Organic Geochemistry最新文献

{"title":"Evolution of kerogen structure during the carbonization stage","authors":"Yu Liu ,&nbsp;Siyi Xie ,&nbsp;Guangjun Feng ,&nbsp;Chi Su ,&nbsp;Qiannan Xu ,&nbsp;Tengwei Gao","doi":"10.1016/j.orggeochem.2024.104743","DOIUrl":"https://doi.org/10.1016/j.orggeochem.2024.104743","url":null,"abstract":"<div><p>Currently, certain unconventional gas is mainly extracted from high-maturity shale reservoirs, but limited attention has been given to the evolution of kerogen structure subsequent to the overmature, gas generative stage, corresponding to metagenesis and is termed the carbonization stage. In this study, we performed heating treatment on overmature kerogen samples to obtain samples in the carbonization stage and then conducted Raman, thermogravimetric-mass spectrometric analysis (TG-MS), X ray diffraction (XRD), and high resolution transmission electron microscope (HRTEM) experiments on these samples to investigate the changes in kerogen structure. Low pressure N₂ and CO₂ adsorption experiments also were performed to investigate the changes in pore structure. The results show that as the heat treatment temperature is raised to 1000 °C, the I_D/I_G ratio (D band intensity to G band intensity) experiences an increase, reaching 1.12. Additionally, the full width at half maximum (FWHM) of 002 peak consistently remains above 3.8°. This suggests that these samples were matured to an early <em>meta</em>-anthracite (<em>meta</em>-kerogen) stage, which is significantly distant from the graphite stage. During this particular stage, the most obvious changes in molecular structure are the enlargement of aromatic clusters and the decrease in hydrogen atoms, and thus, H₂ rather than methane is produced, as revealed by the results of TC-MS experiment. Following an initial increase, the pore volume and surface area of kerogen samples decrease gradually, reaching their maximum values at 700 °C. Kerogen subjected to a heating temperature of 1000 °C exhibits a greater pore volume in comparison to the initial overmature kerogen. Thus, this observation provides evidence that shale kerogen in carbonization stage, which is typically lying at significant depths, holds promise as a viable reservoir for shale gas extraction.</p></div>","PeriodicalId":400,"journal":{"name":"Organic Geochemistry","volume":"190 ","pages":"Article 104743"},"PeriodicalIF":3.0,"publicationDate":"2024-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139936574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pyrolysis experiments of model compounds to explore carbon isotope fractionation in propane from natural gas","authors":"Wen Liu ,&nbsp;Yun Li ,&nbsp;Wenmin Jiang ,&nbsp;Ping'an Peng ,&nbsp;Yongqiang Xiong","doi":"10.1016/j.orggeochem.2024.104752","DOIUrl":"https://doi.org/10.1016/j.orggeochem.2024.104752","url":null,"abstract":"<div><p>Investigating the mechanisms that determine the bulk and position-specific carbon isotopic distributions of propane in natural gas will help elucidate its formation and evolution. We used octadecane and squalane as model compounds that give simple precursors for gas production in gold-tube isothermal pyrolysis experiments to study the variations in intermolecular and intramolecular distributions of isotopes in the generated gaseous hydrocarbons. The δ¹³C values of the products and inverses of their carbon numbers (1/<em>n</em> where <em>n</em> = C₁–C₅) showed a negative linear relationship versus maturity, indicating that they formed by homolytic cleavage of C–C bonds and that the precursors showed homogeneous distributions of carbon isotopes. However, the significant difference in the kinetic isotopic effects (KIEs) of the gas generated by cracking of two model compounds under the same experimental conditions is not readily explained by single homolytic bond cleavage. The results indicate that besides the KIE of C–C bond cleavage, the bulk and position-specific carbon isotopic compositions of propane are related to the chemical and isotopic structures of the precursors and the propane transformation ratio. Based on the sites of C–C bond cleavage, two isotopic fractionation patterns (i.e., normal propyl and isopropyl models) may explain the bulk and position-specific carbon isotopic distributions of the generated propane. According to the propyl model, propane originates from (normal) propyl structures (CH₃CH₂CH₂*) in the precursor via C–C bond cleavage at a terminal site of a propyl group, while the isopropyl model involves propane derived from isopropyl structures (CH₃CH*CH₃) in the precursor, with C–C bond cleavage at the central site. Simulations show that these distributions for propane cracked from octadecane closely follow the propyl model, whereas propane generated from squalane showed mixed contributions from both models, and its bulk and position-specific carbon isotopic distributions depend on the proportions of propyl and isopropyl structures in the precursors. Variations of propane’s position-specific carbon isotopic distributions during the main stage of propane generation indicate that free radical reactions are the main pathway for thermogenic propane formation, resulting in similar KIEs for propane terminal and central carbons. Therefore, the position-specific carbon isotopic distribution of propane can provide evidence of its formation mechanism and shows potential for revealing the origin and evolution of natural gas.</p></div>","PeriodicalId":400,"journal":{"name":"Organic Geochemistry","volume":"189 ","pages":"Article 104752"},"PeriodicalIF":3.0,"publicationDate":"2024-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139732501","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantification of allochthonous and autochthonous organic carbon in large and shallow Lake Wuliangsu based on distribution patterns and δ13C signatures of n-alkanes","authors":"Qingfeng Zhao ,&nbsp;Aifeng Zhou ,&nbsp;Yuxin He","doi":"10.1016/j.orggeochem.2024.104754","DOIUrl":"https://doi.org/10.1016/j.orggeochem.2024.104754","url":null,"abstract":"<div><p>Identification and quantification of allochthonous and autochthonous organic carbon (OC) in large and shallow lakes are crucial for knowledge of OC burial and recycling behaviors, as well as sustainable management practices. However, quantitative methods to estimate the contributions from various OC sources are still limited. In this study, we analyzed distribution patterns and δ¹³C signatures of mid- and long-chain <em>n</em>-alkanes from aquatic plants, riverine sediment, and surface sediments from a typically large and shallow Lake Wuliangsu in the Hetao Irrigation District, China. The results indicate that <em>n</em>-alkanes among submerged macrophytes, emergent plants, and riverine sediment show unique distribution patterns and δ¹³C signatures, supporting the practicability of identification and quantification of OC sources by end-member mixing models of <em>n</em>-alkanes’ distribution patterns and ¹³C values. Our results also suggest that introducing δ¹³C values into the end-member mixing models could effectively reduce the uncertainty, as <em>n</em>-alkane distribution patterns might be modified by different species, habitat environments, and potential OC degradation. In the case of Lake Wuliangsu, the model results demonstrate that the riverine sourced OC from the main channel has decreased during southward transport, indicating that Lake Wuliangsu serves as an important trap and sink for OC transported from the upper reaches of the Yellow River. The model results also show a predominant contribution of the autochthonous OC to sediments in Lake Wuliangsu, with open-water areas dominated by submerged macrophyte-sourced OC and the other areas by emergent plant-sourced OC. Higher productivities of submerged macrophytes are mainly modulated by increases in water depth, water transparency, and nutrient concentrations, while higher productivities of emergent plants are mainly associated with increasing nutrient concentrations. To improve the ecological conditions and OC burial of Lake Wuliangsu, it is necessary to manage the quality of the inflowing water from the agricultural farmland, as well as the preservation of the water body from current paludification.</p></div>","PeriodicalId":400,"journal":{"name":"Organic Geochemistry","volume":"189 ","pages":"Article 104754"},"PeriodicalIF":3.0,"publicationDate":"2024-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139744210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geochemistry Articles – December 2023","authors":"","doi":"10.1016/j.orggeochem.2024.104738","DOIUrl":"10.1016/j.orggeochem.2024.104738","url":null,"abstract":"","PeriodicalId":400,"journal":{"name":"Organic Geochemistry","volume":"188 ","pages":"Article 104738"},"PeriodicalIF":3.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139556144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"GEOCHEMISTRY ARTICLES – November 2023","authors":"","doi":"10.1016/j.orggeochem.2024.104737","DOIUrl":"10.1016/j.orggeochem.2024.104737","url":null,"abstract":"","PeriodicalId":400,"journal":{"name":"Organic Geochemistry","volume":"188 ","pages":"Article 104737"},"PeriodicalIF":3.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139556539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Variations in microbial residue carbon and its contribution to soil organic carbon after vegetation restoration on farmland: The case of Guinan County","authors":"Na Li ,&nbsp;Yalin Wang ,&nbsp;Lin Wei ,&nbsp;Xungang Wang ,&nbsp;Qian Zhang ,&nbsp;Tongqing Guo ,&nbsp;Xianli Xu ,&nbsp;Na Zhao ,&nbsp;Shixiao Xu","doi":"10.1016/j.orggeochem.2024.104753","DOIUrl":"10.1016/j.orggeochem.2024.104753","url":null,"abstract":"<div><p>Microbial residue carbon (C) serves as a significant source of soil organic carbon (SOC). However, the contribution of microbial residue C to SOC accumulation after the restoration of farmland vegetation remains unclear, making it challenging to comprehend the role of microorganisms in the accumulation and transformation of SOC after vegetation restoration on farmland. Based on field investigations in Guinan County, Qinghai Province, our study focused on the microbial residue C content and its contribution to SOC in farmland, grassland, and shrub forest, employing the analysis of biomarkers. The results indicated that the microbial residue C content increased with the rise of SOC, soil total nitrogen (STN), and enzyme activities. Compared to farmland, grassland displayed significantly lower levels of SOC and STN, leading to reduced microbial residue C content, notably impacting the C content of fungal residues. Despite slightly lower levels of SOC and STN compared to farmland, shrub forest exhibited higher soil microbial residue C content, notably within bacterial residue C, due to elevated soil enzyme activities. The contribution of microbial residue C to SOC decreased as SOC content increased. In farmland boasting higher SOC content, the contribution of microbial residue C to SOC was notably lower compared to shrub forest and grassland with lower SOC content. In conclusion, compared to farmland, both shrub forest and grassland exhibited higher contributions of microbial residue C to SOC, which is favorable for the sequestration of stable SOC.</p></div>","PeriodicalId":400,"journal":{"name":"Organic Geochemistry","volume":"189 ","pages":"Article 104753"},"PeriodicalIF":3.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0146638024000184/pdfft?md5=208e99a95198a4f1700ecffab9a6ccef&pid=1-s2.0-S0146638024000184-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139663063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intramolecular carbon isotopic rollover in propane from natural gas reservoirs of the Santanghu Basin: Insights into chemical structure of kerogen","authors":"Peng Liu ,&nbsp;Xiaofeng Wang ,&nbsp;Changjie Liu ,&nbsp;Ying Lin ,&nbsp;Ruiliang Guo ,&nbsp;Wenhui Liu","doi":"10.1016/j.orggeochem.2024.104740","DOIUrl":"https://doi.org/10.1016/j.orggeochem.2024.104740","url":null,"abstract":"<div><p>An intramolecular isotopic study was conducted on natural gases from the Santanghu Basin in China. Propane samples spanned a wide range of Δ_C-T (δ¹³C_central-δ¹³C_terminal) values from –8.4 to 8.5 ‰, δ¹³C_central and δ¹³C_terminal values varied from –37.3 to –25.8 ‰ and –35.7 to –28.9 ‰, respectively. During thermal maturation, the position-specific carbon isotopic composition of propane shifted from δ¹³C_central &lt; δ¹³C_terminal to δ¹³C_central &gt; δ¹³C_terminal, and the δ¹³C_terminal decreased by 6.8 ‰ within a R_o range of 0.46–0.50 %. The intramolecular carbon isotopic rollover and a decrease in δ¹³C_terminal with a slight increase in maturation could be explained by kinetic effects in thermal cracking of kerogen with a low proportion of branched chains. As isomeric groups were rapidly exhausted, propane generation pathway rapidly changed and primary kinetic isotope effect completely shifted from central carbon position to terminal carbon positions in propane. These changes increased carbon isotope fractionation at terminal carbon positions, thereby reducing δ¹³C_terminal values and shifting δ¹³C_central &lt; δ¹³C_terminal to δ¹³C_central &gt; δ¹³C_terminal within a small maturity range. This work demonstrated that position-specific isotope distribution of propane can be applied to elucidate the chemical structure of kerogen.</p></div>","PeriodicalId":400,"journal":{"name":"Organic Geochemistry","volume":"188 ","pages":"Article 104740"},"PeriodicalIF":3.0,"publicationDate":"2024-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139550014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular transformations of heteroatomic organic compounds in crude oils caused by biodegradation and subsequent thermal maturation: Insights from ESI FT-ICR MS","authors":"Bin Jiang ,&nbsp;Weimin Liu ,&nbsp;Yuhong Liao ,&nbsp;Ping'an Peng","doi":"10.1016/j.orggeochem.2024.104741","DOIUrl":"https://doi.org/10.1016/j.orggeochem.2024.104741","url":null,"abstract":"<div><p>The Tarim and Junggar basins are major petroliferous sedimentary deposits in China. Some oil reservoirs in these basins experienced superimposed secondary alterations including early biodegradation followed by thermal maturation/alteration (SSA-B&amp;M). Heteroatomic polar organic compounds in crude oil are significantly influenced by SSA-B&amp;M, which play a vital role in understanding the evolutionary history of oil reservoir. However, research on such alterations is limited. The present study employed negative and positive ion electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS) to investigate the molecular transformations of heteroatomic organic compounds in crude oils resulting from SSA-B&amp;M. The findings indicate that biodegradation leads to an enrichment of naphthenic acids, while subsequent cyclization, aromatization and thermal cracking reactions enhances the aromaticity of the pyrolysis products of all the oil samples with varying degree of biodegradation. Notably, highest aromaticity was observed for the crude oil that has been most severely altered by biodegradation. During early and moderate stages of biodegradation, the abundances of O2 compounds (molecules contain two oxygen atoms) representing carboxylic acids were continuously increasing. However, at severe biodegradation levels, fatty acids with 1 double bond equivalents (DBE) underwent degradation, while the naphthenic acids were further enriched. Subsequently, during maturation, O2 compounds with 1 to 5 DBE experienced a steady decline in abundance. The naphthenic acids mainly experienced aromatization, while the fatty acids were partly decarboxylized and cracked thereby forming new n-alkanes. Biodegradation led to modification in neutral nitrogen compounds with 3 to 4 condensed rings (DBE = 9–12) and long alkyl side chains, while the impact on basic nitrogen compounds was relatively minimal. After subsequent thermal maturation, both neutral and basic nitrogen compounds with long alkyl side chains underwent cracking, while those with shorter alkyl side chains and higher degrees of condensation tended to remain relatively unchanged. Finally, two new indices were defined and tested to correctly evaluate the maturation and biodegradation level for crude oils that have experienced SSA-B&amp;M.</p></div>","PeriodicalId":400,"journal":{"name":"Organic Geochemistry","volume":"188 ","pages":"Article 104741"},"PeriodicalIF":3.0,"publicationDate":"2024-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139503497","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The bacterial influencing mechanisms of salinity fluctuations in a brackish-water lake on the dissolved organic matter characteristics of pore water","authors":"Lei Xie ,&nbsp;Dezhi Zuo ,&nbsp;Yushen Ma ,&nbsp;Xiang Zhu ,&nbsp;Bin Xu ,&nbsp;Fei He ,&nbsp;Qingqing Pang ,&nbsp;Longmian Wang ,&nbsp;Fuquan Peng ,&nbsp;Lixiao Ni ,&nbsp;Wenjuan Jiang ,&nbsp;Haibo Dong","doi":"10.1016/j.orggeochem.2024.104744","DOIUrl":"10.1016/j.orggeochem.2024.104744","url":null,"abstract":"<div><p>The dissolved organic matter (DOM) components in lake water have been widely studied; however, few previous studies have considered the growth of <em>Phragmites australis</em> in brackish lakes. It has not been well understood how salinity variations influence the DOM compositions in pore water and its bacterial mechanisms in lakes with <em>Phragmites australis</em>. This experiment included three salinity groups (1,200 mg/L, 3,600 mg/L, and 6,000 mg/L) to study the interactions between bacteria and DOM in pore water under a salinity gradient. The results showed that the maximum fluorescence intensity (F_max) of DOM measured by excitation-emission fluorescence spectroscopy decreased with increasing salinity. Higher salinity reduced the F_max of protein-like substances and resulted in DOM becoming more aromatic. Salinity affected DOM composition due to the responses of functional bacterial communities. <em>Thiobacillus</em> was salt-tolerant and dominated in the sediments, and its relative abundance was negatively correlated with the F_max of protein-like components. The relative abundance of <em>Flavobacterium</em> showed a positive correlation with salinity and a negative correlation with the F_max of the fulvic acid-like component. <em>Pseudomonas</em>, <em>Brevundimonas</em>, and <em>Polaromonas</em> were negatively correlated with salinity and the F_max of the fulvic acid-like component, while being positively correlated with the F_max of tyrosine-like and aromatic protein substances. Higher salinity inhibited the metabolism gene modules of tryptophan and tyrosine. The results of this study may offer a novel perspective on comprehending the biochemical cycling of fluorescent DOM, encompassing tryptophan-like, tyrosine-like, and fulvic acid-like components in brackish lakes with fluctuating salinity.</p></div>","PeriodicalId":400,"journal":{"name":"Organic Geochemistry","volume":"189 ","pages":"Article 104744"},"PeriodicalIF":3.0,"publicationDate":"2024-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139506710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seasonal temperature dependency of aquatic branched glycerol dialkyl glycerol tetraethers: A mesocosm approach","authors":"Fatemeh Ajallooeian ,&nbsp;Longhui Deng ,&nbsp;Mark Alexander Lever ,&nbsp;Cindy De Jonge","doi":"10.1016/j.orggeochem.2024.104742","DOIUrl":"10.1016/j.orggeochem.2024.104742","url":null,"abstract":"<div><p>BrGDGTs, membrane-spanning lipids produced by bacteria, are at the basis of the MBT’_5ME, a biomarker ratio that has been used as a paleotemperature proxy. However, the response of the MBT’_5ME to temperature changes, particularly in freshwater systems, remains incompletely understood. In this study, oxic mesocosms are used to assess the temperature sensitivity of brGDGTs and their producers, sampled from a lake (Lake Rot) and a river (Sihl River) in three different seasons. Three temperature treatments are employed (10, 17.5, and 25 ℃), representing control (in-situ temperatures), cooling, and/or warming treatments, with GDGTs and the bacterial community measured at several timepoints (24 h, 1, 2, 3 and 5 weeks). The control experiments showed that this experimental approach could not replicate natural conditions exactly, with small changes in chemistry (pH, conductivity, alkalinity) and bacterial community composition. Still, our mesocosm setup yielded valuable insights into the temperature-dependent production of lacustrine brGDGTs and MBT’_5ME values, especially in warming treatments, while no response was observed in cooling treatments, potentially indicating limited sensitivity to cold temperatures. In the river mesocosms not the MBT’_5ME but the IR ratio showed a temperature dependency, potentially driven by small changes in the water pH. Coeval changes in the composition of the bacterial community and the MBT’_5ME and IR are determined to constrain potential GDGT producers. Although an increase in MBT’_5ME in response to some warming incubations is observed, the temperature-sensitivity of MBT’_5ME, as expected from GDGT studies on a global scale, is not supported by this experiment.</p></div>","PeriodicalId":400,"journal":{"name":"Organic Geochemistry","volume":"189 ","pages":"Article 104742"},"PeriodicalIF":3.0,"publicationDate":"2024-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S014663802400007X/pdfft?md5=a954aeb3d0641d6b6cdd27ad7a39b40c&pid=1-s2.0-S014663802400007X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139499368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}