Yang Ming et al.-GGR: Blind Curtain Stone Laser Original U-TH-PB Fixed Annual Analysis of SM-ND isotope

The brown curtain stone belongs to the green curtain stone minerals. It is a common auxiliary mineral that is widely existed in the system of fire rocks, metamorphic rocks and thermal liquid. Because brown curtain stone is rich in trace elements such as LREE, SR, TH, and U, the brown curtain U-TH-PB is possible to analyze the SM-ND isotopes of the year. Therefore, brown curtain stone has significant significance and broad application prospects in terms of studying magma process, deterioration, dive material circulation, and hot -liquid mineral mining process.

Diluration of isotope-thermal power ionization method (ID-tims) is a traditional method that determines the age of brown curtain U-TH-PB age and SM-ND isotope. The complex brown curtain stone sample is analyzed, and the method also involves tedious chemical pre -processing process, which greatly limits the wide use and promotion of this method. With the development of analytical technology, the U-TH-PB annual U-TH-PB of the microcontroller and SM-ND isotope analysis technology have been widely used in recent years. The micro-zone analysis method of brown curtain stones reported by predecessors mainly focused on the second ionic mass spectrometry (SIMS) and laser erosion inductance coupling plasma mass spectrometry (LA-ICP-MS) U-TH-PB on brown curtain stones Annual analysis. However, compared to other auxiliary minerals (vermiculite, lonely, phosphorus, and vermiculite, etc.), the current standard substances of the brown curtain stone U-TH-PB are still lacking. At the same time, the analysis of the in-position SM-ND isotope of the original position of brown curtain stone has attracted more and more attention. Pre-person usually uses non-base matching external bids (artificially synthetic glass standard substances) for correction, which will have a certain impact on accurately determining the composition of brown curtain SM-ND isotope. Therefore, it is urgent to develop standard substances for brown curtain SM-ND isotope.

In response to the above -mentioned scientific issues, Yang Ming, a senior engineer and partners of the State Key Laboratory of the Institute of Geology and Geophysics of the Chinese Academy of Sciences, and his tutor Yang Yue Hengzheng senior engineer and his collaborators (University of Toronto, German Land Research Center, British Geological Survey) Nine (age range of 2650 ~ 12mA) brown curtain stone samples from the global scope are the research objects, and the brown curtain stone U-TH-PB of the LA-(MC) -iCP-MS technology is established. The ND isotope analysis method has developed a standard substance of multiple brown curtain U-TH-PB annual and SM-ND isotope analysis. The specific results are as follows:

(1) Analysis of the U-TH-PB age of brown curtain stone samples in situ (Figure 1) in situ for laser micro-zone (Figure 1). The U-PB age of vermiculite and vermiculite is consistent, and the reliability of the brown bell stone U-TH-PB of the laser micro-region is verified. Electronic probe analysis and laser trace element analysis test the average nature of the main trace element of the sample, develop multiple brown curtain stone U-TH-PB annual standard substances (including A007, A011 and A012), and use ID-tims technology to determine The reference value (Figure 2).

Figure 1 The brown curtain stone sample obtained by the LA-ICP-MS method (A) A007 (Sweden), (B) A011 (United States), (C) A012 (Germany), and (D) SQ-51 (Vietnam) T-W The average age of 206pb/238U corrected with 207PB correction

Figure 2 ID-tims measurement (A) A011 (US), (B) A012 (Germany), (C, D) A007 (Sweden) brown curtain stone sample U-PB age harmony and map. Among them, (A-C) University of Toronto Test, (D) German Land Studies Center Test

(2) For the first time, multiple brown curtain stone U-TH-PB fixed-year standard substance SM-ND isotope composition (Figure 3) is used to perform SM-ND isotope analysis of brown curtain stone. The results obtained by the solution analysis method or the results of the previous reports were consistent with the previous error range, which verified the feasibility of the analysis of the brown bell stone SM-ND isotope analysis of the laser micro-region. This study repeatedly analyzed the laser-laser original Pitoma-NM-ND isotope analysis of brown curtain stones, and the average one of the sample SM-ND isotope was tested. Among them, DAIBOSATSU (Figure 3C) and LE40010 (Figure 3D) brown curtain stone are the ideal laser micro-region SM-ND isotope analysis standard substance. At the same time, the accurate determination of the 147SM/144ND ratio is also discussed on the impact of the initial 143ND/144ND ratio and εnd (t) of the trusted initial 143ND/144ND (Figure 4). Studies have shown that during the analysis of laser micro -level, in order to obtain an accurate 147SM/144ND ratio, it is necessary to use the standard substances matched by the matrix.

Figure 3 The brown curtain stone sample obtained by the LA-MC-ICP-MS method (A) CAPB (Italy), (B) TARA (Australia), (C) DAIBOSATSU (Japan), (D) LE40010 (Danish) SM -ND isotope analysis results.

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The research results were published in the international academic journal Geostandards and Geoanalytical Research (Yang Ming, Yang Yueheng, Kamo S L, ROMER R L, Roberts N M W, Wang Hao, Xie Liewen, Huang Chao, Wu Fuyuan. 2022. Natural Allanite Reference MaterTh-PB and SM -DSOTOPIC Analysis by La- (MC) -ICP-MS [J]. Geostandards and Geoanalytical Research. Doi: 10.1111/GGR.12417).Funding from the Study Abroad Fund Committee (202004910582).Beautiful editor: Chen Feifei

School pair: Wanpeng

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