顶空气中氦氖氢气相色谱测试方法及在氦资源调查中的应用

渭河盆地具有良好的氦资源前景,在勘探调查中氦气含量的测定至关重要。笔者针对渭河盆地顶空气样品中的氦氖氢测试方法与应用进行研究探讨。本方法通过气密性进样装置解决进样过程中气体样品中含较多水汽与气体逸散等问题,提高结果准确性与稳定性。采用阀切换反吹技术有效避免无关组分干扰并保护色谱柱。经多次实验优化确定仪器分析条件：载气流速14 mL/min;检测器（TCD）温度：180℃;柱箱温度：40℃;阀切换时间：0.65 min。通过检出限、正确度和精密度等参数确定了方法的可行性。最后将该方法应用于渭河盆地某剖面的顶空气样品氦气的测试中,结果满意。证明该方法具有良好的应用前景。     

深部物质运动的气体地球化学特征

根据氦同位素地球化学资料讨论了中国东部和云南腾冲地区上地幔的脱气。尽管地球脱气作用主要发生在地球形成时的十亿年间，但是后期的脱气作用仍是影响大气圈演化的主要因素。在两种力学性质不同的构造带──中国东部大陆裂谷和位于欧亚板块与印度板块缝合带的腾冲火山区，采集了天然气样，并分析了气体组分和氦同位素组成，较高的３Ｈｅ／４Ｈｅ值和地质、地球物理资料表明天然气和温泉气中的氦相当一部分是来自上地幔。来自上地幔的氦和其他气体自第三纪以来不断在气藏中聚集或向大气中逃逸。伴有源于上地幔的岩浆活动的地幔脱气是深部物质运动的具体表现形式，它对新生代气候演变可能有直接影响。     

Measurements of the helium 584 Å airglow during the Cassini flyby of Venus

The helium resonance line at 584 Å has been observed with the UltraViolet Imaging Spectrograph (UVIS) Extreme Ultraviolet channel during the flyby of Venus by Cassini at a period of high solar activity. The brightness was measured along the disk from the morning terminator up to the bright limb near local noon. The mean disk intensity was ∼320 R, reaching ∼700 R at the bright limb. These values are slightly higher than those determined from previous observations. The sensitivity of the 584 Å intensity to the helium abundance is analyzed using recent cross-sections and solar irradiance measurements at 584 Å. The intensity distribution along the UVIS footprint on the disk is best reproduced using the EUVAC solar flux model and the helium density distribution from the VTS3 empirical model. It corresponds to a helium density of 8×10⁶ cm⁻³ at the level of where the CO₂ is 2×10¹⁰ cm⁻³.     

我国氦气资源调查评价进展

<正>氦是已知的具最低熔点和沸点的元素,来源于铀、钍放射性衰变和地幔脱气,是重要的战略性稀有气体资源。因其化学惰性和沸点极低,不仅应用于制冷、医疗、半导体、科研、石化、超导实验、光电子产品生产等方面,还是军工、航天、核工业、深海潜水等领域重要的战略资源,关系国家安全和高新技术产业发展(李玉宏等,2018;张雪等,2018;陶小晚等,2019;秦胜飞等,2021)。     

从He同位素组成探讨塔里木盆地与东部诸含油气盆地天然气的成气机制

通过天然气中He同位素组成来研究天然气的成气机制。用VG-5400静态真空质谱计测定了采自塔里木盆地古生代和中生代地层中天然气的He同位素,其He/4He=2.58×10-8～8.33×10-8,R/Ra=0.019～0.059Ra,平3均值为0.031Ra,而我国东部几个主要含油气盆地天然气的R/Ra平均比值则变化于1.21～2.30Ra。He同位素组成对比研究表明,东部含油气盆地成烃作用是在幔源热流驱动下热水流体与烃源岩水岩反应形成的,而塔里木盆地成烃热源则主要是盆地地热增温热水流体与烃源岩水岩反应形成的。     

北京丰台大灰厂井氦气释放特征探讨

结合观测环境条件,温度、大气降水等影响因素及强震响应,研究了大灰厂井氦气释放成因.结果显示,氦气释放与特殊的地质环境、温度有关,与大气降水无明显关系.     

Characteristics of helium accumulation in the Guanzhong Basin,China

Guanzhong Basin is located in the transitional zone between the Qinling orogenic belt and the Ordos plateau. Analyses of drill and geothermal wells depict that the Guanzhong Basin has abundant gas, and its major source rocks are the U-rich granites. In this study, the granitoid intrusive samples were collected from the Huashan, Baoji, Muhuguan rocks in Guanzhong Basin. A micro laser Raman spectrum examination was used to measure the composition of inclusion in the granite quartz fissures. The results depict that the inclusions include both gas-liquid and H₂O-NaCl-CO₂ inclusions and that their composition primarily includes H₂O and CO₂, with small amounts of CH₄, H₂ and H₂S. These inclusions can be classified into nearly-primary, early secondary, and late secondary inclusions, which have homogenization temperatures of greater than 430 °C, 330–370 °C and 170–230 °C, respectively, based on the inclusion measurements. Additionally, the apatite fission-track investigations of six samples, which were collected from the granites at Huashan, Baoji rocks and the southern margin of Muhuguan along with the Cretaceous Sigou Formation sandstones that are located in the northwestern margin of the Guanzhong Basin reveal that the northern Guanzhong Basin began to receive deposits as early as 84–69 Ma. This period was accompanied by the rapid uplift of the Qinling orogenic belt, which was followed by an uplift of the southern basin margin and the Qinling orogenic belt from 44–28 Ma. The authors obtained an age histogram and a probability density distribution of three sample points. The results show that the age spectra of the zircons in the Cretaceous Sigou Formation sandstones can be divided into four tectonic events. Combined with the ages of apatite fission tracks and zircon, the Guanzhong Basin has experienced five tectonic stages as follows: 28–84 Ma, 170–260 Ma, 280–510 Ma, 610–1200 Ma, and 1210–2870 Ma. Using the thermal chronology constraints, inclusion composition analyses, which include the homogenization temperature measurements, and regional burial history, this paper conclude that the early secondary inclusions are primarily composed of CO₂ and N₂, whereas the late secondary inclusions are composed of CH₄. Furthermore, this paper identify two periods of reservoir accumulation, out of which the later period is assumed to be the main accumulation period. Therefore, the period of the formation of the late secondary inclusion in the Guanzhong Basin and the Miocene era is observed to overlap with the main helium reservoir accumulation period.© 2019 China Geology Editorial Office.     

Evaluating thermal history models for the Otway Basin, southeastern Australia, using (U-Th)/He and fission-track data from borehole apatites

New apatite helium and fission-track data from the Otway Basin are consistent with previously published borehole ages, confirming earlier suggestions that existing thermal models for basin evolution should be reevaluated. Analysis of the relationship between helium ages and grain size in newly analyzed samples, as well as in samples previously reported, reveals that grain size variations may contribute to the previously reported scatter in helium ages among aliquots of the same sample. In addition, systematic variations in apatite grain size with borehole depth or temperature may also have a significant effect on the interpretation of borehole helium age data. Incorporation of the observed grain size variations in Otway borehole apatites into forward models based on published thermal histories, principally based on vitrinite reflectance and fission-track data, suggests that existing models for the eastern Otway Basin are broadly consistent with the helium data. In contrast, thermal histories for western basin boreholes, now thought to be at maximum temperatures, predict helium ages that are generally older than the observed ages, implying that basin temperatures were hotter than indicated by the models. This discrepancy is consistent with a Cenozoic heating event in parts of the western Otway Basin similar to that documented for the eastern basin. The relatively wide spread of apparent apatite fission-track (AFT) ages and compositions compared to the restricted age range of helium measurements on coexisting grains, although not conclusive, supports previous suggestions that composition does not appear to affect the sensitivity of the He closure temperature in apatite.     

Isotopic geochemistry of the groundwater system in arid and semiarid areas and its significance: a case study in Shiyang River basin, Gansu province, northwest China

 Shiyang River basin, located in the eastern part of Hexi Corridor in the middle Gansu province, NW China, is a typical arid to semiarid area. Within its drainage distance of merely 300 km, the groundwater system shows a gradual hydrochemical zonation from the upper reach to the lower reach, which is composed of hydrocarbonate, sulfate to chloride zones respectively. Variation in the saturation index (SI) of calcite and dolomite shows that, under arid to semiarid conditions, the drastic evaporation causes the groundwater quality to deteriorate in the lower reach. Isotopic compositions of H, O and He in the groundwater show that the groundwater recharge sources are mainly from meteoric water. δ³He–³He/²⁰Ne coordinates could clearly distinguish the water sources and mixing among them. In the Caiqi region, there is apparent mixing of the crevice water containing excess ⁴He with the overlying groundwater, which also implies a much lower circulation rate of the groundwater. Fairly high ³He/⁴He ratios of the groundwaters collected from the adjacent area of hidden faults along Qilian Mountains show the eminent input of mantle-derived helium, indicating that these faults not only cut the crust deeply, but are currently active. Received: 11 February 2000 · Accepted: 23 May 2000     

IP-1型离子泵测氦仪及其在放射性水化找矿中的初步试验

讨论了IP—1型离子泵测氦仪的工作原理及基本技术特性。通过野外工作,证明仪器具有性能比较稳定、灵敏度较高,便于携带等特点。介绍了仪器在已知铀矿床上开展放射性水化学找矿的试验结果。测量资料表明,在有利的地质、水文地质条件下,水氦异常能较好的指明深部铀矿化范围。