南堡凹陷4号构造带蛤坨断层特征与油气成藏关系

南堡凹陷4号构造带断裂发育,既发育沟通烃源岩的深断裂,也发育沟通浅层圈闭的次级断裂。综合利用地震、测井、岩性等资料分析断层的空间展布,计算蛤坨断层的生长指数和断层泥比率（SGR）,分析断层的活动性、封堵性,评价其输导性能,并结合其与烃源岩生排烃期的匹配关系研究断裂与油气运移、聚集的关系及控制规律。在典型油气藏剖面解剖的基础上,建立了4号构造带油气运聚成藏模式。     

Creep,stable sliding,and premonitory slip

Summary The current status of laboratory investigations into creep, stable sliding and premonitory slip is reviewed and some new material is presented. It is postulated that pre-cut rocks and those with simulated gouge layers undergo a transition with increasing confining pressure from (1) stable sliding to stick-slip, to (2) sliding along the pre-cut with deformation of the country rock, to (3) homogeneous flow of the specimen without slip along the pre-cut. Stick-slip behavior is not always present. Decreasing displacement rates are found to enhance stick-slip. Mixtures of gouge are found to be significant in controlling the behavior of sliding with 10–20 percent of anhydrite mixed with quartz or clays mixed with anhydrite shifting the sliding mode from stable stick-slip or stick-slip to stable sliding, respectively. Premonitory slip may be one of the most significant short term precursors of earthquakes. Although widely recognized in the laboratory, little systematic work has been completed. Variations in pore pressure, resistivity and seismic velocities have been investigated. Clearly much work needs to be done into these topics before a clear understanding is achieved.     

Evidence of multi-stage faulting by clay mineral analysis: Example in a normal fault zone affecting arkosic sandstones (Annot sandstones)

Fault affecting silicoclastic sediments are commonly enriched in clay minerals. Clays are sensitive to fluid–rock interactions and deformation mechanisms; in this paper, they are used as proxy for fault activity and behavior. The present study focuses on clay mineral assemblages from the Point Vert normal fault zone located in the Annot sandstones, a Priabonian-Rupelian turbidite succession of the Alpine foredeep in SE France. In this area, the Annot sandstones were buried around 6–8 km below the front of Alpine nappes soon after their deposition and exhumed during the middle-late Miocene. The fault affects arkosic sandstone beds alternating with pelitic layers, and displays throw of about thirty meters. The fault core zone comprises intensely foliated sandstones bounding a corridor of gouge about 20 cm thick. The foliated sandstones display clay concentration along S–C structures characterized by dissolution of K-feldspar and their replacement by mica, associated with quartz pressure solution, intense microfracturation and quartz vein precipitation. The gouge is formed by a clayey matrix containing fragments of foliated sandstones and pelites. However, a detailed petrographical investigation suggests complex polyphase deformation processes. Optical and SEM observations show that the clay minerals fraction of all studied rocks (pelites and sandstones from the damage and core zones of the fault) is dominated by white micas and chlorite. These minerals have two different origins: detrital and newly-formed. Detrital micas are identified by their larger shape and their chemical composition with a lower Fe–Mg content than the newly-formed white micas. In the foliated sandstones, newly-formed white micas are concentrated along S–C structures or replace K-feldspar. Both types of newly formed micas display the same chemical composition confirmed microstructural observations suggesting that they formed in the same conditions. They have the following structural formulas: Na_0.05 K_0.86 (Al _1.77 Fe_0.08 Mg_0.15) (Si_3.22 Al_0.78) O₁₀ (OH)_2. They are enriched in Fe and Mg compared to the detrital micas. Newly-formed chlorites are associated with micas along the shear planes. According to microprobe analyses, they present the following structural formula: (Al_1,48 Fe_2,50 Mg_1,84) (Si_2,82 Al_1,18) O₁₀ (OH)₈. All these data suggest that these clay minerals are synkinematic and registered the fault activity. In the gouge samples, illite and chlorite are the major clay minerals; smectite is locally present in some samples.In the foliated sandstones, Kubler Index (KI) ((001) XRD peak width at half height) data and thermodynamic calculations from synkinematic chlorite chemistry suggest that the main fault deformation occurred under temperatures around 220 °C (diagenesis to anchizone boundary). KI measured on pelites and sandstones from the hanging and footwall, display similar values coherent with the maximal burial temperature of the Annot sandstones in this area. The gouge samples have a higher KI index, which could be explained by a reactivation of the fault at lower temperatures during the exhumation of the Annot sandstones formation.     

有关断层泥采样与断层位移测量的野外工作方法问题

本文讨论、研究了断层泥采样和断层位移测量的野外工作方法问题。     

Rock friction-effect of confining pressure,temperature, and pore pressure

This paper reviews many of the mechanical properties of faulted and jointed rock under pressure and temperature and in the presence of water. At low effective confining pressures (below about 1 kilobar), the friction strength is quite variable and depends on the frictional resistance between gouge particles or asperities and on the dilatancy of the fault. At higher pressures the friction strength is nearly independent of mineralogy, temperature, and rate, at least for rocks whose friction strength is less than the failure strength. Water tends to slightly weaken the fault. The type of sliding motion, whether stick-slip or stable sliding, is much more affected by environmental and mineralogical factors. In general, stick-slip is dominant at high pressures and low temperatures, in the presence of strong minerals such as quartz and feldspar, in the absence of gouge, for lower surface roughness, and perhaps in the presence of water. The microscopic deformation mechanisms are poorly understood. At low temperatures, cataclasis dominates in rocks containing mostly quartz or feldspar, and plastic deformation in rocks containing mostly calcite or platy silicates. At high temperature most minerals deform plastically, producing a greater temperature-and rate-dependence of the friction strength. Glass has been found in some sliding surfaces in sandstone.     

Seismic tomography from local crustal earthquakes beneath eastern Rif Mountains of Morocco

We applied a tomographic method to image an aseismic strike–slip fault in North Morocco and found that the occurrence of earthquakes is not only controlled by the state of tectonic stress but also by material heterogeneity in the crust. We have constructed an integrated model of seismic, electric, magnetic and heat flow properties across northeastern Morocco primarily based on a tomography inversion of local earthquake arrival times. The seismic images obtained show a pronounced low-velocity zone at 5 km depth parallels to the Nekor fault, coinciding with an anomalously high conductive and low gravity structure, which is interpreted as a fault gouge zone and/or a fluid-filled subsurface rock matrix. Below 10 km depth, a weak positive velocity zone indicates that the fault gouge is stable. The seismicity and the seismic velocity results for the Al-Hoceimas region show that the concentrations of earthquakes are confined in the high velocity area. This anomaly is interpreted to be a brittle and competent layer of the upper crust that sustains seismogenic stress. On the eastern coast line of Morocco, we infer that a high density, high velocity body exists in the shallowest layers of the upper crust, probably formed by Miocene volcanic rocks.     

安丘—莒县断裂小店—大店段断层活动证据及断层泥分布特征初步研究

郯庐断裂带最新活动的断层分布于潍坊至嘉山一带, 而安丘—莒县断裂是郯庐断裂带的重要活动断裂之一。 基于地质考察、 高密度电法探测和钻孔联合剖面, 对安丘—莒县断裂小店—大店段断层活动证据及断层泥分布特征进行研究。 地质考察发现紫红色砂砾岩逆冲到全新世耕植土上方, 两者之间发育断层泥带, 断层泥内含少量角砾岩, 为全新世活动逆断层。 高密度电法探测结果表明断层通过位置电阻率差异明显。 钻孔联合剖面揭露的地层: 全新世耕植土、 全风化砂质泥岩、 强风化砂质泥岩、 碎裂岩、 断层泥带及中风化砂质泥岩。 钻孔K1和K2揭露深灰色断层泥带, 倾向西, 倾角约为74°, 厚度约为13.9 m, 与南侧出露的断层泥带产状相协调。 工作区范围内, 发育多处褶皱、 破碎带和断层泥带, 断层表现为全新世逆断层性质。     

The role of bedding in the evolution of meso- and microstructural fabrics in fault zones

To investigate the role of bedding in the evolution of meso- and microstructural fabrics in fault zones, detailed microscopic, mineralogical, and geochemical analyses were conducted on bedding-oblique and bedding-parallel faults that cut a folded Neogene siliceous mudstone that contains opal-CT, smectite, and illite. An analysis of asymmetric structures in the fault gouges indicates that the secondary fractures associated with each fault exhibit contrasting characteristics: those of the bedding-oblique fault are R₁ shears, whereas those of the bedding-parallel fault are reactivated S foliation. The bedding-oblique fault shows the pervasive development of S foliation, lacks opal-CT, and has low SiO₂/TiO₂ ratios only in gouge, whereas the bedding-parallel fault exhibits these characteristics in both gouge and wall rocks. The development of S foliation and the lack of silica can result from local ductile deformation involving the sliding of phyllosilicates, coupled with pressure solution of opal-CT. Although such deformation can occur in gouge, the above results indicate that it may occur preferentially along bedding planes, preceding the formation of a gouge/slip surface. Thus, in sedimentary rocks that contain phyllosilicates and soluble minerals, bedding can influence the rheological evolution of meso- and microstructural fabrics in fault zones.     

旅游地乡村聚落用地格局演变的微尺度分析——河北野三坡旅游区苟各庄村的案例实证

采取参与性农村评估PRA、GIS 技术和高清遥感影像相结合的方法,研究了25 年来典型旅游村庄苟各庄村土地用地格局的变化规律.研究发现:① 苟各庄村土地利用经历缓慢起步阶段、快速扩展阶段和平稳提升阶段三个时期,实现了从核心到外围,从平面到立体的双重拓展,集约化程度不断提升;② 苟各庄村土地利用格局变化过程与传统乡村功能解构和村庄"旅游化"过程相伴而生,逐步由从单一的村民居住型用地逐步向满足旅游者需求的住宿、购物、餐饮、娱乐等复合型用地转变.③ 自然地理环境框定了乡村聚落空间拓展的基本格局走向,市场需求快速增长是村庄功能转化的根本动力,农户行为的理性调整是村庄土地利用变化的内在动因,政府调控是村庄用地维持相对稳定的重要诱因,这些因素相互作用,共同驱动村庄用地格局的变化.④ 村庄用地格局的变化是乡村发展转型进程的综合表现形式之一.研究发现乡村用地格局演变伴随着乡村城镇化的过程,呈现出周期性特征,目前苟各庄村已进入以特色旅游城镇发展为导向的转型升级阶段.对乡村旅游发展而言,原有用地模式具有不可持续性.因此,要促进乡村旅游可持续发展,必须针对旅游型乡村用地特点和要求,充分考虑现有乡村聚落旅游用地需求,加强乡村用地规划设计和建设管理,并完善相配套的制度体系,实现乡村旅游用地模式由传统内生型"人口增长+生活需求"模式驱动,向外向型的"旅游需求+人口增长"驱动模式的转变.     

Development of schistosity by dissolution–crystallization in a Californian serpentinite gouge

To understand the behaviour and deformation mechanisms of serpentinites in the seismogenic zone we study the deformation macro- and microstructures of serpentinites along the Santa Ynez Fault in the San Andreas System. At the outcrop scale, deformation is localized in a gouge zone that shows three different structures: (1) micrometric undeformed fragments (clasts) of the previously serpentinized peridotite, (2) localized shear planes (Y and R) and (3) a penetrative schistosity (S). Observations under SEM and TEM reveal that the schistosity corresponds to serpentine fibres, parallel to each other, and whose orientation varies as they wrap around clasts. TEM micro-textures indicate that these long fibres result from continuous syntectonic growth rather than from reorientation of pre-existing fibres implying a slow transfer process that occurs at short distances. We propose a dissolution–diffusion–crystallization process for the formation of the schistosity that corresponds to a low strain-rate creeping process of deformation that can be effective in aseismic fault segments.