黏性土的应力-应变关系归一化性状探讨

土的应力-应变关系与固结压力水平密切相关,体现为土的归一化性状.针对黏性土固结不排水剪切试验的应力-应变关系,对黏性土归一化性状的存在条件进行了探讨分析,认为黏性土应力-应变关系归一化性状的存在与否取决于土的模量与归一换化因子的正比关系及土的抗剪强度特性,通常采用围压σ3和平均固结压力σm作为归一化因子;研究表明当应力-应变关系为Kondner双曲线方程形式,对于采用围压σ3和平均固结压力σm归一化效果很差的黏性土,若采用(σ3)n或(σm)n(选取适当的n值)进行归一化,则效果较好.     

岗曲河混凝土面板堆石坝三维静力应力变形分析

采用邓肯模型对岗曲河面板堆石坝进行了三维有限元分析,研究软岩填筑层对坝体工作性能的影响,计算混凝土面板与岩石填筑层的位移和应力及周边缝变形。结果表明,由于受到下游堆石3D软岩填筑区的影响,坝体最大横断面最大沉降略偏向下游,总沉降量约为坝高的0.2 %,面板周边缝位移的绝对值一般都小于2 cm,周边缝的止水设计需注意选择合理的止水形式和填缝材料,由于坝址河谷狭窄,受岸坡约束,三维效应对坝体的应力变形影响较明显,为设计施工提供了参考。     

鄂尔多斯块体周缘地区近期地震活动性与汶川地震应力触发作用的关系

采用β统计对汶川地震前后鄂尔多斯块体周缘地区的地震活动率进行了空间扫描分析,并采用JiChen的震源破裂模型计算了汶川地震产生的库仑破裂应力变化,以研究鄂尔多斯块体周缘地区近期地震活动性与汶川地震应力触发作用的关系。结果发现,鄂尔多斯块体西南缘弧形断裂束的南东段与南缘渭河盆地的地震活动率在汶川地震后提高显著,其他区域的地震活动率没有明显提高,库仑破裂应力计算得到两个区域的应力变化范围分别为0.005～0.02 MPa和0.001～0.01 MPa,表明汶川地震有可能触发了这两个区域的地震活动。鄂尔多斯块体东缘的山西断陷带处于库仑破裂应力计算的应力增加区,应力变化范围为0～0.012 MPa,2009年3月以来发生的4次ML4.5～5.2级强有感至微破坏地震有可能被汶川地震所延迟触发。b值、地震能量释放率与空间相关距离SCL等地震活动性参数随时间变化扫描结果显示,该区域可能处于不断趋近高应力累积的状态,其未来大震有可能提前发生。西缘地区为应力减小区,其目前的地震活动处于正常水平状态。     

Peripheral challenge in container port system: A case study of Pearl River Delta

The growth of peripheral ports to dominant hubs has been well documented in North America and Europe,and has led to the elaboration of several theoretical models.However,although changes in containerization growth have been taking place in the South and East Asia in recent years,particularly in China,only a few studies have fo-cused on this region.The Pearl(Zhujiang) River Delta(PRD) has a typical port system with hub and peripheral ports,and provides an excellent case for studying the Peripheral Challenge.This paper introduces the theoretical evidence of the Hayuth model and analyzes the evolution of the container port system in the PRD with five phases:1) phase I:preconditions for change and phase II:initial container port development in the 1970s and early 1980s;2) phase III:diffusion,consolidation,and port concentration in the middle and late 1980s;3) phase IV:the load center in the 1990s;and(4) phase V:the Peripheral Challenge since the late 1990s.The results illustrate that the Shenzhen port presents mounting challenges to the Hong Kong port,descending from a transshipment hub of China to a regional load center of Southeast China.Furthermore,this paper explores five points that have led to the evolution of the port system in the PRD:1) competition in the regional port systems;2) different interested parties;3) shift of investment strategies of in-ternational terminal operators;4) integration of shipping networks and reorganization of carriers;and 5) cost-based competition.     

内蒙古小东沟钼矿外围找矿前景分析

通过对小东沟钼矿的勘查和研究,类比外围物探异常和矿化特征,探讨了该地区钼矿和铅锌矿的成矿地质条件,提出小东沟钼矿外围综合利用物探成果进行找矿的思路及找矿前景。研究认为,该地区有望成为大型钼多金属矿床。     

大城市边缘新兴城区地域空间结构的形成与演化趋势--以天津滨海新区为例

作为大城市边缘区的新兴城市化地区，近年来凭借其用地空间广阔、限制因素少、区位条件好等优势而在许多城市尤其是沿海大城市的经济发展中迅速崛起，成为大城市空间扩展的主要方向和引起大城市地域空间结构发生根本性变化的主要力量地区。文章以天津滨海新区为研究对象，从城市地域功能、空间布局、空间联系等几个方面系统分析了大城市边缘新兴发展城区地域空间结构形成与变化的历史过程、现状格局，并对其未来发展的趋势进行了预测，指出了在发展过程中存在的一些有待解决的矛盾与问题，以定性的宏观分析研究，为我国其他大城市地区的空间发展研究提供了一个较为典型的比较案例。     

Changes in hydrodynamic process dominance (wave,tide or river) in foreland sequences: The subalpine Miocene Molasse revisited (France)

A comprehensive sedimentological study was undertaken in the Miocene of the subalpine massifs and southern Jura (France) with the aim to constrain the evolution of process changes in third-order sequences of peripheral foreland basins during the overfilled phase (i.e. sediment supply higher than accommodation space). Fieldwork analyses based on 35 sedimentological sections allowed the identification of four depositional models: wave dominated, mixed wave-tide, river to tide and river dominated. The sections were dated using chemostratigraphy (i.e. marine strontium isotopic ratios), revealing three-third-order sequences between the Upper Aquitanian and the Langhian. Chronostratigraphical and sedimentological results document prominent and recurrent changes in depositional models along third-order sequences: (i) in the earliest stage of the transgression, mixed-energy coastal environments influenced by the local coastal morphology prevailed (in palaeo-highs or incised valleys); (ii) during the course of the transgression, Gilbert delta deposits suggest a prominent steepening linked to a tectonic uplift in the proximal depozone (between the tectonically active frontal part of the orogenic wedge and the proximal foredeep). Instead, in the distal depozone (between the proximal foredeep and the proximal border of the flexural uplifted forebulge), deposits were characterized either by wave-dominated or mixed wave-tide environments and are likely eustatically-driven; (iii) during the maximum flooding stage, water depth remained shallow below the storm-weather wave base; and (iv) during the regression, the proximal depozone is characterized by the progradation of gravel-rich fan deltas. In the distal depozone, mixed wave-tide systems preceded the development of river to tidal depositional environments. These results were integrated and compared with facies models from other basin analogues worldwide. A model tackling the evolution of process changes within third-order sequences (of the overfilled phase) of foreland basins is proposed, thereby improving sequence stratigraphic predictions in foreland basins.     

塔里木盆地和田河气田周缘构造演化、成藏与勘探领域

以寻找塔里木盆地碳酸盐岩油气勘探接替领域为目的,在和田河气田周缘采用古构造演化的方法,结合和田河气田单井油气水分析,建立了玛南奥陶系潜山准层状成藏模式和玛北台缘带古油藏成藏模式;指出和田河气田周缘存在玛南奥陶系潜山、玛北奥陶系台缘带和玛东奥陶系推覆构造带三大油气勘探领域,区带资源量约1万亿m ³,是塔里木盆地碳酸盐岩勘探的重要接替领域。玛南奥陶系潜山暴露时间长,风化、淋滤作用强,形成良好的岩溶型储层,上覆石炭系泥岩和上倾位置的致密灰岩作为盖层,形成良好的储盖组合,同时处于有效生烃范围之内,是有利勘探领域。玛北发育奥陶系台缘带,而且与构造圈闭相叠置,可以捕获早期运移的油气,是较有利勘探领域。玛东奥陶系推覆带潜山披覆圈闭发育,规模较大,是潜在勘探领域。     

Hercynian-Indosinian Sedimento-Tectonic Evolution of the Nanpanjiang Basin

Following the orogeny in the Early Palaeozoic, the tectonic evolution of the Nanpanjiang basin in the Hercynian-Indosinian stage constituted a complete Wilson Cycle, made up of the stages of early rifting (D-P1), late rifting and passive margin developement (P2-T1), and peripheral foreland basin developement (T2-T3). The REE data of the initial Early Triassic basalts from the southern part of the basin has verified the existence of the oceanic crust once in the basinal evolution. The basin developed into a foreland one in the Middle-Late Triassic, indicating that the Yangtze plate once collided with the Indo-Sinian plate along the Black River fracture zone.     

河北蔡家营铅、锌、银多金属矿区外围找矿探讨①

蔡家营铅锌银矿区位于华北地台北缘,为规模大、品位高的中温热液型铅锌银多金属矿床,文章通过对矿床及其外围地质特征及物化探异常研究,认为该区成矿地质条件优越,外围应具有一定的找矿潜力,并指出矿床外围应重点工作的远景区。