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应用岩石热解数据S2-TOC相关图进行烃源岩评价 总被引：1，自引：0，他引：1
应用岩石热解数据评价烃源岩的传统方法具有一定的局限性。由于矿物基质的吸附或“死碳”的影响,有机质类型的“范氏图解”往往夸大烃源岩有机质类型的非均质性。对松辽盆地上白垩统不同有机质丰度和有机质类型的烃源岩生烃动力学研究表明,它们具有相似的生烃动力学特征,说明尽管有机质丰度存在较强的非均质性,但其有效源岩类型（区别于应用范氏图划分的有机质类型）是一致的。这些烃源岩的岩石裂解烃（S2）与有机质丰度（TOC）的相关系数很高,与生烃动力学的分析结果一致,表明应用S2-TOC相关图划分烃源岩的有机质类型可以更真实地反映烃源岩的有效源岩类型,S2-TOC相关图是评价烃源岩有效源岩类型的有效手段。过去岩石热解数据用于反映烃源岩成熟度的主要指标是tmax,tmax对于偏Ⅱ／Ⅲ型的烃源岩比较适用,而对于Ⅰ型烃源岩,由于生油窗内变化不明显,tmax不能完全反映有机质的成熟过程;而且tmax也受运移油等其他因素影响。不同成熟度的烃源岩的S2-TOC图分析结果显示,随着成熟度的增加,S2-TOC的回归斜率和TOC逐渐减小;利用不同成熟度的烃源岩建立的S2-TOC图可用于评价烃源岩的成熟度。松辽盆地不同沉积相中烃源岩的S2-TOC相关图的特征表明。只要有有利的有机质保存条件,各沉积相下均可发育优质的烃源岩;S2-TOC相关图可以反映烃源岩形成的沉积环境和有机质保存条件。 相似文献
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The alignments of the strapdown inertial navigation system (SDINS) utilizing GPS carrier phase rate measurements is introduced. In this paper, a measurement model of GPS carrier phase rate under two antenna configurations is derived in order to be used for the SDINS alignment process. For in-flight alignment, the performance of the proposed SDINS/GPS integration method is analyzed using the covariance analysis and the overall performance is briefly confirmed by the navigation result of a van test. Furthermore, we find that during in-flight alignment the proposed SDINS/GPS integrated system using GPS carrier phase rate measurements can be implemented in real time because the integer ambiguity problem resulting from carrier phase measurements is avoided. 相似文献
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The typical shape of a capillary-pressure curve is either convex (e.g., Brooks–Corey model) or S-shaped (e.g., van Genuchten model). It is not universally agreed which model reflects natural rocks better. The difference between the two models lies in the representation of the capillary entry pressure. This difference does not lead to significantly different simulation results for modeling CO2 sequestration in aquifers without considering CO2 dissolution. However, we observe that the van-Genuchten-type capillary-pressure model accelerates CO2 solubility trapping significantly compared with the Brooks–Corey-type model. We also show that the simulation results are very sensitive to the slope of the van-Genuchten-type curve around the entry-pressure region. For the representative examples we study, the differences can be so large as to have complete dissolution of the CO2 plume versus persistence of over 50% of the plume over a 5000-year period.The cause of such sensitivity to the capillary-pressure model is studied. Particularly, we focus on how the entry pressure is represented in each model. We examine the mass-transfer processes under gravity-capillary equilibrium, molecular diffusion, convective mixing, and in the presence of small-scale heterogeneities. Laboratory measurement of capillary-pressure curves and some important implementation issues of capillary-pressure models in numerical simulators are also discussed. Most CO2 sequestration simulations in the literature employ one of the two capillary-pressure models. It is important to recognize that these two representations lead to very different predictions of long-term CO2 sequestration. 相似文献
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AbstractIn this paper, two analytical models used worldwide to assess salinity variation in alluvial estuaries are applied to the Ashtamudi estuary, a Ramsar site, southwest coast of India; and Bouregreg estuary, in northwest part of Morocco. The estuaries’ bathymetry is described by an exponential function. Both models are quite similar and use a predictive equation for the dispersion in the estuary mouth (D0). The major difference between the two models is the use of the constant value of K?=?0.5 for the Van der Burgh coefficient (K) and the introduction of the correction factor ζ, which is a function of damping (δ) and shape (γ). The performance of these two models was evaluated by comparing their results with field measurements; this revealed that both analytical models apply well to both the estimation of salinity distribution and the prediction of salt intrusion in the Ashtamudi and Bouregreg estuaries (Ashtamudi: RMSE = 0.60–1.22 ppt; Bouregreg: RMSE = 0.92–2.71 ppt). One model agrees more with the field measurements of salinity distribution along the estuaries axis; the second underestimate and overestimate some values of salinity distribution along the estuaries. Possibly, the constant value of K?=?0.5 for the Van der Burgh coefficient (K) has applicability limits for the estuaries under tidal conditions. The specifying of the parameterization may be a field of research. 相似文献
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利用黄河利津站的精密水文泥沙测量结果对一些常用水流泥沙输沙率公式进行验证表明，Ｖａｎ Ｒｉｊｎ公式最适合于黄河泥沙输沙率的预测，对公式做部分校正则可以大大提高其预测能力。 相似文献
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Determining the optimum weight of the armor blocks is of vital importance in the design of conventional breakwaters. The widely used formulae in the literature include the transition region from plunging to surging waves. In this paper, it is aimed to investigate a new design formula without any transition region as an alternative to widely used Van der Meer formulae. The dimensionless parameters of Van der Meer formulae as well as newly generated variables are used as inputs. Nonlinear surface fit best subset regression model is used to find the optimum input combination that keeps the nonlinear relationships. All the input parameters, their second powers, and their two-way interactions are included in the regression analyses to obtain a nonlinear surface fit. Various goodness of fit statistics are applied to check the different perspectives of the model accuracy. It is demonstrated that the proposed model gives a realistic prediction of the stability number for critical data range. Especially for high values of stability number the proposed formula outperforms the benchmark formulae of Van der Meer and Etemad-Shahidi and Bonakdar. The other advantage is that it does not contain any transition region that depends on wave conditions. Besides, there is no need to include “number of waves” and “permeability” parameters into the equation. 相似文献
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准确的磁场模型对于辐射带粒子环境研究至关重要.本文利用美国Van Allen Probes（VAP）在2012至2018年期间测量的磁场数据和GOES15在2011至2017年期间测量的磁场数据,定量地评估了三个较新的外磁场经验模型（TS05、TA15和TA16）对外辐射带区域（3~6.6RE）磁场的描述性能.本文选择预测效率（Prediction Efficiency,PE）作为评估指标,定量分析各模型在不同空间范围（Lm值）、不同地磁活动水平（Kp）以及不同磁地方时（MLT）下的性能表现,并且计算了观测磁场与模型磁场的夹角θ,以评估模型的磁场方向预测能力.结果表明：PE随Lm值增大,随地磁扰动增强而下降;θ随Lm值增大,随地磁扰动增强而增大.在Lm=5~6.5RE范围内,PE呈现晨昏不对称性,MLT=12-21时的PE值小于MLT=0-9时的值,说明三个磁场模型可以较好地描述晨侧磁场的强度,但它们并不能很好地反映下午至昏侧磁场的大小;在地球同步轨道附近（Lm~6.6RE）,PE呈现昼夜不对称性,MLT=9-15时的PE值大于其他时区的值,说明三个磁场模型可以很好地反映昼侧磁场大小,但在夜侧可能存在较大的误差.θ在MLT=6-12时的值小于其他时区的值,呈现昼夜不对称性,说明三个磁场模型可以较好地描述昼侧磁力线的分布位型,但在夜侧存在较大的方向描述误差.在外辐射带3~6.5RE内,TA16模型与VAP磁场观测数据最为接近,PE均大于0.7,θ均小于3°;在地球同步轨道高度（6.6RE）,TS05模型与GOES15卫星磁场观测数据最为接近,PE约为0.75,θ约为7°.相关的研究结果可以为我国星载高能粒子探测器探测数据的在轨交叉定标、辐射带高能粒子动态模型研究和相关的磁层环境理论/应用研究提供地磁场模型选择方面的参考. 相似文献
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Murat Utkucu 《Journal of Seismology》2006,10(1):105-117
The water level in Lake Van has shown alternating rises and decreases in history, causing economical, environmental and social problems over the littoral area. The water level changes were obtained to be in the order of 100 m between 18000 and 1000 B.C., in the order of 10 m between 1000 B.C. and 500 A.D. and relatively stable and fluctuating in the order of a few metres during the past 1500 years. The most recent change of the water level took place between 1987 and 1996, during which the water level increased episodically about 2 m and its altitude changed from approximately 1648.3 m to about 1650.2 m. All these changes were mainly related to climate changes. In this study, the water level changes in the lake after 1860 are compared with the seismic activity of faults lying close to the basin. Temporal correlations of seismicity with the water level changes are very persuasive and dramatic, indicating hydrogeological triggering of the earthquakes. This study shows that 14 M ≥ 5.0 earthquakes and increasing number of 4.0 ≤ M < 5.0 earthquakes accompanied or followed the dramatic (about 1 m or larger) changes of the annual mean of the water level in the lake and that there was a tendency of M ≥ 4 earthquakes to occur between November and February, during which the lake level is low within a year. 相似文献