A Pre-Treatment Method for the Determination of Organic Carbon Isotope Composition in Sedimentary Rocks
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摘要:
沉积岩的有机碳同位素研究是地质学领域的重要内容，可为地质历史时期的古环境重建、古气候变化解析、碳循环过程理解以及能源资源勘探开发提供重要信息。由于沉积岩中的有机碳主要以干酪根的形式赋存，因此，在获取沉积岩有机碳同位素值之前，需要先对岩石样品开展干酪根提取预处理。提取过程需使用大量危险化学品，制备流程长且面临化学品使用受限等诸多挑战。因此，在实际工作中，亟需开发一种更为便捷、环保的前处理方法。本文建立了一种简易的酸处理方法，实验选取110件不同岩性(灰岩、页岩、油页岩）和不同有机碳含量范围(0.83%～35.33%)的沉积岩样品进行该前处理方法与传统干酪根提取前处理方法的比对实验。结果表明，对于94%的样品，本次建立的前处理方法和干酪根提取方法获得的碳同位素值差值均小于1.0‰，满足行业标准方法重复测定的偏差要求。表明该前处理方法可以有效地实现沉积岩样品中有机碳的分离，进而准确获取有机碳同位素值这一关键地质参数。而且，样品的有机碳含量及岩性未对测定结果产生明显影响，显示该方法对常规地质样品的适用性，可满足地质勘探调查工作需求。
要点(1)沉积岩有机碳同位素测试需以干酪根提取制备为前提，制备流程长，且面临化学品使用受限等诸多挑战，需要开发更为便捷、环保的前处理方法。
(2)建立了一种基于稀盐酸实现沉积岩中有机碳组分有效分离的前处理方法，具有流程简洁、实验耗材易获取、样品用量少等优点。
(3)对比了传统的干酪根提取方法与本文建立的前处理方法对不同TOC值、不同岩性样品有机碳同位素值测定的影响，证明了本文方法对于页岩、灰岩等常见地质样品的适用性。
HIGHLIGHTS(1) The organic carbon isotope test of sedimentary rocks should be based on the extraction and preparation of kerogen, which has a long preparation process and requires the use of a significant quantity of hazardous chemicals. Therefore, more convenient and environmentally friendly pretreatment methods need to be developed.
(2) A pre-treatment method for effective separation of organic carbon components from sedimentary rocks based on dilute hydrochloric acid was established, which has the advantages of simple process, easy access to experimental consumables, and less sample consumption.
(3) The influence of the traditional kerogen extraction method and the pre-treatment method established on the determination of organic carbon isotope values of samples with different TOC values and different lithologies is compared, which proves the applicability of this method for common geological samples such as shale and limestone.
Abstract:The organic carbon in sedimentary rocks is mainly in the form of kerogen, and it is necessary to extract kerogen from samples before obtaining the organic carbon isotope value. The extraction process requires a significant quantity of hazardous chemicals and a long preparation process. Therefore, in daily work, there is an urgent need to develop a more convenient and environmentally friendly pre-treatment method. A simple acid treatment method was established, and 110 sedimentary rock samples with different lithology (limestone, shale, oil shale) and different organic carbon content range (0.83%−35.33%) were selected for comparison experiments of two pretreatment methods. The results show that for 94% of the samples, the difference of carbon isotope values obtained by the acid pretreatment method established in this study and the kerogen extraction method was less than 1.0‰, which met the deviation requirements for repeated measurements, indicating that this pretreatment method can be used to accurately obtain the key geological parameter of an organic carbon isotope value. Furthermore, the organic carbon content and lithology of the samples does not influence the results, demonstrating the applicability of this method to typical geological samples and fulfilling the requirements of geological exploration and investigation. The BRIEF REPORT is available for this paper at http://www.ykcs.ac.cn/en/article/doi/10.15898/j.ykcs.202403110038.
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Keywords:
- carbon isotope /
- sedimentary rock /
- pretreatment method /
- acid treatment /
- kerogen
BRIEF REPORTSignificance: The carbon pool in sedimentary rocks comprises both organic and inorganic carbon. Organic carbon predominantly exists in the form of kerogen, which accounts for over 80% of the total organic carbon in these rocks, while inorganic carbon primarily occurs as carbonate[1-2]. There are notable differences in the isotopic values of organic and inorganic carbon, each bearing distinct geological significance[3-6]. Currently, it is widely accepted that the stable carbon isotope value of organic matter is largely determined by its source[7-9], remaining relatively unaffected by thermal evolution. This characteristic renders it a valuable tool for distinguishing types of organic matter in the field of oil and gas geochemistry[10-15].
Since organic carbon in sedimentary rocks primarily exists in the form of kerogen, it is necessary to extract kerogen from samples before obtaining the organic carbon isotope value[30-32].
The preparation process of kerogen is complex and time-consuming, which limits the rapid acquisition of organic carbon isotope data from sedimentary rocks and affects the geological research and exploration evaluations. Furthermore, a significant amount of chemical reagents are utilized in the kerogen preparation process, which can have considerable environmental impacts. Consequently, some researchers have proposed a pretreatment method that only uses hydrochloric acid to replace the pretreatment process of kerogen preparation[33-36]. This method is simple and efficient, and it has garnered significant attention from scholars in recent years. However, the current application objects of this method are mainly modern sediments, while the data for ancient sedimentary rocks are very limited. There is also a lack of systematic comparison of the impact of the two pre-processing methods on the organic carbon isotope value determination of rock samples with different lithology and TOC values. It is not clear whether this simple pretreatment method can completely replace the kerogen extraction method[33-41].
This study established a pre-treatment method for effective separation of organic carbon components from sedimentary rocks based on dilute hydrochloric acid, and experiments were conducted using samples of various lithologies and organic carbon contents, including shale, limestone, and oil shale. The results demonstrate that the organic carbon isotope data obtained through this pre-treatment method are comparable to those acquired via the traditional kerogen extraction method. This research offers a more convenient and environmentally friendly pre-treatment method for isotope research in sedimentary rocks samples.
Methods: 110 typical profile rock samples were collected from Qiangtang Basin, including shale, oil shale and limestone. Each crushed sample was divided into 3 parts for pretreatment and subsequent experimental analysis. The Part 1 sample was used for extraction and preparation of kerogen, with the sample weight of about 100g. Part 2 and Part 3 samples were used to carry out acid treatment with about 5g per sample, and the organic carbon contents and isotope values were measured respectively after treatment.
The total organic carbon (TOC) content of sedimentary rock samples was determined by a Leco CS-744 carbon sulfur analyzer. The EA-IRMS combined system was used to determine the carbon isotope value of the sample. The combustion tube temperature of the element analyzer was set at 950℃, and the reduction tube temperature was set at 600℃. During the test process, the test results of standard substances and repeated samples need to meet the quality requirements of standard methods, and the carbon isotope test error of repeated samples is less than 0.5‰.
Data and Results: The research results indicate that the Δ13C value (δ13Cacid−δ13Cker) of the samples processed by the two methods ranges from −2.8‰ to 1.8‰. A correlation analysis was conducted on the isotope values obtained using these two pre-processing methods, revealing a strong consistency between the two datasets. The correlation followed the linear relationship described by the equation y=0.97x−0.61, with a correlation coefficient of R2=0.97 (Fig.1). Notably, the proportion of samples with Δ13C values less than 1.0‰ constitutes 94% of the total samples. These samples satisfy the repeatability error requirements for carbon isotope determination based on current standards, indicating that the carbon isotope values obtained through different pretreatment methods are highly comparable[2,21,24,30].
The study conducted a comparative analysis of carbon isotope data obtained through two pre-processing methods applied to samples with varying lithology (Fig.2). It was observed that shale samples were significantly more influenced by the different pre-processing methods, and a total of six shale samples exhibit Δ13C values exceeding 1.0%, significantly higher than those of other lithologies. Analysis indicates that this phenomenon may be attributed to either a relatively high clay mineral content in the shale or the presence of non-kerogen organic carbon in these samples[13,32]. However, there is currently little data in this part, and additional experiments are still needed to accurately reveal the reasons for this difference.
In addition, the article compared the conditions of samples with varying total organic carbon (TOC) contents (Fig.3). The results indicate that the TOC content does not consistently influence the differences between the two methods. Specifically, only six samples exhibit differences greater than 1.0‰, with their TOC values primarily ranging from 5.00% to 15.00%. Notably, these samples tend to have a high oil content. During the acid treatment process, an oil film forms around the samples, which hinders the acid from fully contacting and reacting with them, ultimately leading to discrepancies in the measurement results.
The study selected three crucibles with varying water permeability rates to conduct comparative experiments. The results indicate that the differences in water permeability rates of acid treatment containers do not significantly impact the organic carbon isotope values.
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水(H2O)是自然岩浆体系中最主要的挥发组分，显著影响岩浆的黏度、熔点和结晶行为，从而控制岩浆分异演化的趋势［1-3］。而熔体包裹体是在岩浆活动过程中捕获在结晶矿物晶格缺陷中的岩浆熔体［4-5］，一定程度上保留了所捕获岩浆的组分状态，可以提供岩浆作用过程的直接信息［6-8］。前人通过大量研究证实了应用熔体包裹体确定岩浆挥发份的可靠性［2，8-10］。借助熔体包裹体研究岩浆中的挥发份含量，不仅可以揭示岩浆的分异演化过程，还能为理解岩浆活动特征提供重要依据。
目前应用于测定硅酸盐熔体包裹体中的H2O的原位分析技术主要有［11-12］：电子探针(EPMA)、离子探针(SIMS)、傅里叶变换红外光谱和显微激光拉曼光谱。相较于其他方法，显微激光拉曼光谱分析具有高空间分辨率、快速、无损分析、样品制备简单等优点［13-15］，可应用于分析暴露在表面或包裹于内部的样品，并且能够在0%～20%(含水量)浓度范围内精确测定［16-19］。Thomas［16］利用显微激光拉曼光谱技术研究了26个已知成分的人工合成玻璃和天然硅酸盐熔体包裹体样品，在水含量0%～16%范围内获得与实测值基本一致的结果；Chabiron等［17］通过显微激光拉曼光谱法测试熔体包裹体水含量，该方法得到的结果与红外光谱测试结果基本一致；王玉琪等［12］使用显微激光拉曼光谱快速标定了花岗质玻璃样品，其测试结果与红外光谱水含量结果的相对误差小于10%；Tu等［19］建立了一种基于激光共聚焦拉曼光谱测定硅酸盐熔体中总溶解水及不同形态水含量的方法。上述研究进一步证实了显微激光拉曼光谱技术在测定熔体包裹体水含量方面的独特优势和可靠性。
髫髻山组火山岩是燕山造山带中生代最具代表性的钙碱性火山岩之一，代表了燕山期大规模火山喷发的开始［20］。前人的研究主要集中在燕山造山带中生代火山岩的地球化学特征［21-25］，而水作为影响岩浆形成及演化的重要因素，目前对髫髻山组火山岩中的水含量尚不清楚。柳江盆地向斜核部出露了中侏罗统髫髻山组(J2t)下部的凝灰岩［24，26］，作为火山活动早期产物，研究其岩浆中的水含量对于了解火山活动有重要意义。因此，对该凝灰岩开展岩石地球化学分析和岩浆水含量定量研究，可以为深入认识和理解该地区的岩浆活动提供重要依据。本文以柳江盆地侏罗系髫髻山组下部凝灰岩为研究对象，以岩石学、岩石地球化学和包裹体岩相学分析为基础，应用显微激光拉曼光谱法定量测定了凝灰岩中熔体包裹体的水含量，并讨论了岩浆中的水对火山喷发行为的影响。
1. 研究区地质概况
柳江盆地位于河北省秦皇岛市，其大地构造位置位于华北陆块北缘中朝地块燕山褶皱造山带东段(图1a)。盆地是一个近南北向不对称的短轴向斜(图1b)，西翼地层紧凑且直立倒转，东翼地层舒展而平缓，主要构造线偏于盆地西部，其走向大致为南北向。
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柳江盆地髫髻山组地层岩性特征［26］表现为：下部主要发育灰绿色、浅黄色的安山质、流纹质火山集块岩夹凝灰岩和火山熔岩；中部发育灰绿色安山质、角闪安山质、粗安山质火山熔岩与集块岩、角砾岩互层；上部发育黑绿色、紫红色、青灰色玄武质、玄武安山质、辉石安山质火山熔岩与熔结集块岩、集块岩互层，夹有少量的火山角砾岩及凝灰岩。由下向上，岩性由偏酸性逐渐过渡为中性、中基性。
2. 实验部分
2.1 样品及处理
本文所采集的凝灰岩样品取自河北省秦皇岛市柳江盆地髫髻山组下部野外露头。将采集的新鲜凝灰岩样品分别制备成厚约0.03mm的普通岩石薄片和厚约0.1mm双面抛光的流体包裹体薄片多张，用于显微观察和显微激光拉曼光谱测试。挑选新鲜的凝灰岩样品2块，用于全岩主量和微量元素分析。
2.2 样品测试
2.2.1 显微观察
样品的显微观察在中国石油大学(华东)深层油气全国重点实验室完成。镜下观察使用仪器为徕卡DM2700P显微镜，在透光条件下观察和记录样品的岩石学特征和熔体包裹体岩相学特征，并在镜下挑选、标记保存完好的熔体包裹体，以备显微激光拉曼光谱测试。
2.2.2 主量和微量元素分析
样品全岩主量和微量元素分析测试在中国石油大学(华东)深层油气全国重点实验室完成。全岩主量元素采用IRIS Intrepid Ⅱ XSP电感耦合等离子体发射光谱仪(ICP-OES)进行测试；微量元素和稀土元素使用ELAN9000电感耦合等离子体质谱仪(ICP-MS)进行测试。用于本次测试的凝灰岩样品为TJS-1和TJS-2，对每块样品分别进行两次测试，以保证数据可靠性，测试偏差小于1%。
2.2.3 显微激光拉曼光谱分析
人工合成硅酸盐玻璃标准样品和髫髻山组熔体包裹体样品的显微激光拉曼光谱测试在中国石油大学(华东)深层油气全国重点实验室完成。用于测试的人工合成玻璃标样依次命名为标样1～标样4，熔体包裹体则按照MI-1至MI-9顺序依次编号。为降低实际样品薄片中的黏合剂对实验的干扰，测试前使用丙酮溶液浸泡清洗薄片，风干后进行实验测试分析。实验仪器为LABRAM HR EVO型激光拉曼光谱仪(法国HORIBA FRANCE SAS公司)，使用的激光光源波长为532nm，光栅1800gr/mm，光谱分辨率≤0.65cm−1，测试精度小于±0.1cm−1，实验环境温度为20℃，湿度为50%。
2.3 测试数据质量控制
显微激光拉曼光谱法定量熔体包裹体水含量的准确性会受到拉曼光谱仪参数、拉曼图谱数据处理方法、标准样品、标定参数等方面的影响。因此，本文在使用该方法进行熔体包裹体水含量定量分析时，对上述四个方面的影响因素进行了优化，从而提高实验测试结果的准确度和精度。
2.3.1 拉曼光谱参数设置
由于过高的激光功率和积分时间可能会导致玻璃中水的丢失［11-12，19］，通过比较不同条件下的水峰强度，最终采用的实验条件为激光功率30mW，积分时间30s，积分次数3次。在使用激光拉曼光谱仪对包裹体进行测试之前，用单晶硅标准样对该仪器进行校正以确保实验结果的准确性。
2.3.2 拉曼图谱数据处理
由于拉曼光谱在测试过程中会受到硅酸盐成分、仪器及测试环境等方面的影响，需要对测试得到的拉曼光谱进行数据处理。本文结合强度校正和基线校正对实验获得的拉曼光谱进行校正，以消除上述影响。具体校正程序见2.4.2节。
2.3.3 标准样品应用
为尽可能地提高测试结果准确性，在建立熔体包裹体中水的特征峰强度与浓度之间的线性关系时，首先需要借助标准物质建立实验室标定曲线。本文通过对中国科学技术大学壳幔物质与环境重点实验室人工合成的11个不同水含量的含水玻璃标准样品测试结果进行校正(包括11个参考样品［19］和4个实测样品)，建立了实验室水含量标定曲线。
2.3.4 参数标定
拉曼光谱仪定量限定硅酸盐玻璃水含量的校正方法包括外标法和内标法［11，16］。相较于外标法，内标法在标定含水硅酸盐玻璃中水含量时更为准确且可靠，可以通过选取合适的标定参数和公式消除硅酸盐玻璃成分差异产生的影响［11］。样品的岩石学和地球化学特征表明，髫髻山组凝灰岩为酸性火山岩，而酸性硅酸盐玻璃具有较强的LF470拉曼峰高度/强度比(图2)，优先选择AWF/ALF作为最佳标定参数［11，19］。
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图 2 不同水含量人工合成流纹质玻璃的拉曼光谱红色实线为5.27% H2O人工合成标准样品的拉曼谱图；橙色实线为4.09% H2O人工合成标准样品的拉曼谱图；绿色实线为2.26% H2O人工合成标准样品的拉曼谱图；蓝色实线为1.48% H2O人工合成标准样品的拉曼谱图。LF-250cm−1～700cm−1为低波段谱带；HF-850cm−1～1300cm−1为高波段谱带；WF-3000cm−1～3800cm−1为总水谱带。Figure 2. Raman spectra of artificially synthesized rhyolitic glasses with different water content2.4 熔体包裹体水含量定量分析
2.4.1 含水玻璃标样拉曼光谱特征谱带
人工合成含水玻璃标准样品由中国科学技术大学壳幔物质与环境重点实验室提供，标样1～标样4分别为5.27% H2O、4.09% H2O、2.26% H2O 和1.48% H2O的实际测试样品，分别对应Tu等［19］的样品RH-8、RH-7、RH-5和RH-4。对人工合成含水玻璃标准样品进行显微激光拉曼光谱测试，拉曼光谱图显示，含水玻璃拉曼光谱具有三个特征谱带(图2)，与前人实验结果一致［16-17，19］。在硅酸盐玻璃的低波段谱带中，最明显的谱带在470cm−1处，这是由于桥氧(T—O—T；T=Si，Al)的弯曲振动引起的［16-17］。而高波段谱带则与非桥氧(T—O；T=Si，Al)的拉伸振动有关［28-32］。在总水谱带中，在3540～3620cm−1的宽带则是因为O—H和H2Om伸缩振动的共同作用［33-34］。
2.4.2 拉曼图谱数据处理方法
使用Origin 2018软件对拉曼光谱图进行以下光谱处理。
第一步：强度校正。对原始拉曼光谱进行Long［35］校正以获得真实的光谱强度，校正方程表示为：
$$ I=I_{{\mathrm{o b s}}}\left\{\dfrac{v_{0}^{3}\left[1-\exp \left(-\dfrac{h c v}{K T}\right)\right] v}{\left(v_{\mathrm{0}}-v\right)^{4}}\right\} $$ (1) 式中：Iobs为测量强度；v0为入射激光的波数(v0=18797cm−1)；h为普朗克常数(6.62607×10−34J·s)；c为光速(2.9979×1010cm/s)；K为玻尔兹曼常数(1.38065×10−23J/K)；T为绝对温度。
第二步，基线校正。根据样品的光谱特征分段式固定部分基线，而后使用三次样条插值法扣除基线。
第三步，谱带积分。含水玻璃拉曼光谱具有三个特征谱带，即LF、HF、WF(图2)，对基于前两步得到的拉曼光谱进行峰面积积分，分别得到LF、HF、WF的积分面积，简写为ALF、AHF、AWF。
2.4.3 熔体包裹体水含量标定曲线
前人研究证明，硅酸盐玻璃的水含量与其拉曼参数之间存在良好的线性关系［16-17，19］，但由于不同激光拉曼光谱仪的效率因子不同，其线性关系的系数会存在差异。因此，不同仪器的AWF/ALF值之间也存在良好的线性关系。通过4个人工合成标准样品确定本文实际测量值AWF/ALF与Tu等［19］测得的AWF/ALF*之间的线性关系，可以得到11个标准样品的AWF/ALF值(表1)，然后使用Origin 2018软件对标准样品进行AWF/ALF-CH2O线性拟合，得到的熔体包裹体水含量（CH2O）标定曲线如图3所示，其方程表示如下：
表 1 不同水含量人工合成含水硅酸盐玻璃标准样品的积分面积等参数测量结果Table 1. Measurement results of integrated area and other parameters of artificially synthesized water-containing silicate glasses standard samples with different water content人工合成含水玻璃
标准样品编号ALF AWF AWF/ALF*
(Tu等［19］测量值)AWF/ALF
(转换值或实测值)CH2O
(%)RH-1(Tu等，2023) / / 1.0700 0.3726 0.33 RH-2(Tu等，2023) / / 1.3300 0.4631 0.41 RH-3(Tu等，2023) / / 1.8400 0.6407 0.58 RH-4(Tu等，2023) / / 3.2600 1.1351 1.48 RH-5(Tu等，2023) / / 4.9400 1.7201 2.26 RH-6(Tu等，2023) / / 6.3100 2.1971 3.01 RH-7(Tu等，2023) / / 8.5100 2.9632 4.09 RH-8(Tu等，2023) / / 11.7800 4.1018 5.27 RH-9(Tu等，2023) / / 14.3000 4.9793 6.35 RH-10(Tu等，2023) / / 15.4400 5.3762 6.84 RH-11(Tu等，2023) / / 21.3100 7.4201 9.05 标准样品1 292.6424 1264.846 / 4.3222 5.27 标准样品2 244.9186 776.2908 / 3.1696 4.09 标准样品3 229.9241 374.9651 / 1.6308 2.26 标准样品4 189.5898 250.3734 / 1.3206 1.48 注：RH-1至RH-11为Tu等［19］测试样品；标样1至标样4为本文中的实际测试样品，分别对应Tu等［19］的样品RH-8、RH-7、RH-5、RH-4。“/”代表本文未使用的数据。 ![]()
图 3 含水流纹质玻璃水含量标定曲线Figure 3. Calibration curve for total water content in hydrous rhyolitic glasses$$ C_{\mathrm{H}_2\mathrm{O}_t}=1.26\times\left(\frac{A_{\mathrm{WF}}}{A_{\mathrm{LF}}}\right)\quad R^2=0.998 $$ (2) 3. 结果与讨论
3.1 岩石学与地球化学特征
3.1.1 岩石学特征
样品新鲜面呈灰白色，具凝灰结构、块状构造。岩石主要由晶屑(35%)、岩屑(25%)和基质(40%)组成。晶屑成分以石英、长石为主，粒径可达1.8mm；岩屑以流纹岩岩屑为主，粒径约0.5～2mm；基质由尘屑和火山灰构成。镜下观察表明，岩石发育凝灰结构、假流纹构造，发生轻微蚀变。岩石定名为流纹质岩屑-晶屑凝灰岩。
3.1.2 岩石主量和微量元素地球化学特征
柳江盆地髫髻山组凝灰岩样品全岩主量元素分析结果见表2。样品中SiO2含量为75.18%～77.14%，Fe2O3含量1.06%～2.28%，Al2O3含量12.61%～13.02%，CaO含量0.14%～1.10%，MgO含量0.65%～1.29%，TiO2含量0.14%，全碱(Na2O+K2O)含量4.04%～4.24%，Na2O/K2O值为0.56～0.65。里特曼指数(σ)为0.51～0.53，属钙碱性系列。TAS图解投图落点在流纹岩区域中(图4a)，符合样品中流纹质岩屑发育的岩石学特征，表明研究区髫髻山组下部凝灰岩的形成与酸性岩浆活动之间存在密切联系。
表 2 髫髻山组凝灰岩全岩主量元素测试结果Table 2. Analytical results of major elements in tuff of the Tiaojishan Formation凝灰岩样品
编号Na2O
(%)MgO
(%)Al2O3
(%)SiO2
(%)P2O5
(%)K2O
(%)CaO
(%)TiO2
(%)MnO
(%)Fe2O3
(%)烧失量
(%)Na2O+K2O
(%)主量元素含量
合计(%)TJS-1 1.45 1.29 13.02 75.18 0.03 2.60 1.10 0.14 0.04 2.28 3.38 4.04 100.48 TJS-2 1.67 0.65 12.61 77.14 0.02 2.58 0.14 0.14 0.03 1.06 3.04 4.24 99.07 注：为确保测试结果的可靠性，实验数据取同一样品两次测试结果的平均值。 ![]()
柳江盆地髫髻山组凝灰岩样品全岩微量元素分析结果见表3。原始地幔标准化蛛网图(图4b)显示，大离子亲石元素(Rb、Th、U、K)富集，高场强元素(Ta、Nb、Ti、Zr、P)亏损，具明显Pb正异常，Sr负异常，弱Ba、La、Ce负异常；稀土元素球粒陨石标准化曲线(图4c)呈海鸥式展布，具明显Eu负异常，说明岩浆演化过程中存在明显的斜长石分离结晶作用；稀土元素配分模式为右倾型，呈现轻稀土富集、重稀土亏损的特点。(La/Sm)N平均值为6.77，(Gd/Yb)N平均值为1.88，表明轻稀土分馏程度高而重稀土分馏程度较低；(La/Yb)N平均值为15.65，轻重稀土分馏明显。李伍平等［21］对燕山造山带中-晚侏罗世髫髻山期火山岩进行研究发现，冀北髫髻山期流纹岩样品具有轻稀土元素强烈富集、重稀土元素强烈亏损、负Eu异常、Sr含量低(94～135μg/g)等特征，与本研究中凝灰岩样品的岩石地球化学特征相似。Ta/Yb-Th/Yb图解(图4d)投点落在活动大陆边缘，指示该时期研究区受洋壳俯冲的影响，岩浆活动强烈。(La/Nb)N平均值为1.06[原始地幔(La/Nb)N值约为0.96，平均大陆壳(La/Nb)N值为2.5［39］]，指示成岩过程中受到一定地壳混染作用。上述地球化学特征与前人的研究结果［20，40-41］一致，即实验样品可以在一定程度上反映研究区髫髻山期早期的岩浆活动特征。
表 3 髫髻山组凝灰岩全岩微量元素测试结果Table 3. Analytical results of trace elements in tuff of the Tiaojishan Formation凝灰岩样品
编号Li
(μg/g)Be
(μg/g)B
(μg/g)Sc
(μg/g)V
(μg/g)Cr
(μg/g)Co
(μg/g)Ni
(μg/g)Cu
(μg/g)Zn
(μg/g)Ga
(μg/g)Ge
(μg/g)As
(μg/g)Rb
(μg/g)Sr
(μg/g)TJS-1 29.75 4.72 17.15 3.84 6.09 7.14 1.26 3.90 2.57 36.30 19.25 1.68 0.41 76.35 139.50 TJS-2 10.46 3.78 15.55 4.89 6.59 4.43 0.72 1.69 2.39 18.56 17.55 0.80 0.47 74.13 97.87 凝灰岩样品
编号Y
(μg/g)Zr
(μg/g)Nb
(μg/g)Mo
(μg/g)Cd
(μg/g)Cs
(μg/g)Ba
(μg/g)La
(μg/g)Ce
(μg/g)Pr
(μg/g)Nd
(μg/g)Sm
(μg/g)Eu
(μg/g)Gd
(μg/g)Tb
(μg/g)TJS-1 16.75 112.50 26.30 2.24 0.09 1.39 451.50 32.45 63.90 7.16 23.90 4.84 0.31 4.04 0.61 TJS-2 13.50 100.77 27.64 1.80 0.04 0.99 386.05 24.29 52.86 5.53 17.92 3.56 0.24 2.80 0.45 凝灰岩样品
编号Dy
(μg/g)Ho
(μg/g)Er
(μg/g)Tm
(μg/g)Yb
(μg/g)Lu
(μg/g)Hf
(μg/g)Ta
(μg/g)W
(μg/g)Tl
(μg/g)Pb
(μg/g)Bi
(μg/g)Th
(μg/g)U
(μg/g)TJS-1 2.95 0.63 1.65 0.27 1.91 0.31 3.97 2.02 0.51 0.63 24.40 0.16 22.40 6.35 TJS-2 2.45 0.50 1.44 0.25 1.70 0.27 3.68 2.04 0.70 0.60 20.70 0.10 21.60 5.50 注：为确保测试结果的可靠性，实验数据取同一样品两次测试结果的平均值。 3.2 凝灰岩熔体包裹体与水含量特征
3.2.1 熔体包裹体岩相学特征
对采集样品的包裹体薄片进行镜下显微观察，熔体包裹体较发育，呈孤立状随机分布在石英斑晶的晶格缺陷中，未见到边界层、破裂或泄露等明显的成分改造现象，表现出原生成因的岩相学特征［7，42］。熔体包裹体颜色复杂，呈无色或淡黄色，其形态具有多样性，发育多边形(图5中a，b)、橄榄球形(图5中c，d)及椭圆形(图5e)，直径为30～165μm。根据熔体包裹体相态特征，可将其划分为三类：①玻璃质+结晶质熔体包裹体(图5a)；②玻璃质+气泡熔体包裹体(图5中b，d)；③玻璃质熔体包裹体(图5中c，e)。熔体包裹体内部不含或只含少量真空气泡，属于冷却速率较快的喷发火山岩相［6，43-44］。其中，呈孤立状分布在石英晶屑中、无破裂和泄露现象、不含或仅含单个气泡的熔体包裹体是岩浆迅速淬火冷凝而成，所捕获的熔体没有发生物理或化学成分改造，能代表矿物结晶时周围的熔体特征。
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图 5 熔体包裹体镜下照片及熔体包裹体显微激光拉曼光谱图a为玻璃质+结晶质熔体包裹体；b、d、g、h为玻璃质+气泡熔体包裹体；c、e、f为玻璃质熔体包裹体；i为熔体包裹体MI-1减基线后的拉曼光谱图。Figure 5. Microscopic photos showing characteristics of the melt inclusions and Raman spectrum of the melt inclusions3.2.2 熔体包裹体拉曼光谱特征
髫髻山组凝灰岩中9个熔体包裹体样品的显微激光拉曼光谱测试结果显示：各熔体包裹体在3100～3800cm−1处均检测到水峰，未检测到CO2等其他挥发组分(图5f)。根据鲍文反应序列［45］，石英形成于岩浆分离结晶作用晚期，其捕获的熔体包裹体组成接近于喷发前的熔浆成分，熔体包裹体中挥发份含量可以代表喷发前岩浆中挥发份含量［2］。
3.2.3 凝灰岩熔体包裹体水含量特征
按照2.3.2节所述步骤对9个熔体包裹体样品的显微激光拉曼图谱进行处理，并将处理结果(即AWF、ALF)代入建立的水含量标定曲线方程，即2.4.3中的方程(2)，使用Excel进行计算，得到的熔体包裹体水含量结果列于表4。测定结果显示，柳江盆地髫髻山组凝灰岩石英晶屑中熔体包裹体水含量为0.99%～4.98%，平均含量为2.62%(表4)。
表 4 髫髻山组凝灰岩中熔体包裹体LF、WF积分面积及水含量计算结果Table 4. Integrated areas of LF and WF, and water content of the melt inclusions in tuff of the Tiaojishan Formation包裹体样品编号 熔体包裹体类型 ALF AWF AWF/ALF 峰位(cm−1) CH2Ot (%) MI-1 玻璃质 120.2732 203.0257 1.6880 3631 2.13 MI-2 玻璃质 119.9589 208.9559 1.7419 3631 2.19 MI-3 玻璃质 297.2329 233.0028 0.7839 3643 0.99 MI-4 玻璃质 198.5294 276.1755 1.3911 3636 1.75 MI-5 玻璃质 180.3690 306.9109 1.7016 3631 2.14 MI-6 玻璃质+气泡 78.6287 288.6345 3.6709 3636 4.63 MI-7 玻璃质+气泡 222.9093 237.9510 1.0675 3637 1.35 MI-8 玻璃质+气泡 526.2989 1446.2396 2.7479 3541 3.46 MI-9 玻璃质+结晶质 186.4130 737.1156 3.9542 3568 4.98 根据李福春等［1］的熔体包裹体水含量统计数据，大多数超基性基性岩浆中的水含量在0～0.8%；大部分中性岩浆水含量为0.4%～2.8%，平均为2.26%；酸性岩浆水含量范围主要集中在0.8%～5.6%，平均为2.712%。对比测定结果与统计数据可以看出，柳江盆地髫髻山组下部凝灰岩中熔体包裹体呈现高水含量的特点，反映了岩浆演化后期为酸性岩浆，这与岩石地球化学特征反映的岩浆性质一致，进一步验证了该时期研究区存在由地壳浅部酸性岩浆活动引发的火山爆发。
柳江盆地位于燕山褶皱造山带东段(图1a)，在中侏罗世(160±5Ma前后)受到燕山造山运动的影响强烈，研究区处于大陆边缘活动阶段(图4d)，上地幔发生部分熔融［25，40-41］，形成的岛弧拉斑玄武质岩浆随着基性矿物的分离结晶，逐渐向富硅、富水的酸性岩浆演化。水含量的增加促进了斜长石等矿物的分离结晶，导致负Eu异常(图4c)的形成［46］；高含水量的岩浆也可以促进流体相的形成，使得大离子亲石元素更容易在岩浆中富集，而高场强元素则因难以进入流体相而在残余熔体中表现为亏损［47］(图4b)，从而使其形成的火山岩具有特定的地球化学特征。此外，水作为岩浆中最主要的挥发份，控制着岩浆的脱气过程，从而显著影响了岩浆系统的喷发动力［43，48］。根据样品的熔体包裹体水含量测定结果，可以推测，高水含量岩浆是研究区髫髻山期早期爆发性火山喷发的重要驱动因素之一。
4. 结论
柳江盆地髫髻山组下部发育流纹质岩屑-晶屑凝灰岩，在地球化学上表现出富水酸性岩浆的特征：大离子亲石元素(LILEs)富集，高场强元素(HFSEs)亏损，稀土元素(REEs)配分模式呈现轻稀土(LREEs)富集、重稀土(HREEs)亏损的特点，并出现负Eu异常和明显Pb正异常、Sr负异常，代表了研究区髫髻山期早期的岩浆特征。基于人工合成标样，本文建立了显微激光拉曼光谱定量熔体包裹体水含量标定曲线，并对柳江盆地髫髻山组下部凝灰岩石英斑晶内的熔体包裹体开展了水含量定量分析。测定结果表明，该凝灰岩中熔体包裹体水含量为0.99%～4.98%，平均为2.62%，介于酸性岩浆水含量范围，指示了研究区髫髻山期早期为富水酸性岩浆。凝灰岩地球化学特征和熔体包裹体水含量测定结果均反映了柳江盆地髫髻山早期岩浆具有富水、富硅的特点。结合样品的熔体包裹体水含量测定结果和大规模火山喷发背景，推测高水含量岩浆可能是导致此次爆发性火山喷发的重要条件之一。
今后的研究中，可利用显微激光拉曼光谱法对研究区髫髻山期不同阶段的火山岩开展水含量系统分析，这对于探讨燕山造山带髫髻山期火山岩成因和岩浆演化具有重要意义。
致谢：感谢中国科学技术大学壳幔物质与环境重点实验室(合肥)高晓英教授团队提供的帮助。
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图 1 样品δ13Cacid与δ13Cker线性关系
Figure 1. The linear relationship between δ13Cacid and δ13Cker of samples
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图 2 不同岩性样品在不同|Δ13C|范围的数量统计
Figure 2. The quantitative statistics of samples with different lithology in different |Δ13C| value ranges.
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图 3 不同有机碳含量样品在不同|Δ13C|范围的数量统计
Figure 3. The quantitative statistics of samples with different TOC content in different |Δ13C| value ranges.
表 1 实验使用的标准物质及有机碳含量
Table 1 Details of reference materials and their organic carbon content
测试项目 标准物质编号 研制单位 有机碳含量推荐值(%)或
同位素组成δ13C推荐值(‰)总有机碳含量 GBW01117 江苏省铸造热处理研究所 3.08±0.02 501-676 美国力可公司 0.13±0.04 501-024 美国力可公司 3.19±0.03 502-694 美国力可公司 10.80±0.26 碳同位素组成 GBW（E）04407 石油勘探开发科学研究院 −22.43±0.3 GBW（E）04408 石油勘探开发科学研究院 −36.93±0.3 USGS24 美国地质调查局 −16.05±0.3 NBS-22 国际原子能机构 −30.03±0.05 
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表 2 样品岩性信息及TOC、δ13Cker、δ13Cacid、Δ13C测定结果
Table 2 Lithological information of samples and measured results of TOC, δ13Cker, δ13Cacid and Δ13C
样品岩性 样品数量
(件)TOC(%) δ13Cker(‰) δ13Cacid(‰) Δ13C(‰) 测定值范围 平均值 测定值范围 平均值 测定值范围 平均值 测定值范围 平均值 灰岩 39 0.83～18.69 9.62 −27.5～−22.2 −24.6 −27.3～−22.4 −24.4 −0.3～1.1 0.2 页岩 59 0.87～35.33 11.73 −34.6～−21.8 −26.3 −34.5～−20.0 −26.2 −2.8～1.8 0.1 油页岩 12 6.53～21.94 14.25 −25.8～−21.5 −24.0 −25.9～−21.1 −23.8 −0.6～0.5 0.2
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表 3 三种坩埚酸处理取得的δ13C测定结果
Table 3 The measurement results of δ13C obtained by acid treatment with three crucibles.
样品编号 δ13C测定值(‰) δ13C测定平均值
(‰)δ13C测定值
标准偏差(‰)Ⅰ型坩埚 Ⅱ型坩埚 Ⅲ型坩埚 页岩1 −33.8 −34.1 −34.1 −34.0 0.2 页岩2 −32.8 −32.8 −32.9 −32.8 0.1 页岩3 −31.3 −31.4 −31.3 −31.3 0.1 页岩4 −30.7 −30.7 −30.8 −30.7 0.1 页岩5 −30.3 −30.5 −30.5 −30.4 0.1 页岩6 −29.5 −29.4 −29.5 −29.5 0.1 页岩7 −29.4 −29.3 −29.2 −29.3 0.1 页岩8 −28.4 −28.3 −28.4 −28.4 0.1 灰岩1 −27.2 −27.3 −27.3 −27.3 0.1 灰岩2 −26.5 −26.6 −26.6 −26.6 0.1
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[1] 杜勇. 华南早三叠世异常碳-氮-硫生物地球化学循环及其控制机理[D]. 北京: 中国地质大学(北京), 2023. Du Y. Anomalous carbon-nitrogen-sulfur biogeochemical cycle in the early Triassic of South China and its controlling mechanism[D]. Beijing: China University of Geosciences (Beijing), 2023.
[2] 吴夏, 黄俊华, 白晓, 等. 沉积岩总有机质碳同位素分析的前处理影响[J]. 地球学报, 2008, 29(6): 677−683. doi: 10.3321/j.issn:1006-3021.2008.06.003 Wu X, Huang J H, Bai X, et al. Pretreatment effect of carbon isotope analysis of total organic matter in sedimentary rocks[J]. Acta Geoscientica Sinica, 2008, 29(6): 677−683. doi: 10.3321/j.issn:1006-3021.2008.06.003
[3] 王万洁, 侯兴旺, 刘稷燕, 等. 传统稳定同位素技术在环境科学领域的应用及研究进展[J]. 环境化学, 2021, 40(12): 3640−3650. doi: 10.7524/j.issn.0254-6108.2021041601 Wang W J, Hou X W, Liu J Y, et al. Application and research progress of traditional stable isotope technology in environmental science[J]. Environmental Chemistry, 2021, 40(12): 3640−3650. doi: 10.7524/j.issn.0254-6108.2021041601
[4] 王新欣. 中国南方泥炭沉积13ka以来长链正构烷烃单体碳、氢同位素组成特征及其古境意义[D]. 北京: 中国地质大学(北京), 2017. Wang X X. Carbon and hydrogen isotopic composition characteristics of long-chain n-alkanes monomer and its paleoenvironmental significance since 13ka peat deposition in Southern China [D]. Beijing: China University of Geosciences (Beijing), 2017.
[5] Saparin M A, Mustapha K A, Ismail M S. Biostratigraphy, organic petrography and carbon isotope chemostratigraphy of the Ordovician—Silurian black shales from the northwestern domain of Peninsular Malaysia[J]. International Journal of Coal Geology, 2023, 277: 104355. doi: 10.1016/j.coal.2023.104355
[6] Weinerová H, Bábek O, Slavík L, et al. Oxygen and carbon stable isotope records of the Lochkovian—Pragian boundary interval from the Prague Basin (lower Devonian, Czech Republic)[J]. Palaeogeography, Palaeoclimatology, Palaeoecology, 2020, 560: 110036. doi: https://doi.org/10.1016/j.palaeo.2020.110036
[7] Guo W, Ye F, Xu S, et al. Seasonal variation in sources and processing of particulate organic carbon in the Pearl River Estuary, South China[J]. Estuarine Coastal and Shelf Science, 2015, 167: 540−548. doi: 10.1016/j.ecss.2015.11.004
[8] Śliwiński M G, Whalen M T, Newberry R J, et al. Stable isotope (δ13Ccarb and org, δ15Norg) and trace element anomalies during the late Devonian ‘Punctata Event’ in the Western Canada Sedimentary Basin[J]. Palaeogeography, Palaeoclimatology, Palaeoecology, 2011, 307(1): 245−271. doi: https://doi.org/10.1016/j.palaeo.2011.05.024
[9] Bian J, Hou D, Cui Y, et al. Geochemical characteristics and origin of the ultra-deep hydrocarbons from the Shunbei Oilfield in the Tarim Basin, China: Insight from molecular biomarkers and carbon isotope geochemistry[J]. Marine and Petroleum Geology, 2023, 158: 106542. doi: https://doi.org/10.1016/j.marpetgeo.2023.106542
[10] Geske A, Zorlu J, Richter D K, et al. Impact of diagenesis and low grade metamorphosis on isotope (δ26Mg, δ13C, δ18O and 87Sr/86Sr) and elemental (Ca, Mg, Mn, Fe and Sr) signatures of Triassic Sabkha dolomites[J]. Chemical Geology, 2012, 332−333: 45−64. doi: 10.1016/j.chemgeo.2012.09.014
[11] Salminen P E, Karhu J A, Melezhik V A. Kolosjoki sedimentary formation: A record in the aftermath of the Paleoproterozoic global positive δ13C excursion in sedimentary carbonates[J]. Chemical Geology, 2013, 362: 165−180. doi: 10.1016/j.chemgeo.2013.10.018
[12] Xu S, Zhang Z, Jia G, et al. Controlling factors and environmental significance of BIT and δ13C of sedimentary GDGTs from the Pearl River Estuary, China over recent decades[J]. Estuarine, Coastal and Shelf Science, 2020, 233: 106534. doi: https://doi.org/10.1016/j.ecss.2019.106534
[13] 朱扬明, 郑霞, 刘新社, 等. 储层自生方解石碳同位素值应用于油气运移示踪[J]. 天然气工业, 2007(9): 24−27. doi: 10.3321/j.issn:1000-0976.2007.09.007 Zhu Y M, Zheng X, Liu X S, et al. Application of carbon isotope value of authigenic calcite in reservoir to hydrocarbon migration tracing[J]. Natural Gas Industry, 2007(9): 24−27. doi: 10.3321/j.issn:1000-0976.2007.09.007
[14] Zedgenizov D, Rubatto D, Shatsky V, et al. Eclogitic diamonds from variable crustal protoliths in the Northeastern Siberian craton: Trace elements and coupled δ13C−δ18O signatures in diamonds and garnet inclusions[J]. Chemical Geology, 2016, 422: 46−59. doi: 10.1016/j.chemgeo.2015.12.018
[15] Li X, Xie H, Birdwell J E, et al. Intramolecular carbon isotope geochemistry of butane isomers from laboratory maturation and Monte-Carlo simulations of kerogen types Ⅰ, Ⅱ, and Ⅲ[J]. Geochimica et Cosmochimica Acta, 2023, 360: 57−67. doi: 10.1016/j.gca.2023.09.003
[16] Mahanipour A, Mutterlose J, Kani A L, et al. Palaeoecology and biostratigraphy of early Cretaceous (Aptian) calcareous nannofossils and the δ13Ccarb isotope record from NE Iran[J]. Cretaceous Research, 2011, 32(3): 331−356. doi: 10.1016/j.cretres.2011.01.006
[17] Gocke M, Pustovoytov K, Kuehn P, et al. Carbonate rhizoliths in loess and their implications for paleoenvironmental reconstruction revealed by isotopic composition: δ13C, 14C[J]. Chemical Geology, 2012, 291: 294−295. doi: 10.1016/j.chemgeo.2011.10.012
[18] Zaccone C, Casiello G, Longobardi F, et al. Evaluating the ‘conservative’ behavior of stable isotopic ratios (δ13C, δ15N, and δ18O) in humic acids and their reliability as paleoenvironmental proxies along a peat sequence[J]. Chemical Geology, 2011, 285(1−4): 124−132. doi: 10.1016/j.chemgeo.2011.03.018
[19] Thibault N, Harlou R, Schovsbo N, et al. Upper Campanian—Maastrichtian nannofossil biostratigraphy and high-resolution carbon-isotope stratigraphy of the Danish Basin: Towards a standard δ13C curve for the Boreal Realm[J]. Cretaceous Research, 2012, 33(1): 72−90. doi: 10.1016/j.cretres.2011.09.001
[20] Feng L, Zhang Q. The pre-sturtian negative δ13C excursion of the Dajiangbian Formation deposited on the western margin of Cathaysia Block in South China[J]. Journal of Earth Science (Wuhan, China), 2016, 27(2): 225−232. doi: 10.1007/s12583-016-0665-9
[21] 卢凤艳, 安芷生. 鹤庆钻孔沉积物总有机碳、氮含量测定的前处理方法及其环境意义[J]. 地质力学学报, 2010, 16(4): 393−401. doi: 10.3969/j.issn.1006-6616.2010.04.007 Lu F Y, An Z S. Pretreatment method for determination of total organic carbon and nitrogen content in Heqing borehole sediments and its environmental significance[J]. Journal of Geomechanics, 2010, 16(4): 393−401. doi: 10.3969/j.issn.1006-6616.2010.04.007
[22] 曾花森, 霍秋立, 张晓畅, 等. 应用岩石热解数据S2-TOC相关图进行烃源岩评价[J]. 地球化学, 2010, 39(6): 574−579. doi: 10.19700/j.0379-1726.2010.06.007 Zeng H S, Huo Q L, Zhang X C, et al. Application of S2-TOC correlation diagram of rock pyrolysis data for hydrocarbon source rock evaluation[J]. Geochemistry, 2010, 39(6): 574−579. doi: 10.19700/j.0379-1726.2010.06.007
[23] 雷艳, 胡建芳, 向荣, 等. 末次盛冰期以来南海北部神狐海域沉积有机质的组成特征及其古气候/环境意义[J]. 海洋学报, 2017, 39(11): 75−84. doi: 10.3969/j.issn.0253-4193.2017.11.007 Lei Y, Hu J F, Xiang R, et al. Composition characteristics of sedimentary organic matter in Shenhu Sea area in the Northern South China Sea since the last glacial maximum and its paleoclimate/environmental significance[J]. Journal of Oceanography, 2017, 39(11): 75−84. doi: 10.3969/j.issn.0253-4193.2017.11.007
[24] 陈立雷, 张媛媛, 贺行良, 等. 海洋沉积物有机碳和稳定氮同位素分析的前处理影响[J]. 沉积学报, 2014, 32(6): 1046−1051. doi: 10.14027/j.cnki.cjxb.2014.06.006 Chen L L, Zhang Y Y, He X L, et al. Pretreatment effects of isotopic analysis of organic carbon and stable nitrogen in marine sediments[J]. Acta Sedimenta Sinica, 2014, 32(6): 1046−1051. doi: 10.14027/j.cnki.cjxb.2014.06.006
[25] Zhao G, Deng Q, Zhang H, et al. Trace elements and stable isotopic geochemistry of two sedimentary sections in the lower Cambrian strata from the Tarim Basin, Northwest China: Implications for silicification and biological evolution[J]. Marine and Petroleum Geology, 2023, 147: 105991. doi: 10.1016/j.marpetgeo.2022.105991
[26] 南君亚, 刘育燕. 浙江煤山二叠—三叠系界线剖面有机和无机碳同位素变化与古环境[J]. 地球化学杂志, 2004(1): 9−19. doi: 10.19700/j.0379-1726.2004.01.002 Nan J Y, Liu Y Y. Changes of organic and inorganic carbon isotopes in Permian—Triassic boundary profile in Jingshan Park, Zhejiang Province and paleoenvironment[J]. Journal of Geochemistry, 2004(1): 9−19. doi: 10.19700/j.0379-1726.2004.01.002
[27] 关成国, 王伟, 周传明. 湖北宜昌埃迪卡拉系陡山沱组下部无机碳同位素再研究: 探寻碳酸盐岩碳同位素组成的原始海水信号[J]. 地质学报, 2024, 98(3): 712−724. doi: 10.19762/j.cnki.dizhixuebao.2023277 Guan C G, Wang W, Zhou C M. Re-study of inorganic carbon isotopes in the lower part of Doushantuo Formation of Ediacaran system in Yichang, Hubei Province: Exploring the original seawater signal of carbon isotope composition of carbonate rocks[J]. Acta Geologica Sinica, 2024, 98(3): 712−724. doi: 10.19762/j.cnki.dizhixuebao.2023277
[28] 李超, 樊隽轩, 孙宗元. 奥陶系无机碳同位素地层学综述[J]. 地层学杂志, 2018, 42(4): 408−428. doi: 10.19839/j.cnki.dcxzz.2018.04.005 Li C, Fan J X, Sun Z Y. Overview of Ordovician inorganic carbon isotope stratigraphy[J]. Journal of Stratigraphy, 2018, 42(4): 408−428. doi: 10.19839/j.cnki.dcxzz.2018.04.005
[29] 于深洋. 黔东北志留纪早期的无机碳同位素地层和生物相-岩相[D]. 合肥: 中国科学技术大学, 2020. Yu S Y. Inorganic carbon isotope stratigraphy and bio-lithofacies of early Silurian in Northeastern Guizhou [D]. Hefei: China University of Science and Technology, 2020.
[30] 田涛, 周世新, 付德亮, 等. 米仓山—汉南隆起牛蹄塘组页岩稳定碳同位素组成及其意义[J]. 中国石油大学学报(自然科学版), 2019, 43(4): 40−51. doi: 10.3969/j.issn.1673-5005.2019.04.005 Tian T, Zhou S X, Fu D L, et al. Stable carbon isotope composition of shale in Niutitang Formation of Micangshan—Hannan Uplift and its significance[J]. Journal of China Petroleum University (Natural Science Edition), 2019, 43(4): 40−51. doi: 10.3969/j.issn.1673-5005.2019.04.005
[31] 胡广, 刘文汇, 罗厚勇, 等. 成烃生物组合对烃源岩干酪根碳同位素组成的影响: 以塔里木盆地下古生界烃源岩为例[J]. 矿物岩石地球化学通报, 2019, 38(5): 902−913. doi: 10.19658/j.issn.1007-2802.2019.38.133 Hu G, Liu W H, Luo H Y, et al. Influence of hydrocarbon-forming biological assemblage on carbon isotope composition of kerogen in source rocks: A case study of Lower Paleozoic source rocks in Tarim Basin[J]. Bulletin of Mineral Rock Geochemistry, 2019, 38(5): 902−913. doi: 10.19658/j.issn.1007-2802.2019.38.133
[32] 付修根, 王剑, 汪正江, 等. 藏北羌塘盆地胜利河油页岩干酪根特征及碳同位素指示意义[J]. 地球学报, 2009, 30(5): 643−650. doi: 10.3321/j.issn:1006-3021.2009.05.010 Fu X G, Wang J, Wang Z J, et al. Kerogen characteristics of Shengli River oil shale in Qiangtang Basin, Northern Tibet and its carbon isotope indication significance[J]. Acta Geoscientica Sinica, 2009, 30(5): 643−650. doi: 10.3321/j.issn:1006-3021.2009.05.010
[33] 常文博, 李凤, 张媛媛, 等. 元素分析-同位素值质谱法测量海洋沉积物中有机碳和氮稳定同位素组成的实验室间比对研究[J]. 岩矿测试, 2020, 39(4): 535−545. doi: 10.15898/j.cnki.11-2131/td.202003090027 Chang W B, Li F, Zhang Y Y, et al. Inter-laboratory comparison of stable isotopic compositions of organic carbon and nitrogen in marine sediments measured by elemental analysis-isotope ratio mass spectrometry[J]. Rock and Mineral Analysis, 2020, 39(4): 535−545. doi: 10.15898/j.cnki.11-2131/td.202003090027
[34] 徐丽, 邢蓝田, 王鑫, 等. 元素分析仪-同位素值质谱测量碳氮同位素值最佳反应温度和进样量的确定[J]. 岩矿测试, 2018, 37(1): 15−20. doi: 10.15898/j.cnki.11-2131/td.201701130005 Xu L, Xing L T, Wang X, et al. Determination of the optimal reaction temperature and sample size for measuring carbon-nitrogen isotope ratio by elemental analyzer-isotope ratio mass spectrometry[J]. Rock and Mineral Analysis, 2018, 37(1): 15−20. doi: 10.15898/j.cnki.11-2131/td.201701130005
[35] Brodie C R, Casford J S L, Lloyd J M, et al. Evidence for bias in C/N, δ13C and δ15N values of bulk organic matter, and on environmental interpretation, from a lake sedimentary sequence by pre-analysis acid treatment methods[J]. Quaternary Science Reviews, 2011, 30(21−22): 3076−3087. doi: 10.1016/j.quascirev.2011.07.003
[36] Nielsen C J S B. Effects of decarbonation treatments on δ13C value in marine sediments[J]. Marine Chemistry, 2000, 72(1): 55−59. doi: 10.1016/S0304-4203(00)00066-9
[37] 李秀美, 范宝伟, 侯居峙, 等. 青藏高原达则错沉积物有机碳同位素特征及古气候环境意义[J]. 地球科学, 2022, 47(6): 2275−2286. doi: 10.3799/dqkx.2021.167 Li X M, Fan B W, Hou J Z, et al. Isotopic characteristics of organic carbon in Dazecuo sediments in Qinghai—Tibet Plateau and its paleoclimatic and environmental significance[J]. Geoscience, 2022, 47(6): 2275−2286. doi: 10.3799/dqkx.2021.167
[38] 陆燕, 王小云, 曹建平. 沉积物中16种多环芳烃单体碳同位素GC-C-IRMS测试[J]. 石油实验地质, 2018, 40(4): 532−537. doi: 10.11781/sysydz201804532 Lu Y, Wang X Y, Cao J P. Determination of carbon isotopes of 16 polycyclic aromatic hydrocarbons in sediments by GC-C-IRMS[J]. Petroleum Experimental Geology, 2018, 40(4): 532−537. doi: 10.11781/sysydz201804532
[39] 刘颖, 孙惠玲, 周晓娟, 等. 过去5000a以来抚仙湖沉积物有机质碳同位素的古环境指示意义[J]. 湖泊科学, 2017, 29(3): 722−729. doi: 10.18307/2017.0322 Liu Y, Sun H L, Zhou X J, et al. Paleoenvironmental implications of carbon isotope of organic matter in sediments of Fuxian Lake since the past 5000a[J]. Lake Science, 2017, 29(3): 722−729. doi: 10.18307/2017.0322
[40] 杨盼盼. 哈拉湖沉积物有机碳同位素(δ13Corg)的环境指示意义[D]. 兰州: 兰州大学, 2021. Yang P P. Environmental implications of organic carbon isotope (δ13Corg) in sediments of Hala Lake [D]. Lanzhou: Lanzhou University, 2021.
[41] 耿悦, 吕喜玺, 于瑞宏, 等. 乌梁素海悬浮颗粒物和沉积物有机碳同位素特征及来源[J]. 湖泊科学, 2021, 33(6): 1753−1765. doi: 10.18307/2021.0612 Geng Y, Lyu X X, Yu R H, et al. Characteristics and sources of organic carbon isotopes of suspended particles and sediments in Wuliangsuhai Lake[J]. Lake Science, 2021, 33(6): 1753−1765. doi: 10.18307/2021.0612
[42] 胡志中, 晏雄, 金鹭, 等. 富有机质页岩氮同位素分析方法研究[J]. 岩矿测试, 2023, 42(4): 677−690. doi: 10.15898/j.ykcs.202212090231 Hu Z Z, Yan X, Jin L, et al. Study on nitrogen isotope analysis method for rich organic shale[J]. Rock and Mineral Analysis, 2023, 42(4): 677−690. doi: 10.15898/j.ykcs.202212090231
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