大别造山带上部地壳结构的有限差分层析成像   总被引：33，自引：7，他引：33       下载免费PDF全文

王椿镛  张先康 《地球物理学报》1997,40(4):495-502

将有限差分层析反演方法用于大别造山带人工地震测深剖面上部地壳初至波的走时层析成像，得到这一剖面上部地壳横向不均匀结构图像表明，在南大别地区的超高压变质带发现榴辉岩相岩石，其下方3km深度以内的基底仍具有大陆地壳构造中正常的结晶基底速度（6．00km／s左右）；北大别地区在整个上地壳保持正常的速度，而在超高压带下方3km深度以下为6．20-630km／s的相对高速异常区，这一现象可能与超高压变质岩的含量增大有关．同时还表明，南大别和北大别之间至少在上地壳已有明显差异，它们之间的水吼一五河断裂可能是大别造山带内部的主要构造分界线．  相似文献   

利用黄土剖面的古土壤年龄研究毛毛山断裂的滑动速率   总被引：11，自引：3，他引：11       下载免费PDF全文

袁道阳 《地震地质》1997,19(1):2-8

利用１４Ｃ、热释光（ＴＬ）样品年代及扩散方程计算结果，结合区域黄土剖面中古土壤年龄，对毛毛山地区晚第四纪各级地貌年龄进行了对比研究。根据毛毛山活动断裂水平位移和垂直位移分布明显的分组特征，求得毛毛山断裂带不同段落不同时段的平均滑动速率。大约自中更新世晚期以来，毛毛山断裂走滑段的平均水平滑动速率为２．３～３．９ｍｍ／ａ，垂直滑动速率为０．０７～０．１９ｍｍ／ａ；天祝盆地倾滑段垂直滑动速率为０．１１～０．８６ｍｍ／ａ。沿断裂带滑动速率具明显的非均匀性特点，表现为自东向西水平位移具累积滑动亏损特征，垂直位移则具补偿性  相似文献   

岩溶发育区供水井施工工艺          下载免费PDF全文

刘广才 《探矿工程》1997,(4):51-52

分析了岩溶区供水井施工困难的原因，并从钻井、成井工艺方面就防治地面塌陷和克服井孔弯曲、坍塌、延长供水井寿命等问题进行了探讨。  相似文献   

电镀PDC石油全面钻头及其在油气田中的应用          下载免费PDF全文

胡三虎 《探矿工程》1997,(1):45-46

采用低温电镀工艺生产ＰＤＣ石油全面钻头对金刚石无任何热损伤，对喷咀进行组合设计，在两口井中进行试验，取得了很好的经济效益和社会效益，并分析了钻头的特点及存在的问题。  相似文献   

秦岭巴山地区高陵─达县重磁剖面初步解释     

刘俊岭 《陕西地质》1996,(1)

高陵－达县剖面位于秦岭中段，斜跨中朝准地台、秦岭褶皱系、扬子准地台三大构造单元。在研究剖面实磁场特征的基础上，综合地质、物性、省内及邻省深部物探资料，建立了剖面地质－地球物理模型，依此对剖面通过地段的地壳结构、断裂带深部特征、三大构造单元的深部格架进行了解释推断。  相似文献   

茅台酒酿酒高梁的地质环境研究   总被引：2，自引：0，他引：2  

杨立铮  朱赫宇 《地学前缘》1996,3(2):224-233

茅台酒对酿酒高梁有严格要求，适于茅台酒传统酿造工艺的高梁只产于仁怀县的某些地区，主要是受地质环境的控制。仁怀高梁对某些常量和微量元素有着鲜明的选择性，对磷和钼表现出强烈的吸收作用。岩－土剖面元素的迁聚，对磷和铝的供应是确定仁怀高梁品质和产量的关键。侏罗系砂泥岩、二叠系煤系地层的岩－土剖面，元素淋溶微弱，总量丰富，有效态含量高，组合良好，能正常进行岩－土－高梁系统的物质转化与元素迁移，能充分供应高梁生长所需的磷和钼等元素，是茅台酒酿酒高梁的最宜种植区。  相似文献   

地震和测井资料联合反演储层物性参数的方法   总被引：2，自引：0，他引：2  

沙磊  叶霞 《物探化探计算技术》1997,19(1):12-18

为了充分利用测井资料较高的纵向分辨率及其反映井壁周围物性直接准确的特点和地震资料良好的横向可追踪性，针对厚储层和薄储层地震—地质模型分别提出了利用测井和地震资料联合反演纵横波速度和密度参数的方法。理论模型的计算结果表明，反演方法是切实可行的  相似文献   

The identifiability of parameters in a water quality model of the Biebrza River, Poland   总被引：1，自引：0，他引：1  

Marcel van der Perk  Marc F. P. Bierkens 《Journal of Hydrology》1997,200(1-4):307-322

The identifiability of model parameters of a steady state water quality model of the Biebrza River and the resulting variation in model results was examined by applying the Monte Carlo method which combines calibration, identifiability analysis, uncertainty analysis, and sensitivity analysis. The water quality model simulates the steady state concentration profiles of chloride, phosphate, ammonium, and nitrate as a function of distance along a river. The water quality model with the best combination of parameter values simulates the observed concentrations very well. However, the range of possible modelled concentrations obtained for other more or less equally eligible combinations of parameter values is rather wide. This range in model outcomes reflects possible errors in the model parameters. Discrepancies between the range in model outcomes and the validation data set are only caused by errors in model structure, or (measurement) errors in boundary conditions or input variables. In this sense the validation procedure is a test of model capability, where the effects of calibration errors are filtered out. It is concluded that, despite some slight deviations between model outcome and observations, the model is successful in simulating the spatial pattern of nutrient concentrations in the Biebrza River.  相似文献   

Observations of particle movement in a monitoring well using the colloidal borescope     

Peter M. Kearl 《Journal of Hydrology》1997,200(1-4):323-344

The colloidal borescope consists of a set of lenses and miniature video cameras capable of observing natural particles in monitoring wells. Based on field observations of these particles, it appears possible to measure in situ groundwater velocity in a well bore. Field observations have shown that directional measurements using the colloidal borescope are generally in good agreement with expected flow directions. However, the magnitude of flow velocity is higher compared with values based on conventional test methods. High relative flow velocities, even after correction factors have been applied to compensate for well bore effects, are believed to be due to preferential flow zones in the surrounding aquifer. Low flow zones exhibit swirling multidirectional flow that does not allow for a linear velocity measurement. Consequently, groundwater flow velocities measured by the colloidal borescope in heterogeneous aquifers will be biased toward the maximum velocity values present in the aquifer. A series of laboratory experiments was conducted to assess the reliability of the instrument. Based on this work, a seepage velocity correction factor ( ) of 1–4 was found for quantifying groundwater seepage velocity in the adjacent aquifer from observations in a well bore. Laboratory measurements also indicate that preferential flow in the surrounding aquifer dominates flow in the well. Results of this work suggest the possibility of quantifying higher-flow velocities associated with preferential flow zones in the subsurface.  相似文献   

Crustal structure of Dabieshan orogenic belt   总被引：2，自引：0，他引：2  

Chunyong Wang  Xiankang Zhang  Buyun Chen  Xuebo Chen  Songyan Song  Jinhan Zheng  Hongxiang Hu  Hai Lou 《中国科学D辑(英文版)》1997,40(5):456-462

The crustal structures ofP velocity and density on the deep seismic sounding profile across the Ilabieshan orogenic belt are presented. There is a 5-km-thick crustal “root” between the Yuexi and Xiaotian where the elevation is highest on the profile. An apparent Moho offset of 4. 5 km beneath the Xiaotian-Mozitan fault marks the paleo-suture of the Triassic collision. A high-velocity anomaly zone at the depth below 3 km beneath the ultra-high pressure (UHP) zone may be correlated to the higher content of UHP metamorphic rocks. Project supported by the National Natural Science Foundation of China and the Joint Earthquake Science Foundation.  相似文献