Die Rheingrabenrandverwerfung im Wattkopftunnel bei Ettlingen (Nordschwarzwald)     

Ernst Neßeler  Michael Fröhler  Sebastían Lebede 《International Journal of Earth Sciences》1993,82(4):765-768

The Wattkopftunnel, near Ettlingen (Nordschwarzwald), drives through the eastern margin of the Rheingraben. The tunnel passes cenozoic and mesozoic sediments. Early quarternary and tertiary beds are situated west of the main thrust of the Rheingraben. Fossil record indicates upper Oligocene age (Chatt) for parts of the tertiary sediments. At the eastern border of the Rheingraben, wedges of jurassic and middle triassic series are squeezed. East of the Rheingraben the tunnel drives in the lower triassic Bausandstein. The eastern margin of the Rheingraben was investigated in detail during tunneling. Faults of the Rheingraben margin are distributed in an 130 meter wide fault zone in the tunnel. Total stratigraphic separation by the normal faults reaches more than 2 000 meters. The cenozoic sequence suffered synsedimentary to early diagenetic deformation, while the mesozoic series are characterized by ruptural deformation. The fault- and joint system is directed in the rheinische Richtung (SSW-NNE). East of the Rheingraben a second direction occur, running parallel to the lower Albtal (W-E).

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New paleomagnetic results from the Aegean extensional province     

Haubold  Herbert  Scholger  Robert  Kondopoulou  Despina  Mauritsch  Hermann J. 《Geologie en Mijnbouw》1997,76(1-2):45-55

Various Oligocene formations from NE Greece (ignimbrites from the Medousa area, rhyolites from Zagradenia, granodiorites from Elatia) show discordant paleomagnetic signatures, in each case indicating small cw (clockwise) rotation and also inclination flattening. Marls from Pithion were partly remagnetized in a present-day field. Samples that contain ancient magnetization components also indicate small cw rotation and inclination flattening. However, the magnetization of andesites from Peplos reflects a considerably larger rotation, likely owing to local tectonics. In the context of previous work in the area, these results are used to propose a subdivision of NE Greece into four structural zones of distinctive rotational behaviour (from east to west): sites in zone 1, east of the Kavala-Xanthi-Komotini fault (KXK), show various cw and ccw (counterclockwise) rotation angles owing to complex kinematics resulting from the interaction of the KXK and the north-Anatolian fault zone. However, zone 2, between the KXK and the Strymon valley, is structurally homogeneous ( 10° cw rotation). The paleomagnetic signature of the Vertiskos massif (zone 3) implies a larger (> 30°) cw rotation, whereas sites in the Vardar basin (zone 4) contain a paleomagnetic signature similar to that of zone 2. This suggests a motion of the Vertiscos massif, a meta-ophiolitic nappe, relative to underlying strata. Indeed, zones 2 and 4 may be parts of the same structural unit which underlies this nappe.  相似文献   

Possible ways to decipher spatial distribution of mineral resources     

V. Nemec 《Mathematical Geology》1992,24(6):705-709

Regularity of structural patterns can be connected to planetary disjunctive systems (paleosystems). A computerized universal model of these systems should be developed that may be helpful to predict unknown localities of mineral resources controlled by tectonic processes. The specific character of tectonic phenomena is to be respected in geomathematical models. Some suggestions for applications are given.  相似文献   

Comparison of structural and least-squares lines for estimating geologic relations   总被引：1，自引：0，他引：1  

Garnett P. Williams  Brent M. Troutman 《Mathematical Geology》1990,22(8):1027-1049

Two different goals in fitting straight lines to data are to estimate a true linear relation (physical law) and to predict values of the dependent variable with the smallest possible error. Regarding the first goal, a Monte Carlo study indicated that the structural-analysis (SA) method of fitting straight lines to data is superior to the ordinary least-squares (OLS) method for estimating true straight-line relations. Number of data points, slope and intercept of the true relation, and variances of the errors associated with the independent (X) and dependent (Y) variables influence the degree of agreement. For example, differences between the two line-fitting methods decrease as error in X becomes small relative to error in Y. Regarding the second goal—predicting the dependent variable—OLS is better than SA. Again, the difference diminishes as X takes on less error relative to Y. With respect to estimation of slope and intercept and prediction of Y, agreement between Monte Carlo results and large-sample theory was very good for sample sizes of 100, and fair to good for sample sizes of 20. The procedures and error measures are illustrated with two geologic examples.  相似文献   

Three-dimensional model and late stage warping of the Plattengneis Shear Zone in the Eastern Alps     

Martin Putz  Kurt Stüwe  Mark Jessell  Philippe Calcagno   《Tectonophysics》2006,412(1-2):87-103

The Plattengneis shear zone is a 250–600 m thick, flat lying, Cretaceous, eclogite facies, mylonitic shear zone, with north-over-south transport direction, that is exposed over almost 1000 km² in the Koralpe region along the eastern margin of the Alps. Although the shear zone is one of the largest in the Alps, its role in the Eoalpine metamorphic evolution and the subsequent exhumation of the region, remain enigmatic and its large-scale geometry is not well understood. The outcrop pattern suggests that the shear zone is made up of a single sheet that is folded into a series of open syn- and antiforms with wavelengths of about 10 km. Eclogite bodies occur above, within and below the shear zone and there is no metamorphic grade change across the shear zone. In the south, the fold axes strike east–west and plunge shallowly to the east. In the north, the fold axes are oriented in north–south direction and form a dome shaped structure of the shear zone. Total shortening during this late stage warping event was of the order of 5%. Indirect evidence constrains this folding event to have occurred between 80 and 50 Ma and the fold geometry implies that the final exhumation in the Koralpe occurred somewhat later than further north. Interestingly, the shear zone appears to strike out of the topography in the south and dip into the topography in the north, so that north of the shear zone only hanging-wall rocks are exposed and south of it only foot-wall rocks. Possibilities for the geometric relationship of the Plattengneis shear zone with the surrounding south dipping detachments are discussed.  相似文献   

Spontaneous Structural Reform in Australian Local Government: the case of the Gilgandra Co-operative Model in New South Wales     

Brian Dollery  Warrick Moppett  Lin Crase 《The Australian geographer》2006,37(3):395-409

Dire financial constraints and the threats of forced structural reform have had the unforeseen effect of forcing municipal councils across Australia to reconsider their operational activities and organisational arrangements. With considerable ingenuity, numerous municipalities have proposed and sometimes adopted new structural formations that embody various forms of co-operative service provision. This remarkable development has unfortunately been largely ignored in the scholarly literature on Australian local government. In a modest effort aimed at remedying this neglect, the present paper seeks to outline the small, rural New South Wales Gilgandra Shire Council's (2004) ‘Co-operative/Local Government Service Company’ model, place it in the broader context of alternative models of local governance suitable for Australian conditions, and evaluate its characteristics.  相似文献   

洪山预测区煤层赋存的可能性分析     

尚洪田 《中国煤田地质》2006,18(4):25-26,52

分析了洪山预测区西部洪山岩体地质特征及其向外围扩散的范围和程度，研究了北掌勘查区和焦窑煤矿两邻区煤层受岩浆岩影响的程度，认为洪山岩体对预测区煤系及煤层赋存的影响较小，岩体外围仍有煤系赋存。为下一步找煤指明了方向。  相似文献   

吾祠煤矿区构造特征及矿井生产布局探讨     

张钦文 《中国煤田地质》2006,18(5):14-16,37

通过对漳平市吾祠煤矿区的煤层地质构造特征分析，探讨了复杂构造条件下的矿井生产布局，主要是煤矿区段水平划分、煤炭采区的巷道布置、采煤方法及有关地质硐探等问题，对矿山开发有一定的指导意义。  相似文献   

An Assessment of Structural Measures for Flood-prone Lowlands with High Population Density along the Keelung River in Taiwan     

Lung-Sheng Hsieh  Ming-Hsi Hsu  Ming-Hsu Li 《Natural Hazards》2006,37(1-2):133-152

Midstream of the Keelung River Basin in Northern Taiwan has become highly urbanized and densely populated area. Flood inundation along riversides frequently occurred during typhoons or rainstorms. Three protection measures, including constructions of high-level protection levees, a diversion channel, and a detention reservoir, were proposed for flood mitigation. The main purpose of this study is to evaluate the flood mitigation performance of the three proposed structural measures by using combined hydrologic analyses and hydraulic routings. A semi-distributed parallel-type linear reservoirs rainfall-runoff model was used for estimating the surface runoff. Furthermore, a 1-D dynamic channel routing model was coupled with a two-dimensional inundation model to simulate the hydraulic characteristics of river flooding and overland flow. Simulation results of flood stages, runoff peak discharges, and inundation extent under design rainfall scenarios were chosen as the criteria for evaluation. The results showed a diversion channel is superior to the other two measures for flood mitigation of the study area. After the process of environmental impact assessment, a revised diversion channel approach has been approved for construction as the major structural measure.  相似文献   

青藏高原北羌塘地区晚三叠世地层展布和沉积型式   总被引：10，自引：3，他引：10  

朱同兴  董瀚  李才  冯心涛  李宗亮  于远山  金灿海  周帮国 《沉积与特提斯地质》2005,25(3):18-23

北羌塘盆地地处拉竹龙-金沙江缝合带和双湖构造混杂岩带之间,自北向南可划分出5个沉积相带/岩石地层单位：以砂泥质复理石-洋岛、岛弧型火山岩-大理岩岩石组合沉积为特征的若拉岗日群,以深水复理石盆地相沉积为特征的藏夏河组,以深水暗色细碎屑岩盆地相沉积为特征的结扎群,以开阔台地相/缓坡相碳酸盐岩沉积为特征的菊花山组,以三角洲相含煤碎屑岩系沉积为特征的土门格拉群.晚三叠世北羌塘盆地显示为南缓北陡的箕状沉积格局,盆地内充填物为南薄北厚的楔形沉积体,且双物源、沉降中心和沉积中心不一致,表明其具有前陆盆地的一系列沉积特征.  相似文献