Lu-Hf同位素的MC-ICP-MS实验方法及其在华北克拉通典型火山岩研究中的应用

Over past ten years, a great development has been made in the Lu-Hf isotopic system with the advent of MC-ICP-MS. Based on a comprehensive review of available references in the related field, a novel analytical protocol of three exchange chromatographies after one mixed acid attacking geological samples was developed in this work, which not only avoids common multiple sample treatments for natural inhomegeneous samples, but also is useful for Rb-Sr, Sm-Nd and Lu-Hf isotopic system simultaneously, especially for the garnet- and apatite-bearing rocks for the Sm-Nd and Lu-Hf geochronology. An analytical procedure for the Lu and Hf concentration in geological samples determined by by ID-MC-ICP-MS was detailedly investigated. The Hf yield is > 90 % and total procedural blank is less than. 50 pg for Hf and 10 pg for Lu, respectively. The developed method was successfully applied to the determination of Lu and Hf concentrations for USGS geological materials. A one-column procedure for Hf purification in geological samples using common anion exchange chromatography and its isotopic analyses by MC-ICP-MS were also established. Multiple analyses of Standard Reference Materials demonstrate that this method was simple, time-saving, cheap and efficient, especially suitable for the Hf isotopic compositions of young samples. Finally, the measurements of Sr and Nd isotopic compositions using Neptune MC-ICP-MS were described briefly, which indicates that Neptune MC-ICP-MS can precisely measure Sr and Nd isotopic compositions as the TIMS does, even more efficient and less time-consuming than the TIMS method. The Hf isotopic characteristics of typical volcanic rocks (Cenozoic Changle-Linqu basalts, Mesozoic Fangcheng basalts, Mesozoic Jianguo basalts, Mesozoic Wulahada high-Mg andesite, Cenozoic Fanshi, Zuoquan and Xiyang-Pingding basalts of the Taihang Mountains, Paleozoic diamondiferous Menyin and Fuxian Kimblites) from the North China Craton were firstly studied in this work. Coupled with Nd isotopic compositions, it shows that the Hf isotopes could be a better tracer for mantle sources than the Nd isotopes. Individual kimberlite fields from both the Mengyin and Fuxian regions have quite uniform Hf isotopic compositions, similar to the situation for the Nd isotopes.

高含水油藏复合驱剩油分布研究-以羊三木油田馆陶组油藏复合驱为例

Based on the study of the combined flooding test block of Guantao formation in Third faulted block of Yangsanmu oil field, this paper carries out the integration of reservoir precise characterization for very high water cut reservoir, establishes precise 3D geologic model for high water cut development period and states the changing law of the reservoir architecture dtiring development by combined flooding. Then, by subdivided the thick oil reservoir, the study of remaining oil saturation monitoring in fiber glass cased well and tracer monitoring is developed. According the study of multiple constrained combined flooding reservoir numerical simulation, remaining oil distribution are predicted, the methods architecture of predicting remaining oil distribution are established for fluvial facies reservoir at late development stage, develops plan is designed and adjustment associating technologies for enhancing oil recovery. On these base, related measures for tapping the potential are given, it is verified and optimized through the field former test and the good economic effect is achieved . The major achievements of this paper are as follows. The changing law of the reservoir architecture and it's property parameters is revealed, The result indicates that the temperature-pressure of the injecting material and the interaction effect of the injecting material and reservoir petrography are the main factors of the dynamic changes of the reservoir architecture. The quantitative reservoir geologic model, which is tallied with dynamic reservoir parameters of the study area, is established. Subdivided the thick oil reservoir is very important for the study of the remaining oil distribution within the thick oil reservoir. Subdivided the thick oil reservoir technology, which consists of six technologies as follow: micro-cyclic divided, flow unit method, architectural element method, high resolution log technology, high resolution-process technology for normal logging data and using the production data is presented. 3. It is established dynamic monitoring system of remaining oil saturation quantitative research which are inner and interlayer remaining oil saturation from time-lapse logging in fiber glass cased well, inter-well remaining oil saturation from the technology of isotopic tracer monitoring technology, and 4d remaining oil saturation distribution from combined flooding numerical modeling integrated by production datao The forming mechanism of remaining oil for polymer flooding and alkali/polymer combined flooding is clarified, and the plane and vertical distribution law of remaining oil after combined flooding is revealed. Predicting methods and technologies for the combined flooding reservoir of fluvial facies is developed. Combined flooding has been achieved good displacement result in the pilot of Third fault block in Yangsanmu oil field, and accumulated types of important parameters and optimum plans, this technology of combined flooding is expected to increase recovery ratio by 4.77%.