorption spectra. The release of calcite during the serpentinisation is identified, which confirms the formation of serpentine.  相似文献   

The Middle and Upper Devonian in southeastern flank of the Siberian platform (Southern Verkhoyansk Region,Sette-Daban Mountain Range)     

V. V. Baranov 《Stratigraphy and Geological Correlation》2007,15(5):470-484

Data on Middle and Upper Devonian deposits studied in southeastern flank of the Siberian platform are considered. A scheme of stratigraphic zoning in the study region is presented. Nineteen sedimentological and biotic events, which are recorded in the studied sections, are of the regional, interregional and global ranks. Their connection with eustatic sea-level fluctuations is established. Sections of the formation and regional horizon stratotypes and parastratotypes are described. The revision of species Mucrospirifer novosibiricus (Toll) is carried out.  相似文献