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This work evaluates objective functions for multiresponse non-linear modeling using computersimulations.Tests are performed under a variety of signal-to-noise ratios and noise variance-covariancestructures.The standard error of prediction for the model parameters,computed from 50 trials,is usedfor performance comparisons.The full rank and rank-deficient problems are considered.For the fullrank problem one model was investigated,a first-order two-step consecutive reaction model,and twoobjective functions were considered,the total sum of squares and the determinant criterion.Nodistinction could be made between the two objective functions for this model.For the rank-deficient case two models were investigated,a first-order two-step consecutive reactionas in the full rank case,and a pH titration model described by the Henderson-Hasselbalch equation.Three objective functions were investigated for the rank-deficient case,the total sum of squares,aweighted total sum of squares and the determinant criterion.The total sum of squares was found toperform poorly under all conditions tested compared to the weighted total sum of squares and thedeterminant criterion.The determinant criterion was found to perform much better than the other twocriteria when the data have a combination of a low signal-to-noise ratio and high variance-covariancenoise structure.  相似文献   
123.
Carbonate cemented zones are normally adjacent to the top overpressured surface in the central Junggar Basin,NW China.Stable carbon and oxygen isotopic compositions and petrological investigations of carbonate cements in the carbonate cemented zones indicate that:(1) carbonate cements are composed dominantly of ferrocalcite,ferroan dolomite,and ankerite;(2) carbonate cements are formed under a high temperature circumstance in the subsurface,and organic fluid migration has an important effect on the formatio...  相似文献   
124.
The application of wireline formation tester(WFT)gradually extends in oil-field with the constant improvement of instrument functions.Applications of WFT in oil and gas exploration in Tarim Oilfield,such as formation pressure measurement,are described,and testing efficiency between drill stem testing(DST)and WFT are compared,especially comprised of PVT sampling,hydrocarbon composition estimation,fluid characterization analysis and formation permeability analysis.The test results between WFT and traditional DST show that their functions can be complementary.The influence factors of WFT and the suitable applying conditions for WFT and DST are also discussed.  相似文献   
125.
试论残留型盆地研究思路和油气勘探方法   总被引:6,自引:0,他引:6  
残留型地具有抬升剥蚀剧烈,原形盆地难以恢复,经历多期构造运动的改造和建造油气成藏动力学过程复杂,热演化程度较高,油气保存条件复杂等特点,但是残留型盆地油气资源丰富,勘探前景广阔,依据残留型盆地的特征和油气资源潜力,提出应全面,发展地认识盆地,静动结合地研究盆地,运用先进而实用的新技术新方法评价盆地,按照勘探程序勘探盆地,在研究工作上应以分地及其邻区作为整体研究对象,以区域地质研究一石油地质研究-综  相似文献   
126.
Aliphatic hydrocarbons and PAHs in the whole soft tissues of Bathymodiolus azoricus from three Mid-Atlantic Ridge hydrothermal vents (Menez-Gwen, Lucky Strike and Rainbow), and Mytilus galloprovincialis from three contaminated coastal sites in South Portugal were analysed, and its effects on the digestive gland microsomes mixed-function oxygenase system (MFO) were assessed.Aliphatic hydrocarbons levels were present in the same magnitude in both coastal and hydrothermal environments, while the UCM (unresolved complex mixture) for coastal mussels were higher than in vent mussels. In general, significantly higher PAHs concentrations were found in coastal mussels, compared to B. azoricus where low molecular weight PAHs (2–3 rings) represented the majority of PAHs contrarily to what was observed in M. galloprovincialis. The MFO components were present in both mussel species, and were detected in vent mussels for the first time. However this system seems to have different roles in species from these contrasting environments. In coastal mussels MFO responded to hydrocarbon contamination while response in hydrothermal organisms appeared to be related mainly to endogenous factors.  相似文献   
127.
塔里木盆地阿瓦提—满加尔低梁构造特征和形成演化   总被引:9,自引:0,他引:9  
阿瓦提-满加尔低梁是介于阿瓦提凹陷与满加尔凹陷之间一个特殊的隆起构造,其在东西向上表现为宽缓的隆起形态,而在南北方向上则为凹陷面貌。该区沉积盖层可分为下、中、上3个构造层。下构造层由震旦系-泥盆系构成,所谓阿-满低梁主要即发育于该构造层。上构造层由白垩系-第四系构成,构造形态为-北西倾斜坡。由石炭系-三叠系构成的中构造层则是上、下构造层构造形态的过渡,总体上仍呈西北倾。阿-满低满自前震旦纪末塔里木运动以来经历了4大演化发展阶段:震旦纪-泥盆纪阿-满低梁形成发育阶段、石炭纪-三叠纪阿-满低梁改造阶段、侏罗纪-早第三纪北东倾斜坡发育阶段与晚第三纪-第四纪现今构造形成阶段。  相似文献   
128.
开发地震技术在扶余油层分支水平井地质设计中的应用   总被引:1,自引:0,他引:1  
大庆外围东部油田开发的目的层主要为葡萄花油层和扶余油层,其中扶余油层因储层发育差,具有低孔、低渗、低丰度的特点,其未动用储量的有效开发一直是困扰油田开发的难题之一。要应用开发地震技术,结合钻井、测井、试油、沉积相等资料,通过细致描绘肇州油田芳483区块扶余油层的构造特征,预测扶余油层内部单砂体的分布形态、厚度和展布范围,为扶余油层分支水平井设计提供地质依据,同时也为有效开发扶余油层探索了新的思路。  相似文献   
129.
中国大山阿吾拉勒成矿带形成于石炭纪—二叠纪裂谷地质背景之上,其中段已发现著名的式可市台富铁矿床以及伴生的一系列铜矿点,成矿围岩为浅变质岩系。笔者根据近年研究,确定该含矿岩系实际是区域性挤压构造形成的动力变质岩带,其中云母片岩的绢云母经~(40)Ar/~(39)Ar定年,获得坪年龄220.6±3.4Ma和等时线年龄220.7±6.6Ma。这一成果揭示天山山脉在后碰撞地壳演化阶段,经历了晚三叠世构造热事件的改造。  相似文献   
130.
南海岩石圈破裂方式与扩张过程的三维物理模拟   总被引:5,自引:2,他引:5  
南海的形成演化一直是国内外关注的热点之一.为了揭示南海的构造演化过程, 分析对比了3组物理模拟实验.实验结果表明, 断裂样式和裂谷带的走向与岩石圈的初始热流变结构密切相关.对比模拟结果与陆缘的断层样式, 推测在张裂初期, 陆坡区比陆架区具有相对热减薄的岩石圈, 从而导致不同构造位置上发育不同的裂陷特征.受下地壳和软流圈韧性流动的影响, 断层越是靠近扩张区, 倾角变得越平缓.实验揭示, 破裂首先以点状出现, 这些点不断扩大并互相连接形成连续的扩张区.共轭边缘常具有对称的形状, 向海盆方向对凹或者对凸.当离散边界附近有刚性块体时, 扩张区域的边界会明显受到地块边缘形态的影响.通过模拟实验, 推测破裂过程可能以较粘性的方式进行.西北次海盆的发育可能是沿着中-西沙地块北缘深裂陷槽破裂的结果.   相似文献   
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