鹤煤集团寺湾煤矿断层导水通道综合分析及治理

鹤煤集团寺湾矿由于受F8断层影响,断层东翼奥灰水侧向补给西翼二灰含水层,使该矿水文地质条件复杂化,存在突水隐患。采用瞬变电磁勘探、地质钻探、放水试验等手段进行综合分析,查明F8断层导水通道的具体位置。通过地面帷幕注浆,封堵断层带附近二灰岩裂隙,沿断层西盘形成一道连续的阻水帷幕,切断奥灰水对二灰水的补给通道,降低矿井的排水量。通过注浆,奥灰水通过F8断层侧向补给西翼二灰的水量由原来的802m3/h减少到202m3/h,断层堵水率为74.8%,堵水效果明显。该研究对今后矿井水害治理,具有一定的参考意义。     

布尔矩阵乘快速算法探讨

本文探讨将图的可迁闭包算法,大型稀疏矩阵的优化压缩存储技术应用于布尔矩阵乘。并且根据两相乘布尔矩阵A,B的不同情况,提出不同的处理方法,得出了几个实用的处理布尔矩阵乘的较优算法,     

Regional-Scale Excess Ar wave in a Barrovian type metamorphic belt, eastern Tibetan Plateau

Laser step heating ⁴⁰Ar/³⁹Ar analysis of biotite and muscovite single crystals from a Barrovian type metamorphic belt in the eastern Tibetan plateau yielded consistent cooling ages of ca. 40 Ma in the sillimanite zone with peak metamorphic temperatures higher than 600°C and discordant ages from 46 to 197 Ma in the zones with lower peak temperatures. Chemical Th‐U‐Total Pb Isochron Method (CHIME) monazite (65 Ma) and sensitive high mass‐resolution ion microprobe (SHRIMP) apatite (67 Ma) dating give the age of peak metamorphism in the sillimanite zone. Moderate amounts of excess Ar shown by biotite grains with ages of 46 to 94 Ma at metamorphic grades up to the high‐grade part of the kyanite zone probably represent incomplete degassing during metamorphism. In contrast, the high‐grade part of the kyanite zone yields biotite ages of 130 to 197 Ma. The spatial distribution of these older ages in the kyanite zone along the sillimanite zone boundary suggests they reflect trapped excess argon that migrated from higher‐grade regions. The most likely source is muscovite that decomposed to form sillimanite. The zone with extreme amounts of excess argon preserves trapped remnants of an ‘excess argon wave’. We suggest this corresponds to the area where biotite cooled below its closure temperature in the presence of an elevated Ar wave. Extreme excess Ar is not recognized in muscovite suggesting that the entrapment of the argon wave by biotite took place when the rocks had cooled down to temperatures lower than the closure temperature of muscovite. The breakdown of phengite during ultrahigh‐pressure (UHP) metamorphism may be a key factor in accounting for the very old apparent ages seen in many UHP metamorphic regions. This is the first documentation of a regional Ar‐wave spatially associated with regional metamorphism. This study also implies that resetting of the Ar isotopic systems in micas can require temperatures up to 600°C; much higher than generally thought.     

准噶尔盆地滴南凸起早石炭世火山岩的成因及其对克拉美丽洋闭合时限的约束

准噶尔盆地陆梁隆起南缘的滴南凸起地区广泛发育石炭系凝灰岩,本文对滴南凸起滴西14井的石炭系流纹质凝灰岩的锆石SHRIMP年龄、地球化学与构造环境进行了系统研究.样品中锆石具有明显的振荡环带特征,SHRIMP锆石U-Pb 年龄(337.2Ma)揭示该凝灰岩形成于早石炭世.火山岩样品具有较高的硅含量(SiO2=63.47％～ 77.36％),低钛(TiO2=0.19％ ～ 1.01％)、钠(Na2O=0.98％ ～4.01％)、Mg#(21 ～ 53)的特点,K2O/Na2O比值为0.56～2.09,A/CNK大于1;稀土元素总量偏高,具有明显的负铕异常,La/Nb比值介于1.71 ～3.74之间,原始地幔标准化的蛛网图显示:大离子亲石元素Rb、Th、Ba等相对富集,高场强元素Nb、Ta,尤其是Sr、P、Ti负异常明显,以上地球化学特征表明滴南凸起石炭系凝灰岩具有壳源特征,为活动大陆边缘产物.且滴西14井岩性综合柱状图显示,深部和浅部凝灰岩具有相似的地球化学特征,浅部凝灰岩SiO2含量相对低于深部.结合火山岩锆石SHRIMP年龄和区域地质背景分析得出:盆地内陆东地区在早石炭世仍处于洋壳消减环境,洋盆闭合时间不早于337.2Ma.克拉美丽-三个泉(陆梁隆起)-达尔布特代表的洋盆从早石炭世末期开始,自东向西呈“剪刀式”闭合模式.石炭纪在准噶尔地区存在多岛格局,从滴南凸起早石炭世火山岩的成因以及盆地周围地区的构造背景来看,岛弧最终的相互拼贴可能构成了准噶尔盆地基底的主体.另外,该区来自壳源的凝灰岩中并未见到老的继承性锆石,表明准噶尔盆地可能不存在前寒武系基底.     

Energy- and flux-budget (EFB) turbulence closure model for stably stratified flows. Part I: steady-state,homogeneous regimes

We propose a new turbulence closure model based on the budget equations for the key second moments: turbulent kinetic and potential energies: TKE and TPE (comprising the turbulent total energy: TTE = TKE + TPE) and vertical turbulent fluxes of momentum and buoyancy (proportional to potential temperature). Besides the concept of TTE, we take into account the non-gradient correction to the traditional buoyancy flux formulation. The proposed model permits the existence of turbulence at any gradient Richardson number, Ri. Instead of the critical value of Richardson number separating—as is usually assumed—the turbulent and the laminar regimes, the suggested model reveals a transitional interval, , which separates two regimes of essentially different nature but both turbulent: strong turbulence at ; and weak turbulence, capable of transporting momentum but much less efficient in transporting heat, at . Predictions from this model are consistent with available data from atmospheric and laboratory experiments, direct numerical simulation and large-eddy simulation.     

湍流输送的非线性热力学性质

湍流输送是一种热力学不可逆过程,本文利用非线性热力学研究了湍流输送的特征. 将热力学流对热力学力以平衡态作为参考态进行Taylor展开,可以得到湍流输送系数是系统宏观参量梯度的Taylor级数. 线性湍流输送系数是Reynolds湍流闭合方案的K闭合湍流输送系数;而湍流输送系数非线性项则是系统偏离热力学平衡态所造成的热力学非线性效应. 湍流输送系数这一热力学性质提供了一种热力学湍流闭合方案. 线性湍流输送系数是正定的,湍流输送只能使系统宏观参量均匀化;而在远离平衡态的热力学非线性区,可能导致湍流输送系数负黏性现象. 在最小熵产生态的条件下,热力学流对热力学力Taylor展开的各级系数间存在一种递推关系. 利用这种递推关系大大减少了由实验确定的Taylor级数的系数个数.     

新疆哈尔里克山地区晚石炭世火山作用:锆石U-Pb年代学、元素地球化学及Sr-Nd同位素研究

新疆哈尔里克地区出露大面积的石炭纪火山岩,岩石类型包括玄武岩、安山岩和流纹岩等。然而目前对该套火山岩的形成时间仍缺乏较精确的年代学约束,其成因和构造属性(岛弧/陆内环境)也存在较大分歧。本文选择哈尔里克地区的火山岩剖面进行研究,通过LA-ICP-MS锆石U-Pb定年获得该套火山岩形成于约302Ma,为晚石炭世火山喷发的产物。地球化学数据表明,基性火山岩为拉斑质玄武岩系列,低Ti/Y(343~406)和Ce/Y(1.5~1.7),具有正ε_(Nd)(t)值(+3.9)和低初始~(87)Sr/~(86)Sr_((i))值(0.7043),表明玄武岩起源于同位素适度亏损的岩石圈上地幔。相对而言,中酸性火山岩则表现出高场强元素(HFSE;Nb、Ta、Ti等)负异常和大离子亲石元素(LILE;LREE、Sr、Ba等)富集的特征,与典型的弧岩浆岩类似,ε_(Nd)(t)和~(87)Sr/~(86)Sr_((i))值分别为+3.3~+6.0和0.7032~0.7046,具有较年轻的Nd模式年龄(t_(DM)=543~797Ma),指示中酸性岩浆源自年轻岛弧基底的重熔。哈尔里克晚石炭世火山岩的形成标志着大洋向大陆环境的转变,是后碰撞伸展转换背景下软流圈物质上涌诱发岩石圈上地幔和年轻下地壳再次熔融的结果。     

利用信息矩阵算法搜索GPS网的最短独立闭合环

针对独立闭合环自动生成经典算法中多解性和环长未定两个问题,应用闭合环网形的信息矩阵,顾及边长因素,提出了一种基于矩阵运算的新算法,生成的闭合环满足最短独立闭合环的所有要求。     

A comparison of wind-tunnel experiments and numerical simulations of neutral and stratified flow over a hill

A comparison is made of numerical and experimental results for flow over two-dimensional hills in both neutral and stably stratified flow. The numerical simulations are carried out using a range of one-and-a-half order and second-order closure schemes. The performance of the various turbulence schemes in predicting both the mean and turbulent quantities over the hill is assessed by comparing the results with new wind-tunnel measurements. The wind-tunnel experiments include both neutral and stably stratified flow over two different hills with different slopes, one of which is steep enough to induce flow separation. The dataset includes measurements of the mean and turbulent parts of the flow using laser Doppler anemometry. Pressure measurements are also made across the surface of the hill. These features make the dataset an excellent test of the model performance. In general second-order turbulence schemes provide the best agreement with the experimental data, however, they can be numerically unstable for steep hills. Some modifications can be made to the standard one-and-a-half order closure scheme, which results in improved performance at a fraction of the computation cost of the second-order schemes.