Quartz microstructures developed during non-steady state plastic flow at rapidly decaying stress and strain rate

Synseismic loading to very high stresses (>0.5 GPa) and subsequent creep during stress relaxation in the uppermost plastosphere at temperatures of ca. 300–350 °C, near the lower tip of an inferred once seismically active crustal scale fault, was proposed based on peculiar microstructures identified in rocks exposed over >100 km² in the Sesia Zone, European Western Alps. Here we discuss the conspicuous and highly heterogeneous microstructural record of quartz in disseminated small-scale shear zones. Sub-basal deformation lamellae and arrays of elongate subgrains on the TEM-scale indicate an early stage of glide-controlled deformation at high stresses. Distributed brittle failure is indicated by healed microcracks. Very fine-grained recrystallised aggregates with a pronounced crystallographic preferred orientation reflect intense plastic flow by dislocation creep. Locally, a fine-grained foam microstructure indicates a final stage of static grain growth at low differential stress. For the previously inferred peak stresses of about 0.5 GPa and given temperatures, initial strain rates on the order of 10⁻¹⁰ s⁻¹ are predicted by available flow laws for dislocation creep of quartz. We emphasise the importance of short-term non-steady state deformation in the uppermost plastosphere underlying seismically active upper crust. The related heterogeneous record of quartz is governed by the local stress history at constant temperature.     

Interwedging and inversion structures around the trans-European suture zone in the Baltic Sea, a manifestation of compressive tectonic phases

During the evolution of continents, compressive tectonic phases can leave certain tectonic patterns in the lithosphere to be observed by reflection seismology. Also, in the area of the trans-European suture zone (TESZ) in the Baltic Sea, several relatively short, but occasionally strong, compressive phases have left their marks in the lithosphere in form of characteristic fault and thrust zones in the rigid parts of crust and mantle, especially clear and well investigated in some sediment troughs. At depth, interwedging processes seem to be generated by colliding tectonic units with different rheology, creating bi-vergent fault structures, possibly—but not necessarily—initiated by a previous subduction of intervening oceanic lithosphere. Near the surface, reactivation and inversion of previous faults are very selective. Transpressional processes and the reduced friction inside the faults are suggested to play a major role. It is assumed that the transfer of plate boundary stressed over long distances is performed mainly through the thick and rigid mantle lid, not through the thin, rigid, and heterogeneous upper crust. This assumption involves mechanisms of a vertical transfer of stresses from the mantle into the inversion area, and some signs of such a process are seen around the Tornquist Zone (TZ). Several examples of compressive transfer of stresses are shown.     

新桥硫铁矿伴生金银赋存状态及分布规律

系统阐述了新桥矿伴生金银的赋存状态和分布规律 ,对综合利用矿产资源 ,提高金银的回收率 ,以及深部资源预测、外围找矿均具有一定的指导意义     

Local state restructuring and urban transformation in post-apartheid Cape Town

This paper analyzes processes of state restructuring at the scale of the local state and the city, exploring the social and political relationships generated through processes of reconstruction specifically in Elsies River, a formerly segregated `coloured' neighborhood in Cape Town. While the relationship between Elsies River residents and the local state has been characterized by an obsessive focus on housing debt, I examine the ways in which antagonism over housing problems overlie a broader relational disjuncture between neighborhood and state political and social networks. The specificity of this case provides a lens onto the ways in which processes of state restructuring both contest and reinforce racial, economic, and place-based inequalities in South African cities. The paper concludes by using the complexities of local state-neighborhood relationships in the South African case to reflect on geographical theories of state-society relations on a conceptual level. This revised version was published online in July 2006 with corrections to the Cover Date.     

按分量加权的探测目标状态线性融合

给出了一种在使残差方差矩阵的迹最小化意义下的状态估计线性组合的最优融合准则和加权矩阵的计算公式，并给出了利用实际数据计算的试验结果。结果表明，利用本方法使融合后的目标轨迹与目标真实运动轨迹非常接近，能有效地提高雷达情报的综合质量。     

近百年武汉市主汛期降水特征分析

本文对武汉市1906-2000年主汛期（6-8月）的降水量资料进行了分析。结果表明，近百年来武汉市有两个旱涝事件多发时段，出现在30年代中期以前和60年代以后，主汛期降水量气候基本态在20世纪经历了高、低、高、低、高5个阶段，目前处于高基本态高变率时段，还利用小波变换揭示出了武汉市近百年来主汛期降水的多时间尺度特点，分析了其主要周期振荡和突变特征，指出武汉市主汛期降水存在40年、25年、10年、4-7年左右的周期振荡，并由降水的周期性推知本世纪初武汉市汛期将进入下一个少雨时段。     

Focal Fault and Stress Field of the Yao‘ an M 6.5 Earthquake on January15,2001

Using the 78 focal mechanism solutions of the fore shocks, main shock and after shocks of the earthquake sequence for the Yao'an earthquake, the characteristics of the focal faults and stress field for the earthquake sequence are analyzed. The results show that the main rupture plane of the Yao'an earthquake sequence is a tectonic fault with N50°W strike and steep dip and all the main shock, the fore shocks and the vast majority of after shocks occurred on the main rupture plane. A tectonic fracture with NNE-NE strike also participated in development process of the sequence. The focal stress field of the sequence dominated by principal compressional stress with nearly horizontal orientation SSE is consistent with the regional tectonic stress field. In the sequence development, the stress field in the focal region was complex with multi-azimuths and multi-action models and the focal rupture showed complex features with multi-directions and multi-patterns.     

Néotectonique affectant les dépôts marins tyrrhéniens du littoral sud-est tunisien : implications pour les variations du niveau marin

Pleistocene marine deposits of so-called Tyrrhenian age in southeastern Tunisia include two lithostratigraphic units of Last Interglacial (marine isotopic substage 5e). The lower unit culminates at about +3 m above the sea level; the upper unit with Strombus bubonius culminates at +5 m. Brittle deformations affected the upper unit. The analysis of fault-slip data sets reveals a post-Tyrrhenian N020°E trending compression, consistent with joint patterns. This event induced limited vertical movements, showing that at the northeastern edge of the Saharan Platform, the coastal area of the southern Tunisia remained relatively stable since at least the Last Interglacial.     

土体中的第四纪断层结构面特征及其地震和岩土工程意义

将土体中的第四纪断层作为一种土体结构面，已成为岩土工程新的研究领域，通过对土体断层面上物质特征的研究，发现当断层面上土颗粒的定向度大于80％，且有次生矿物生成时与蠕滑有关；当定向度小于80％，无次生矿物生成时与粘滑有关。     

Biophysical impacts of climate change on bird populations and migration in Lithuania

This paper presents data obtained from studies of the dependence of different migratory processes - spring arrival, migratory take-off, spring and autumn en route migration–upon climate change in Lithuania. The article confirms the impact of global climate warming on different breeding bird species and populations, changes in their ranges and population state, and their staging and wintering areas. The list of bird species which are shifting their ranges north-eastward or eastward in the Baltic region under the influence of global warming is presented. It was established that the impact of global climate change upon birds of terrestrial and wetland complexes is more evident than upon waterfowl. Attention is focussed on the practical importance of the global climate change impact on environmental protection and different branches of the economy. This revised version was published online in July 2006 with corrections to the Cover Date.