Hydrologic simulation of clay‐settling areas in the phosphate mining district,Florida

Clay‐settling areas (CSAs) are one of the most conspicuous and development‐limiting landforms remaining after phosphate mining. Many questions are asked by the mining and regulatory communities with regard to the correct modelling (predictive) methods and assumptions that should be used to yield viable hydrologic post‐reclamation landforms within CSAs. Questions as to the correct methodology to use in modelling/predicting long‐term CSA hydrologic performance have historically been difficult to answer because the data and analysis to support popular hypotheses did not exist. The goal of this paper was to substantially improve the data, analysis and predictive methodology necessary to return CSAs to viable hydrologic units, and moreover, to develop better understanding of the hydrology of CSAs and their ability to support wetlands. The study site is located at the Fort Meade Mine in Polk County, Florida. In this paper, continuous model simulation and calibration of study site were conducted for the hydrologic model, Hydrological Simulation Program – FORTRAN, which was generally selected on the basis of its popularity in predicting the hydrologic behaviour of CSAs. The objective of this study was to simulate streamflow discharges and stage to estimate runoff response from these areas on the basis of the observed rainfall within the CSA. A set of global hydrologic parameters was selected and tested during the calibration by the parameter estimation software PEST. A comparison of the simulated and observed flow data indicates that the model calibration adequately reproduces the hydrologic response of the CSAs. The estimated parameters can be used as references for future application of the model. Copyright © 2012 John Wiley & Sons, Ltd.     

页岩气地震勘探数据采集参数选择的研究

我国页岩气重点开展区域为南方海相沉积地层,地震地质条件相对复杂,数据采集难度较大。贵州凤冈某页岩气勘查区块,属典型的喀斯特低山地貌,地形起伏大,地震施工困难,同时寒武系下统牛蹄塘组页岩层埋藏较深,反射波能量较弱,原始资料信噪比偏低。参考邻区地震勘探经验,采用二种方法论证野外施工参数:一是在勘探区选取论证点设计物理模型进行理论计算;二是以勘查区内向斜部位设计地质模型进行正演模拟求取。在此基础上通过进行不同岩性、井深、药量等激发接收参数的试验,确定了该区块的野外施工方案。该区页岩气地震勘探野外施工参数的选择方法,有效保障了其页岩气地震勘探效果。     

高层建筑荷载引发地面沉降与隆起变形三维数值模拟

针对地下水埋深较浅地区,由高层建筑荷载引起的土体变形问题,以比奥固结理论为基础,结合土体非线性流变理论,将土体本构关系推广到黏弹塑性;同时考虑土体力学参数及水力参数的动态变化关系,建立了高层建筑荷载引发地面沉降与隆起变形的三维有限元数值模型,详细研究了高层建筑荷载影响下的土体变形特征及此过程中土体力学参数及水力学参数的变化特征。结果表明：由高层建筑荷载引起的地面沉降呈现漏斗状,以建筑物中心为漏斗中心,高层建筑荷载施加初期,高层建筑周围出现隆起,到达最大值后隆起逐渐消失;高层建筑底部浅层土体孔隙度、渗透系数及泊松比均呈现缓慢减小趋势,弹性模量呈现缓慢增大趋势;而高层建筑周围浅层土体的孔隙度、渗透系数及泊松比呈现先增大后减小的变化趋势,弹性模量则呈现先减小后增大的变化趋势;高层建筑影响区域浅部土体参数的变化趋势与土体的回弹及压缩有关。     

隧道涌水量的类型划分及预测方法

根据工程应用的目的不同将隧道的涌水量划分为施工涌水量和长期涌水量,针对涌水量预测方法常常存在使用不当的问题,在全面分析隧道涌水量预测方法的适用条件的基础上,按不同的水文地质条件提出了正确选择隧道涌水量预测方法及其计算参数的建议。     

水文水井抽水试验参数自动监测系统的研制与应用

将现代计算机检测技术与水文水井抽水试验相结合，开发研制了多参数自动监测系统，可对抽水试验中孔内水位、水温和出水量进行实时同步检测，该系统在实际工程中得到了应用与验证。介绍了该系统的组成、检测原理、主要性能参数及生产试验情况。     

判定地下水二维水动力弥散参数的直线图解法

弥散参数的求得，是正确认识地下水污染运移及对其控制的前提。本文根据极值理论和非线性方程线性化手段，导出了浓度和时间变化的线性关系，得出了确定弥散参数的直线图解法。它可以弥补其它方法的不足。借用实际弥散试验资料对其进行了检验，表明所建数学模型与实际模型之间吻合良好，即所求得的参数结果可信。     

水源热泵井回灌堵塞颗粒迁移模型的建立

以地下水源热泵井回灌中的物理堵塞问题作为研究背景,建立基于质量平衡方程来模拟多孔介质中颗粒的迁移方程和颗粒的沉积造成孔隙损伤的数学模型。该模型充分考虑了颗粒流动速度修正系数、孔隙率修正系数以及颗粒在孔隙里发生捕获率3个因素;模型的建立考虑孔隙率变化的情况,在物质的迁移和堵塞的过程中,孔隙率的变化往往也是个动态的变化过程;与传统的过滤模型相比,考虑了速度折减系数和流量折减系数后新建模型更加系统、全面。该模型为解决回灌井物理堵塞的室内外试验研究提供理论依据。     

应用地层放射性元素地球化学参数评价地层含铀远景

根据放射性元素地球化学特性和岩相建造理论,作者研究了沉积建造层位中U、Th、K的分布特征,以及它们的组分参数MA、MB同地层铀富集矿化程度的关系,通过不同矿化程度的地层中MA和MB的对比,得出4种类型矿化程度的含铀层位的MA和MB值范围,为采用放射性元素的多参数定量评价地层含铀远景提供了一定经验。     

Adaminaby Group west of Batemans Bay: Deformation and metamorphism of the Narooma accretionary complex,NSW

This study provides new structural data that show that the Adaminaby Group is part of the Narooma accretionary complex and has been overprinted by HT/LP metamorphism associated with Middle Devonian Moruya Suite intrusions. The grade of metamorphism based on Kübler Indices is the same in the Wagonga and Adaminaby Groups at Batemans Bay inferring that these rocks were involved in the same accretionary event. White micas in slates of the Adaminaby Group record apparent K–Ar ages of 384.6 ± 7.9 Ma and 395.8 ± 8.1 Ma. These ages are believed to represent the age of Middle to Upper Devonian Buckenbowra Granodiorite. Kübler Index values indicate lower epizonal (greenschist facies) metamorphic conditions and are not influenced by heating in metamorphic aureoles of the plutons. All b cell lattice parameter values are characteristic of intermediate pressure facies conditions although they are lower in the metamorphic aureole of the Buckenbowra Granodiorite than in the country rock, defining two areas with dissimilar baric conditions. East of the Buckenbowra Granodiorite, b cell lattice parameter values outside the contact aureole (x = 9.033 Å; n = 8) indicate P = 4 kb, and assuming a temperature of 300°C, infer a depth of burial of approximately 15 km for these rocks with a geothermal gradient of 20°C/km. In the metamorphic aureole of the Buckenbowra Granodiorite, b cell lattice parameter values (x = 9.021 Å; n = 41) indicate P = 3.1 kb inferring exhumation of the Adaminaby Group rocks to a depth of approximately 11 km prior to intrusion. A geothermal gradient of 36°C/km operated in the aureole during intrusion. An extensional back-arc environment prevailed in the Adaminaby Group during the Middle to Upper Devonian.     

应用航放资料寻找非放射性金属矿产效果探讨

本通过对粤北地区已知的52个非放射性金属矿床（点）的地质、物化探特征的统计资料综合分析，建立了评价非放射性金属矿产成矿远景的航空能谱参数模型，结合重磁测量、重砂测量及金属量测量成果，预测了4片非放射性金属矿产成矿远景区。