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1.
The British Geological Survey has recently re-mapped the Isle of Wight at a scale of 1:10,000. This has added to a wealth of geological research already published. Within this paper, we highlight the importance of geology to the heritage of the Isle of Wight and its impacts on everyday life. There is a growing cultural awareness of the variety of landscapes and resources, the geology that underpins them, and the need to manage and understand them in a sensitive and sustainable way. ‘Geodiversity’, which collectively embraces these themes, is defined as “… the natural range (diversity) of geological (rocks, minerals, fossils), geomorphological (land form, processes) and soil features …” (Gray, 2004). This paper will focus on the geomorphological features; that is, the link between geology, the landscape it influences, and the human interactions with it. Examples from the Isle of Wight of the influences of geology on landscape include the landslides at Ventnor; geotourism at The Needles, Alum Bay and various dinosaur sites; and the artificial landscapes resulting from resource extraction. The geological issues and examples that we have used are some of the most applicable to everyday life, and therefore ones that many people will be able to relate to, such as geohazards (e.g. landslides), water supply, economic value (e.g. quarrying) and tourism. The paper is aimed at the non-specialist and students but also may provide a contextual element to professionals.  相似文献   

2.
The Monk's Bay Sandstone Formation (MBSF) is the new name for the Lower Albian ferruginous sandstone that was formerly known as the Carstone of the Isle of Wight. The new term was proposed to remove any confusion with the Carstone, of similar age and lithology, described from the separate Lower Cretaceous sedimentary basin of Eastern England. This paper formalises the nomenclatural change outlined in the Lower Cretaceous Framework Report, ratified by the Geological Society Stratigraphy Commission.The MBSF, representing a major mid-Albian transgressive event, is described from a series of boreholes drilled by the British Geological Survey across the Isle of Wight, and from additional coastal exposures, together with reinterpretations of sections described in earlier works.The age range of the MBSF is determined in relation to recent biostratigraphical schemes supported with new data from the previously unknown presence of foraminifera. Deposits, belonging to the Leymeriella regularis Subzone, were previously considered to be absent from the succession and represent the stratigraphical gap separating the formation from the underlying Sandrock Formation. However a first occurrence of tubular foraminifera resembling Hyperammina/‘Rhizammina cf dichotomata’ suggest that the oldest part of the formation in the northeast of the island may be of regularis Subzone age. This unconformity is correlated with the sequence boundary LG4 of Hesselbo and the presence of the Sonneratia kitchini Subzone at the base of the MBSF on the Isle of Wight suggests that this boundary should be placed at the lower of two candidate horizons within the successions of the Weald.The formation is restricted to the Isle of Wight but is coeval with similar coarse-grained sediments, e.g. the Carstone and ‘JunctionBeds’ to the north. The palaeogeography of the formation and the relationship with these similar deposits and the implications for the timing of mid-Albian structural events is briefly discussed. The identification of older Lower Greensand Group sediments beneath the MBSF in boreholes north of the Isle of Wight structure, together with new survey data indicating north-south orientated faulting affecting the early Cretaceous implies a tectonic element to the distribution the Lower Greensand Group sediments. Taken together these imply a complex interaction of tectonics and transgressive events throughout the Aptian and Albian over this structural high.  相似文献   

3.
The Wealden Beds (non-marine Lower Cretaceous) of the Wessex Sub-basin, southern England, are exposed principally in coastal sections on the Isle of Wight and in Dorset. Geological Conservation Review sites within these strata have been extensively documented since the earliest days of geological enquiry in Great Britain. The succession is dominated by the alluvial Wessex Formation which demonstrates a broad east–west transition from meanderplain lithofacies to coarser-grained alluvial sediments, in relative proximity to the Cornubian source massif. The meanderplain sediments on the Isle of Wight are of international importance for their plant and animal fossils, the latter including many dinosaurs and their trackways. Upper Barremian transgression resulted in the spread of muddy lakes and coastal lagoons from the Weald Sub-basin into the eastern part of the Wessex Sub-basin, around or through the Purbeck–Isle of Wight structure. The resulting richly fossiliferous mudrock-dominated strata are now represented by the Vectis Formation on the Isle of Wight and in Swanage Bay, Dorset. The Geological Conservation Review sites in the Wessex Sub-basin are documented and interpreted, with particular reference to research history, chronostratigraphy, structural context, palaeoenvironments, palaeobiology and palaeoclimatology. New directions for research are proposed, as applicable.  相似文献   

4.
The charm of the Isle of Wight, so much appreciated by visitors and the local population alike, is very much a combination of its delightful scenery and unique assemblage of vernacular buildings. These buildings range from isolated farmhouses to elaborate manor houses, castles and churches all constructed using the indigenous stone resources of the island. Today, these stone buildings, many of which date back to medieval times, are increasingly in need of conservation repair to maintain them for future generations. Essential to such conservation work is the safeguarding of the island's indigenous building stone sources as many of the stones used are unique to the island and no longer quarried. Protecting these stone sources could also provide stone for new building projects which would help to further enhance the character of the island's towns and villages.  相似文献   

5.
6.
Rebbachisauridae is a poorly understood clade of diplodocoid sauropod dinosaurs, currently known only from the Cretaceous of Africa, Europe and South America. European representatives are particularly rare and fragmentary. Here, we report an anterior caudal vertebra from the Barremian (Early Cretaceous) Wessex Formation of the Isle of Wight, off the southern coast of England. This specimen possesses several features known only in rebbachisaurids and shares two synapomorphies with the Afro-European taxa Demandasaurus darwini and Nigersaurus taqueti, both pertaining to the morphology of the neural spine. These features are the development of triangular lateral processes and the presence of an elliptical fossa on the lateral surface, bounded by the lateral lamina and postspinal rugosity. The Isle of Wight specimen also shares several features solely with Demandasaurus, indicating a close relationship with the Spanish taxon. These include the presence of a hyposphenal ridge, as well as an anteriorly excavated caudal rib that is restricted almost entirely to the neural arch. However, it differs from Demandasaurus in a number of ways, including the lack of excavation on the posterior surface of the caudal rib, the orientation of the neural spine, and the composition and morphology of the lateral lamina. In addition, the Isle of Wight vertebra possesses one potential autapomorphy: bifurcation of the elliptical fossa on the neural spine. However, because of the fragmentary nature of the material, a new name is not erected. Along with Demandasaurus and Histriasaurus boscarollii, this caudal vertebra indicates the presence of at least three European rebbachisaurid taxa and provides new anatomical information on this enigmatic clade of sauropod dinosaurs.  相似文献   

7.
《Cretaceous Research》2012,33(6):774-780
Rebbachisauridae is a poorly understood clade of diplodocoid sauropod dinosaurs, currently known only from the Cretaceous of Africa, Europe and South America. European representatives are particularly rare and fragmentary. Here, we report an anterior caudal vertebra from the Barremian (Early Cretaceous) Wessex Formation of the Isle of Wight, off the southern coast of England. This specimen possesses several features known only in rebbachisaurids and shares two synapomorphies with the Afro-European taxa Demandasaurus darwini and Nigersaurus taqueti, both pertaining to the morphology of the neural spine. These features are the development of triangular lateral processes and the presence of an elliptical fossa on the lateral surface, bounded by the lateral lamina and postspinal rugosity. The Isle of Wight specimen also shares several features solely with Demandasaurus, indicating a close relationship with the Spanish taxon. These include the presence of a hyposphenal ridge, as well as an anteriorly excavated caudal rib that is restricted almost entirely to the neural arch. However, it differs from Demandasaurus in a number of ways, including the lack of excavation on the posterior surface of the caudal rib, the orientation of the neural spine, and the composition and morphology of the lateral lamina. In addition, the Isle of Wight vertebra possesses one potential autapomorphy: bifurcation of the elliptical fossa on the neural spine. However, because of the fragmentary nature of the material, a new name is not erected. Along with Demandasaurus and Histriasaurus boscarollii, this caudal vertebra indicates the presence of at least three European rebbachisaurid taxa and provides new anatomical information on this enigmatic clade of sauropod dinosaurs.  相似文献   

8.
陡倾层状岩质斜坡易产生倾倒变形,在山区可见大量由倾倒变形发展形成的大型滑坡,研究其形成机制对于正确评价边坡稳定性具有重要意义。本文以皖南山区阳台滑坡为例,在工程地质勘察的基础上,采用定性分析、二维离散元和有限元相结合的方法,详细研究了阳台滑坡的变形破坏过程及其影响因素。研究结果表明,阳台古滑坡的形成包括河流下切岩体卸荷回弹、倾倒变形逐步发展、滑面发展整体破坏、堆积体次级变形4个阶段。这类滑坡的防治应重点控制滑坡前缘的变形,并做好截排水工作。  相似文献   

9.
This paper presents a detailed numerical study of the retrogressive failure of landslides in sensitive clays. The dynamic modelling of the landslides is carried out using a novel continuum approach, the particle finite element method, complemented with an elastoviscoplastic constitutive model. The multiwedge failure mode in the collapse is captured successfully, and the multiple retrogressive failures that have been widely observed in landslides in sensitive clays are reproduced with the failure mechanism, the kinematics, and the deposition being discussed in detail. Special attention has been paid to the role of the clay sensitivity on each retrogressive failure as well as on the final retrogression distance and the final run‐out distance via parametric studies. Moreover, the effects of the viscosity of sensitive clays on the failure are also investigated for different clay sensitivities.  相似文献   

10.
A datum, marked by the first appearance of plaktonic species, is described from the London Clay of Whitecliff Bay and Alum Bay, Isle of Wight. Its value in the correlation of Lower Eocene sections in the Hampshire Basin is discussed.  相似文献   

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