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11.
通过断裂分析及构造演化,并结合油气地化指标,综合研究认为,哈得逊油气的总体运移特征为“多期充注,晚期成藏”,即有垂向又有横向。海西末期-喜山期主干断层继承性活动,形成断穿石炭系底部的复活断层及伴生断层,沟通寒武系、奥陶系油源。晚加里东期、晚海西期来自寒武-奥陶系的油气沿羊屋2 井区深大断裂纵向运移,哈得逊石炭系整体南倾,未发育有效圈闭,两期油气均未有效成藏。晚喜山期受南北向造山运动影响,石炭系地层发生翘倾作用,形成有效圈闭。同时,古生界的深大油源断裂复活,聚集在奥陶系古油藏中的油气沿断裂垂向调整至石炭系东河砂岩,并在北倾斜坡的背景下,油气自北向南短距离侧向运移,聚集于哈得逊石炭系圈闭中,形成现今哈得逊油藏。 相似文献
12.
Based on the observations of a squall line on 11 May 2020 and stratiform precipitation on 6 June 2020 from two X-band dual-polarization phased array weather radars (DP-PAWRs) and an S-band dual-polarization Doppler weather radar (CINRAD/SA-D), the data reliability of DP-PAWR and its ability to detect the fine structures of mesoscale weather systems were assessed. After location matching, the observations of DP-PAWR and CINRAD / SA-D were compared in terms of reflectivity (ZH), radial velocity (V), differential reflectivity (ZDR), and specific differential phase (KDP). The results showed that: (1) DP-PAWR has better ability to detect mesoscale weather systems than CINRAD/SA-D; the multi-elevation-angles scanning of the RHI mode enables DP-PAWR to obtain a wider detection range in the vertical direction. (2) DP-PAWR’s ZH and V structures are acceptable, while its sensitivity is worse than that of CINRAD/SA-D. The ZH suffers from attenuation and the ZH area distribution is distorted around strong rainfall regions. (3) DP-PAWR’s ZDR is close to a normal distribution but slightly smaller than that of CINRAD/SA-D. The KDP products of DP-PAWR have much higher sensitivity, showing a better indication of precipitation. (4) DP-PAWR is capable of revealing a detailed and complete structure of the evolution of the whole storm and the characteristics of particle phase variations during the process of triggering and enhancement of a small cell in the front of a squall line, as well as the merging of the cell with the squall line, which cannot be observed by CINRAD/SA-D. With its fast volume scan feature and dual-polarization detection capability, DP-PAWR shows great potential in further understanding the development and evolution mechanisms of meso-γ-scale and microscale weather systems. 相似文献
13.
Determination of total sulfur in geothermal water by inductively coupled plasma-atomic emission spectrometry 下载免费PDF全文
Sulfur speciation and concentration in geothermal water are of great significance for the research and utilization of the water resources. In most situations, it is necessary to determine the total sulfur in geothermal water. In this study, the method was established for the determination of determining total sulfur content — the inductively coupled plasma-atomic emission spectrometry (ICP-AES), with the wavelength of 182.034 nm selected in spectral line of sulfur. It was identified that the optimal working conditions of the ICP-AES instrument were 1 200 W for high frequency generator power 9 mm for vertical observation height, 0.30 MPa atomizer pressure, and 50 r/min analytical pump speed. The matrix interference of the method was eliminated by the matrix matching method. Using this method, sulfur detection limit and minimum quantitative detection limit were 0.028 mg/L and 0.110 mg/L, respectively, whilst the linear range was 0.0–100.0 mg/L. The recovery rate of sample was between 90.67% and 108.7%, and the relative standard deviation (RSD) was between 0.36% and 2.14%. The method was used to analyze the actual samples and the results were basically consistent with the industry standard method. With high analysis efficiency, the method has low detection limit and minimum quantitative detection limit, wide linear range, good precision and accuracy, and provides an important detection method for the determination of total sulfur in geothermal water. 相似文献
14.
为了获取参数井压裂设计的相关参数,需要对井眼进行阵列声波测井和微侧向电阻率测井,需要采取大直径岩心进行力学实验。采用固体岩心钻探取心工艺,钻孔口径难以达到物探测井仪器入井要求,岩心直径也不能满足实验要求,必须采用大口径取心工艺才能满足设计要求。同时,常规取心工艺难以满足页岩气勘探对岩心(页岩或者煤心)提升时间的要求,绳索取心工艺在这方面优势明显。本篇介绍了大口径绳索取心工艺在页岩气地质调查井川蔺参1井的成功应用,根据大口径绳索取心钻具的结构特点,结合目的层岩性特征,总结了合理的取心钻进工艺参数和技术保障措施,取得了较好的效果。 相似文献
15.
David A.Wood 《地学前缘(英文版)》2021,12(6):444-457
The capability of accurately predicting mineralogical brittleness index(BI)from basic suites of well logs is desir-able as it provides a useful indicator of the fracability of tight formations.Measuring mineralogical components in rocks is expensive and time consuming.However,the basic well log curves are not well correlated with BI so correlation-based,machine-learning methods are not able to derive highly accurate BI predictions using such data.A correlation-free,optimized data-matching algorithm is configured to predict BI on a supervised basis from well log and core data available from two published wells in the Lower Barnett Shale Formation(Texas).This transparent open box(TOB)algorithm matches data records by calculating the sum of squared errors be-tween their variables and selecting the best matches as those with the minimum squared errors.It then applies optimizers to adjust weights applied to individual variable errors to minimize the root mean square error(RMSE)between calculated and predicted(BI).The prediction accuracy achieved by TOB using just five well logs(Gr,pb,Ns,Rs,Dt)to predict BI is dependent on the density of data records sampled.At a sampling density of about one sample per 0.5 ft BI is predicted with RMSE~0.056 and R2~0.790.At a sampling density of about one sample per 0.1 ft BI is predicted with RMSE~0.008 and R2~0.995.Adding a stratigraphic height index as an additional(sixth)input variable method improves BI prediction accuracy to RMSE~0.003 and R2~0.999 for the two wells with only 1 record in 10,000 yielding a BI prediction error of>±0.1.The model has the potential to be applied in an unsupervised basis to predict BI from basic well log data in surrounding wells lacking mineralogical measure-ments but with similar lithofacies and burial histories.The method could also be extended to predict elastic rock properties in and seismic attributes from wells and seismic data to improve the precision of brittleness index and fracability mapping spatially. 相似文献
16.
洪水型重力流是重力流沉积学的研究热点,以往研究认为洪水型重力流具有紊流支撑的流体性质,对于其流体性质转化及其沉积记录的识别不够深入。近年研究揭示重力流沉积过程中可形成多种过渡型流体,具有特殊流体转换机制和沉积特征。通过调研国内外最新文献,系统介绍了过渡型流体基本特征、沉积机制方面的研究进展,并讨论了其对洪水型重力流沉积研究的启示及地质意义。研究结果表明:在少量黏土矿物影响下,沉积物重力流流体的性质即可由紊流向层流转化,形成特殊的过渡型流体。转化过程主要取决于黏土矿物含量和类型控制的流体内聚力和流速控制的紊流应力二者之间的相互作用。过渡型流体可以产生大型流水沙纹(large current ripple)、砂质纹层—泥质纹层间互形成的低幅度沙波(low amplitude bed wave)等独特的底床类型。尽管实验研究揭示了过渡型流体可能形成的沉积底床特征,针对洪水型重力流沉积记录中过渡型流体的解释仍十分缺乏,尤其是过渡型流体转换机制及其沉积响应仍亟待深入探索。过渡型流体的沉积底形是研究洪水型重力流沉积动力机制的重要载体,可为深入理解洪水型重力流沉积过程提供新视角,同时可能具有更广泛的沉积学研究价值。 相似文献
17.
《地学前缘(英文版)》2023,14(1):101482
The Cathaysia block located at the southeast South China block (SCB) is considered formed by the amalgamation of the east and west Cathaysia blocks along the Gaoyao–Huilai and Zhenghe–Dapu deep faults (here referred as GHF and ZDF, respectively). Although the extension of the ZDF to the northeast, which represents the amalgamation of the two sub-blocks has been confirmed, the development of the GHF to the southwest remains to be verified. To better constrain the detailed deep structure beneath the southwest Cathaysia, which hold great significance for revealing the evolution of the SCB, a linear seismic array with 331 nodal geophones was deployed across the Sanshui basin (SSB). Combining with the regional 10 permanent stations (PA), we obtained two profiles with teleseismic P-wave receiver function stacking. The most obvious feature in our results is the ascending Moho towards the coastal area, which is consistent with the passive margin continental and extensional tectonic setting. The stacking profile from the dense nodal array (DNA) shows that the Moho is offset beneath the transition zone of the Nanling orogeny and SSB. We deduce that this offset may be casued by the deep extension of the GHF, which represents the remnants of the amalgamation of the Cathaysia block. From the other evidences, we infer that the widespread and early erupted felsic magmas in the SSB may have resulted from lithospheric materials that were squeezed out to the surface. The relative higher Bouguer gravity and heat flow support the consolidation of magmas and the residual warm state in the shallow crustal scale beneath the SSB. The sporadic basaltic magmas in the middle SSB may have a close relation to deep extension of the GHF, which serves as a channel for upwelling hot materials. 相似文献
18.
A towing experiment was conducted using a modulated wave train to investigate the vertical bending responses of a hydro-structural container ship model. In the experiment, a spatially periodic modulated wave train, as a model of a freak wave in successive high waves mimicking the so-called three sisters, was generated by the recently established higher-order spectral method wave generation (HOSM-WG) method. HOSM-WG enables us to control the location and timing of the maximum crest height in a wave tank. With precise control of the towing carriage, an experiment was conducted in which the timing of the encounters between the ship model and the modulated wave train was accurately determined. The maximum sagging moment (SM) was found to increase in proportion with the encounter wave height. However, because of differences in the relative depth of the fore and aft troughs, the maximum SM is highly variable for a given wave height. The temporal wave-geometry evolution caused the relative trough-depth to vary significantly within a wave period in the vicinity of the maximum crest height. As a result, depending on the encounter timing, the SM varied considerably for a given wave height. The temporal variation of the wave geometry is a robust feature of a modulated wave train and is common between the spatially periodic and temporally periodic modulated wave trains. 相似文献
19.
The present study investigates the combined wave field that is induced by the continuous interaction of plane waves with an array of truncated circular cylinders in front of a rigid wall. The long-term goal of the study is the investigation of possible increase in the efficiency of cylindrical Wave Energy Converters (WECs) by putting in the vicinity of the array a barrier to propagation, a wall, that could assist the reflection of the incoming waves. The main task is to develop a generic solution method that is free of conceptual simplifications employed, e.g. by the method of images and the assumption of “pure” wave reflection. To cope with the set task, the proposed method relies on the semi-analytical formulation of the velocity potentials, while the solution is sought by combined expressions that involve polar and elliptical harmonics. The wall is represented as an elliptical cylinder with zero semi-minor axis. This assumption has eventually a beneficial effect to the underlying formulation given that it simplifies significantly the expansions of the involved diffraction potentials. 相似文献
20.
Subramani Saravanan Govindan Nagarajan Radhakrishnan Ramanujam Santhanam Sampath 《洁净——土壤、空气、水》2011,39(6):515-521
The main objective of this work is to investigate the factors influencing the NOx control of a stationary diesel engine fuelled with crude rice bran oil blend with lesser effect on smoke density and brake thermal efficiency (BTE). Fuel injection timing, percentage of EGR, and fuel injection pressure are chosen as the factors for the objective and NOx emission, smoke density, and BTE are considered as the response variables. To critically analyze the effects of the chosen factors on the objective three levels were chosen in each factor and the experiments were designed by following the design of experiments method. Taguchi's L9 orthogonal array was used to conduct the tests with different combination of factor levels. Through analysis of variance (ANOVA) method, the most influencing factors and also the significance of each factor affecting each response variable were found out. Response graph was drawn for each response variable to determine the optimum combination of factor levels in achieving the objective and the obtained combination was confirmed experimentally. 相似文献