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131.
This chapter provides a lithostratigraphic correlation and the present knowledge of the depositional history of the Tertiary succession of the Scandinavian countries. The succession records an initial phase of carbonate deposition in the early Paleocene. This was succeeded by deposition of deep marine clays with intercalation of sand-rich mass-flow deposits during most of the Paleocene and Eocene. Volcanic activity in the North Atlantic was extensive at the transition from the Paleocene to the Eocene resulting in widespread sedimentation of ash-rich layers in the North Sea area. During the Oligocene, the first prograding deltaic complex developed, sourced from the Fennoscandian Shield. Late Oligocene-Early Miocene inversion and uplift of Norway and the Shetland Platform resulted in major progradation of coastal and delta plain systems. At the end of the Tertiary most of the North Sea basin was filled and the Fennoscandian Shield was flanked to the west by a broad, coalesced coastal plain.  相似文献   
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The neritic waters of the state of Sergipe in Northeastern Brazil is adjacent to the main nesting area of the olive ridley sea turtles (Lepidochelys olivacea) in the Western Atlantic Ocean and an important area for shrimp trawl fishery. To address the problem of incidental mortality of sea turtles captured during trawling and reduce the risk of overexploitation of shrimp stocks, Projeto TAMAR/ICMBio, a Brazilian sea turtle conservation program, has adopted two main strategies: (1) the implementation of a marine monitoring program and (2) active participation in local forums. This paper describes the conflicts among stakeholders, the arrangements and established mechanisms of negotiation aimed to protect sea turtles and shrimp grounds, and strategies to reduce conflicts between user groups. The analysis of this co-management process highlights the importance of stakeholder participation in resource management decision-making through a cooperative process, the role assumed by non-governmental organizations as mediators, and the factors that influence this system. The key factors and actions learnt from the current study include clear identification of the conflicts, identification of stakeholders – both local and external, and local leaders, encouragement of actors and leaders to participate, support and strengthening of local groups, legitimization of the discussion forums through involvement with government, formalization of decisions taken through legislation, and monitoring of the management efficacy.  相似文献   
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It is generally supposed that specific sediment yield declines as the drainage basin area increases, as part of the mobilized sediment becomes trapped in the downstream cascade of storage zones. In British Columbia, using fluvial suspended sediment load data, Church and Slaymaker (Nature 1989, Vol 337, pp. 452–454) have observed a pattern of increasing specific sediment yield at all spatial scales up to 3×104km2. This trend has been attributed to the dominance of secondary remobilization of Quaternary sediments over primary denudation of the land surface. Using a larger data set of lake sediment-based estimates of long-term sediment yield, sub-regional patterns of specific yield have been investigated for the Canadian Cordillera. Between spatial scales of 0.9 and 190 km2 sediment yield trends are differentiated by physiography, as indicated by the variable allometry observed in the specific sediment yield–drainage basin area relations. Highest sediment yields were observed in the Coast Mountains where specific sediment yields conform to the regional pattern described by Church and Slaymaker. However, in flat-lying plateau and major valley areas specific sediment yield decreases with increasing drainage area, thus conforming to the conventional model of sediment delivery. In several other sub-regions of intermediate relief there were no significant relations between specific yield and drainage area. These results suggest that no single model of sediment yield is adequate to describe sediment transfer processes in the Canadian Cordillera at the sub-regional scale.  相似文献   
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Zusammenfassung Im Unterperm bildet sich mit den küstennahen Innenschelf-Sedimenten der Unteren Pseudoschwagerinen-Kalke (UPK) und über der klastischen Fazies der im hochenergetischen Intertidal-Subtidal-Grenzbereich entstandenen Grenzlandbänke (GB) die Karbonatplattform der Oberen Pseudoschwagerinen-Kalke (OPK) heraus. Ökologische Zonenfolgen, die eine zunehmende Verschiebung zu küstenferneren Bereichen anzeigen, weisen die OPK als Ablagerungen des subtidalen Außenschelf-Bereiches aus.Verschieden alte Schelfrandriffe (Karnische Alpen, Sextener Dolomiten) und die Klastischen Trogkofelschichten als Innenschelfentwicklung im E und SE setzen die Entwicklung der Plattform in der Trogkofelstufe fort.Bodenunruhen mit Brekzienbildungen in den Klastischen Trogkofelschichten gipfeln in einem Zerbrechen der Karbonatplattform an der Wende Unter/Mittelperm und führen zur Ablagerung der Tarviser Brekzie in lokalen Senken.Mit den im W zunächst noch kontinentalen, in den Karnischen Alpen und Westkarawanken aber überwiegend marinen Grödener Schichten und den bei fortschreitender Transgression abgelagerten Bellerophonschichten setzt der alpidische Sedimentationszyklus ein.
Paleontological and sedimentological data of Permian rocks from the Carnic Alps and its neighbouring areas south of the Periadriatic Lineament could fit to the following paleogeographical patterns:The Untere Pseudoschwagerinen-Kalke (UPK) of the Rattendorfer Schichten were cyclically deposited in the inner-shelf area. During the upper UPK erosive activities and source areas of the clastics were changing. Increasing sedimentation of clastics due to the temporary erosion of metamorphic rocks and acid plutonites characterizes the Grenzland-Bänke (GB), deposited in a near-shore high-energy environment with intertidal to subtidal conditions (mega-ripples). The outer shelf sedimentation pattern of the Obere Pseudoschwagerinen-Kalke (OPK) is indicated by special associations of organisms in subtidal offshore areas.On this carbonate platform some knoll reefs of different age were built up during the Trogkofel stage (Carnic Alps, Sextener Dolomiten). Towards the east and southeast the platform shows again characteristics of the inner shelf (Klastische Trogkofel-Schichten).Synsedimentary tectonic activities during the late Lower Permian are manifested by the carbonate breccias of the Klastische Trogkofel-Schichten (Garnie Alps, Karawanken, Slovenia). The components of these breccias are dated as Middle Carboniferous to late Lower Permian. A further destruction of the platform at the Lower/Middle Permian boundary results in the sedimentation of the Tarviser Brekzie.The alpidic cycle Starts with the sedimentation of the clastic Grödener Schichten which during the first phase of sedimentation were deposited as continental clastics in South Tyrol but as predominately marine sediments in the Carnic Alps and in the Karawanken.The increasing transgression during the Upper Permian results in the deposition of bituminous sediments and basal evaporites of the Bellerophon-Schichten. In the south-western near-coast area the evaporites are dominating (facies fiammaza) whereas in northeastern South Tyrol gypsum with open marine carbonates prevails (facies badiotica). The Bellerophon-Schichten of the Carnic Alps indicate connections with the marine Zazar-Schichten in the Save area and with the limestones and dolomites of the Velebit mountains.

Résumé L'étude paléontologique et sédimentologique du Permien des Alpes carniques et des régions septentrionales, voisines du linéament périadriatique, a permis d'en tracér une equisse paléogéographique. - Les Untere Pseudoschwagerinen-Kalke (UPK) qui marquent le début des Rattendorfer Schichten, constituent une sédimentation cyclique de nature littorale, à laquelle succède, à la suite d'une activité érosive intense, les Grenzlandbänke (GB) caractérisés par un facies clastique de haute énergie, avec, dans ce dernier, des intervalles où apparaissent des roches métamorphiques et des roches plutoniques acides. Ce milieu, parcouru par des courants instables, nous indique un domaine mitoyen» subtidal-intertidal «(méga-ripples), à labase des marées. Des faunes et flores, variées et abondantes, sont distribuées dans une succession de zones écologiques de plus en plus distantes de la côte. Les Obere Pseudoschwagerinen-Kalke (OPK), déposés ensuite, se sont donc formés sur le plateau continental extérieur à caractère subtidal.Sur cette plate-forme à formations carbonatées, et au cours de l'étage de Trogkofel, des récifs ont pu s'installer, tandis que l'E et le SW de la plate-forme, plus rapprochés de la côte, ont reçu une sédimentation clastique (Klastische Trogkofelschichten). — Les mouvements de la fin du Permien inférieur se sont traduits par des brèches intercalées dans les Klastische Trogkofelschichten; des fragments de roches du Carbonifère moyen (étage de Moscow) sont inclus dans ces brèches. Enfin cette tendance arrive à son comble à la limite Permien inférieur/Permien moyen, lorsque la plateforme se désintègre avec formation de la Taviser Brekzie dans des effondrements local.Le cycle de sédimentation alpin débute par les Grödener Schichten — encore terrestres à l'Ouest, mais surtout marines dans les Alpes carniques et les Karawanken occidentales — et par les Bellerophonschichten marquant une mer en transgression.

, , (GB) , ( ) (UPK). , , , , . — , — , -, . . , . . , — — .
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138.
The Mount Stuart batholith is a Late Cretaceous calc-alkaline pluton composed of rocks ranging in composition from two-pyroxene gabbro to granite. Quartz diorite is most abundant. This batholith may represent the plutonic counterpart of the high-alumina basalt association. A petrogenetic model is developed in which this intrusive series evolved from one batch of magnesian high-alumina basalt, represented by the oldest intrusive phase, by successive crystal fractionation of ascending residual magma. However, the possibility that this intrusive suite originated from an andésite (quartz diorite) parent by fractionation cannot be excluded.Computer modeling of this intrusive sequence provides a quantitative evaluation of the sequential change of magma composition. These calculations clearly indicate that the igneous suite is consanguineous, and that subtraction of early-formed crystals from the oldest rock is capable of reproducing the entire magma series with a remainder of 2–3% granitic liquid. This model requires that large amounts of gabbroic cumulate remain hidden at depth- an amount equal to approximately 8–10X the volume of the exposed batholith. Mass balances between the amounts of cumulate and residual liquid calculated compare favorably with the observed amounts of intermediate rocks exposed in the batholith, but not with the mafic rocks.Mafic magmas probably fractionated at depth by crystal settling, whereas younger quartz diorite and more granitic magmas underwent inward crystallization producing gradationally zoned plutons exposed at present erosional levels.  相似文献   
139.
Modern high accuracy measurements of the non-rigid earth are to be referred to four-dimensional, i.e., time- and space-dependent reference frames. Geodynamic phenomena derived from these measurements are to be described in a terrestrial reference frame in which both space- and time-like variations can be monitored. Existing conventional terrestrial reference frames (e.g. CIO, BIH) are no longer suitable for such purposes. The ultimate goal of this study is the establishment of a reference frame, moving with the earth in some average sense, in which the geometric and dynamic behavior of the earth can be monitored, and whose motion with respect to inertial space can also be determined. The study is conducted in several parts. In the first part problems related to reference directions are investigated, while subsequent parts deal with positions, i.e., with reference origins and scale. Only the first part is treated in this paper. The approach is based on the fact that reference directions at an observation point on the earth surface are defined by fundamental vectors (gravity, earth rotation, etc.), both space and time variant. These reference directions are interrelated by angular parameters, also derived from the fundamental vectors. The interrelationships between these space- and time-variant angular parameters are illustrated in a commutative diagram, tower of triads, which makes the derivation of the various relationships convenient. In order to determine the above parameters from observations using least squares techniques, a model tower of triads is also presented to allow the formation of linear observation equations. Although the model tower is also space and time variant, its variations are described by adopted parameters representing our current knowledge of the earth.  相似文献   
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