Characteristics of Gravity and Magnetic Field and their Significance of Helium Resources Exploration in the Southeastern Ordos Basin
-
摘要:
氦气作为一种稀有气体,广泛应用于国防军工、高新技术产业发展等领域,关系到国家的安全与发展。中国氦气资源短缺,对外依赖程度高。鄂尔多斯盆地内展现出了较好的氦气资源前景,但对与氦气分布密切相关的氦源岩及断裂特征研究较少,制约了对盆地氦气资源潜力的认识。笔者利用归一化总水平导数垂向导数(NVDR−THDR)、垂向导数、位场分离等技术对鄂尔多斯盆地东南部的重磁资料进行处理,推断主要断裂和潜在的氦源岩(强磁性变质岩)。鄂尔多斯盆地东南部氦气分布受基底断裂与氦源岩分布的双重控制,基底强磁性变质岩为盆地内部的氦气富集提供气源条件,断裂活动则为氦气运移提供通道。富县−宜川−黄龙一带分布有大量的强磁性变质岩,大多位于断裂附近及其交汇区域,可能是氦气资源潜在有利区。
Abstract:Helium is widely used in the fields of national defense, military industry, high−tech industry development and so on, as a rare gas related to the national security and development. China is short of helium resources and highly dependent on foreign countries. There is a good prospect of helium resources in Ordos basin. However, there are fewer study on the characteristics of the helium source rocks and the faults related closely to the helium distribution, which limits the evaluation of the helium resource potential in the basin. In this thesis, the gravity and magnetic data in the southeast of Ordos basin are processed by using the normalized vertical derivative of the total horizontal derivative (NVDR−THDR), vertical derivative and potential field date separation techniques, and inferred the main faults and potential helium source rocks (strong magnetic metamorphic rocks). The distribution of helium resources is controlled by the basement faults and the distribution of helium source rocks. The strong magnetic metamorphic rocks provide gas source conditions for helium enrichment in the basin, and fault activity provides channels for helium migration. There are a large number of metamorphic rocks distributed in Fuxian−Yichuan−Huanglong area. Most of them are located near faults and their intersection areas, which may be potential favorable areas for helium resources.
-
Key words:
- helium resources /
- gravity and magnetic anomaly /
- metamorphic rock /
- faults /
- Ordos basin
-
地层/岩体 岩石密度ρ(g/cm3) 磁化率(10−5 SI) 密度值 平均值 密度值 平均值 新生界 第四系 1.63~2.10 1.87 36~79 56 古近系
新近系2.30~2.39 2.38 5~13 9.6 中生界 白垩系 2.40 10.5~58.9 18.6 侏罗系 2.41~2.44 2.43 6.5~17.3 10.5 三叠系 2.55 8.8~18.6 15.3 古生界 二叠系 2.60 2.5~22.0 16.3 石炭系 3.2~20.8 9.6 奥陶系 2.70 5.6~14.6 8.8 寒武系 10.5~16.8 12.7 元古界 2.70 5.4~9.2 7.8 太古界 变粒岩 2.76 1300~10600 5600 片麻岩 8.6~1400 780 混合岩 10.5~16.8 13.6 大理岩 11.6~245 18.4 侵入岩 闪长岩 2.5~3.3 40~9545 5332 花岗闪长岩 2.56 2.56 1374.18 花岗岩 2.58 0~6048 3206 玄武岩 2.8~3.3 2.69 10~2713 1250 二长石 2.47~2.71 2.59 771.16 -
[1] 包洪平, 邵东波, 郝松立, 等. 鄂尔多斯盆地基底结构及早期沉积盖层演化[J]. 地学前缘(中国地质大学(北京); 北京大学), 2019, 26(01): 33-43
BAO Hongping, SHAO Dongbo, HAO Songli, et al. Basement Structure and Evolution of Early Sedimentary Cover of the Ordos Basin[J]. Earth Science Frontiers (China University of Geosciences (Beijing); Peking University), 2019, 26(01): 33-43.
[2] 陈道公, 倪涛. 大别-苏鲁造山带高级变质岩中锆石微区U, Th和Pb化学组成特征统计[J]. 岩石学报, 2004, 20(5): 8
CHEN Daogong, NI Tao. Zircon U, Th and Pb Characteristics of High-Grade Metamorphic Rocks from Dabie-Sulu Orogen[J]. Acta Petrologica Sinica, 2004, 20(5): 8.
[3] 晁海德, 陈建洲, 王国仓, 等. 柴达木盆地水溶氦气资源的发现及富集机理[J]. 西北地质, 2022, 55(4): 61−73.
CHAO Haide, CHEN Jianzhou, WANG Guocang, et al. Discovery and Enrichment Mechanism of Water Soluble Helium Resources in Qaidam Basin[J]. Northwestern Geology, 2022, 55(4): 61−73.
[4] 戴金星, 李剑, 侯路. 鄂尔多斯盆地氦同位素的特征[J]. 高校地质学报, 2005, 11(04): 473-478 doi: 10.3969/j.issn.1006-7493.2005.04.002
DAI Jinxing, LI Jian, HOU Lu. Characteristics of Helium Isotopes in the Ordos Basin[J]. Geological Journal of China Universities, 2005, 11(04): 473-478. doi: 10.3969/j.issn.1006-7493.2005.04.002
[5] 何登发, 包洪平, 开百泽, 等. 鄂尔多斯盆地及其邻区关键构造变革期次及其特征[J]. 石油学报, 2021, 42(10): 1255-1269 doi: 10.7623/syxb202110001
HE Dengfa, BAO Hongping, KAI Baize, et al. Critical Tectonic Modification Periodls and its Geologic Features of Ordos Basin and Adjacent Area[J]. Acta Petrolei Sinica, 2021, 42(10): 1255-1269. doi: 10.7623/syxb202110001
[6] 何发岐, 王付斌, 王杰, 等. 鄂尔多斯盆地东胜气田氦气分布规律及特大型富氦气田的发现[J]. 石油实验地质, 2022, 44(1): 10
HE Faqi, WANG Fubin, WANG Jie et al. Helium Distribution of Dongsheng Gas Field in Ordos Basin and Discovery of a Super Large Helium-Rich Gas Field[J]. Petroleum Geology & Experiment, 2022, 44(1): 10.
[7] 何紫娟. 重磁综合处理解释在鄂尔多斯区域构造中的应用研究[D]. 北京: 中国地质大学, 2013
HE Zijuan. The Application of Gravity and Magnetic Data Processing and Interpretation in Regional Tectonic Analysis of Ordos Basin. [D]. Beijing: China University of Geosciences, 2013.
[8] 贺政阳, 杨国军, 周俊林, 等. 柴达木盆地北缘天然气中氦气富集规律与远景区预测[J]. 西北地质, 2022, 55(4): 45-60 doi: 10.19751/j.cnki.61-1149/p.2022.04.004
HE Zhengyang, YANG Guojun, ZHOU Junlin, et al. Helium Enrichment Law and Predication of Prospective Areas of the North Qaidam Basin[J]. Northwestern Geology, 2022, 55(4): 45-60. doi: 10.19751/j.cnki.61-1149/p.2022.04.004
[9] 黄志刚, 任战利, 高龙刚. 鄂尔多斯盆地东南缘白垩纪以来构造演化的裂变径迹证据[J]. 地球物理学报, 2016, 59(10): 3753-3764.
HUANG Zhigang, REN Zhanli, GAO Longgang. Evidence from Detrital Zircon and Apatite Fission Track for Tectonic Evolution since Cretaceous in Southeastern Margin of Ordos Basin[J]. Chinese Journal of Geophys, 2016, 59(10): 3753- 3764.
[10] 纪晓琳, 王万银, 杜向东, 等. 利用重磁资料研究西非中南段含盐盆地构造区划[J]. 地球物理学报, 2019, 62(04): 1502-1514 doi: 10.6038/cjg2019L0573
JI Xiaolin, WANG Wanyin, DU Xiangdong, et al. Tectonic Division by Gravity and Magnetic Anomaly Data of Salt-bearing Basins, South-Central Section of West Africa[J]. Chinese J. Geophys. (in Chinese), 2019, 62(04): 1502-1514. doi: 10.6038/cjg2019L0573
[11] 贾凌霄, 马冰, 王欢, 等. 全球氦气勘探开发进展与利用现状[J]. 中国地质, 2022, 49(05): 1427-1437
JIA Lingxiao, MA Bing, WANG Huan, et al. Progress and Utilization Status of Global Helium Exploration and Development[J]. Geology in China, 2022, 49(05): 1427-1437.
[12] 李冰, 宋燕兵, 石磊, 等. 鄂尔多斯盆地的磁场特征及地质意义[J]. 物探与化探, 2019, 43(4): 767-777
LI Bing, SONG Yanbing, SHI Lei, et al. Characteristics of Gravity and Magnetic Fields in Ordos Basin and their Geological Significance[J]. Geophysical and Geochemical Exploration, 2019, 43(4): 767-777.
[13] 李明, 高建荣. 鄂尔多斯盆地基底断裂与火山岩的分布[J]. 中国科学: 地球科学, 2010, 40(08): 1005-1013
LI Ming, GAO Jianrong. Basement Faults and Volcanic Rock Distributions in the Ordos Basin[J]. Sci China: Earth Sci, 2010, 40(08): 1005-1013.
[14] 李明, 闫磊, 韩绍阳. 鄂尔多斯盆地基底构造特征[J]. 吉林大学学报(地球科学版), 2012, 42(S3): 38-43
LI Ming, YAN Lei, HAN Shao Yang. The Basement Tectonic Characteristics in Ordos Basin[J]. Journal of Jilin University( Earth Science Edition), 2012, 42(S3): 38-43.
[15] 李玉宏, 王行运, 韩伟. 陕西渭河盆地氦气资源赋存状态及其意义[J]. 地质通报, 2016, 35(2/3): 372-378
LI Yuhong, WANG Xingyun, HAN Wei. Mode of Occurrence of Helium in Weihe Basin, Shanxi Province and its Significance[J]. Geological Bulletin of China, 2016, 35(2/3): 372-378.
[16] 李玉宏, 张国伟, 周俊林, 等. 氦气资源调查理论与技术研究现状及建议[J]. 西北地质, 2022, 55(4): 1-10
LI Yuhong, ZHANG Guowei, ZHOU Junlin, et al. Research Status and Suggestions on Helium Resource Investigation Theory and Technology[J]. Northwestern Geology, 2022, 55(4): 1-10.
[17] 李玉宏, 卢进才, 李金超, 等. 渭河盆地富氦天然气井分布特征与氦气成因[J]. 吉林大学学报(地球科学版), 2011, 41(S1): 47-53
LI Yuhong, LU Jincai, LI Jinchao, et al. Distribution of the Helium-Rich Wells and Helium Derivation in Weihe Basin[J]. Journal of Jilin University(Earth Science Edition), 2011, 41(S1): 47-53.
[18] 刘超, 孙蓓蕾, 曾凡桂, 等. 鄂尔多斯盆地东缘石西区块含氦天然气的发现及成因初探[J]. 煤炭学报, 2021, 46(04): 1280-1287
LIU Chao, SUN Bei Lei, ZENG Fangui, et al. Discovery and Origin of Helium-Rich Gas on the Shixi area, Eastern Margin of the Ordos Basin[J]. Journal of China Coal Society, 2021, 46(04): 1280-1287.
[19] 刘凯旋, 陈践发, 付娆, 等. 威远气田富氦天然气分布规律及控制因素探讨[J]. 中国石油大学学报(自然科学版), 2022, 46(4): 12-21
LIU Kaixuan, CHEN Jianfa, FU Rao, et al. Discussion on distribution law and controlling factors of helium-rich natural gas in Weiyuan gas field[J]. Journal of China University of Petroleum(Edition of Natural Science), 2022, 46(4): 12-21.
[20] 路利春, 赵炳坤, 周明霞, 等. 高精度重磁测量在渭河盆地氦气调查中的应用研究[J]. 陕西地质, 2017, 35(02): 52-59 doi: 10.3969/j.issn.1001-6996.2017.02.009
LU Lichun, ZHAO Bingkun, ZHOU Mingxia, et al. High Precision Gravity and Magnetism Measurement Used in Helium Gas Investigation at the Weihe River Basin[J]. Geology of Shaanxi, 2017, 35(02): 52-59. doi: 10.3969/j.issn.1001-6996.2017.02.009
[21] 马涛, 朱莹洁, 杨永等. 基于重磁异常的嘉偕平顶山群构造区划特征研究[J]. 物探与化探, 2020, 44(04): 938-948
MA Tao, ZHU Yingjie, YANG Yong, et al. Research on Tectonic Division in Jiaxie Guyots Based on Gravity and Magnetic Anomalies[J]. Geophysical & Geochemical Exploration, 2020, 44(04): 938-948.
[22] 孟军海, 马龙, 王金海, 等. 重力数据在德令哈地区区域性综合解释中的开发应用研究[J]. 物探与化探, 2021, 45(02): 369-378.
MENG Junhai, MA Long, WANG Jinhai, et al. The Development and Application of Gravity Data in Regional Comprehensive Interpretation of Delingha Region[J]. Geophysical&Geochemical Exploration, 2021, 45(02) : 369- 378.
[23] 密文天, 陈安清, 张成弓, 等. 鄂尔多斯盆地富县上三叠统长8段砂体分布及成因模式[J]. 科学技术与工程, 2016, 16(29): 13-19 doi: 10.3969/j.issn.1671-1815.2016.29.003
MI Wentian, CHEN Anqing, ZHANG Chenggong, et al. Sandbody’s Distribution and Genetic Model of Member Chang-8 of Yanchang Formation of Upper Triassic, Fuxian Area in Ordos Basin[J]. Science Technology and Engineering, 2016, 16(29): 13-19. doi: 10.3969/j.issn.1671-1815.2016.29.003
[24] 宁媛丽, 周子阳, 孙栋华. 重磁资料在鄂尔多斯盆地西南缘基底研究中的应用[J]. 物探与化探, 2020, 44(01): 34-41
NING Yuanli, ZHOU Ziyang, SUN Donghua. The Application of Magnetic and Gravity Data on Research the Basement in the Southwest of Ordos Basin[J]. Geophysical & Geochemical Exploration, 2020, 44(01): 34-41.
[25] 任战利, 崔军平, 李进步, 等. 鄂尔多斯盆地渭北隆起奥陶系构造-热演化史恢复[J]. 地质学报, 2014, 88(11): 2044-2056
REN Zhanli, CUI Junping, LI Jinbu, et al. Tectonic Thermal History Reconstruction of Ordovician in the Weibei Uplift of Ordos Basin[J]. Acta Geologica Sinica, 2014, 88(11): 2044-2056.
[26] 司庆红, 曾威, 刘行, 等. 临汾–运城盆地氦气富集要素及成藏条件[J]. 西北地质, 2023, 56(1): 129−141.
SI Qinghong, ZENG Wei, LIU Xing, et al. Analysis of Helium Enrichment Factors and Reservoir Forming Conditions in Linfen–Yuncheng Basin[J]. Northwestern Geology, 2023, 56(1): 129−141.
[27] 孙建博, 孙兵华, 赵谦平, 等. 鄂尔多斯盆地富县地区延长组长7湖相页岩油地质特征及勘探潜力评价[J]. 中国石油勘探, 2018, 23(06): 29-37 doi: 10.3969/j.issn.1672-7703.2018.06.004
SUN Jianbo, SUN Binghua, ZHAO Qianping, et al. Geological Characteristics and Exploration Potential Evaluation of Chang 7 Lacustrine Shale Oil in Yanchang Formation, Fuxian area, Ordos Basin[J]. China Petroleum Exploration, 2018, 23(06): 29-37. doi: 10.3969/j.issn.1672-7703.2018.06.004
[28] 孙晓, 王杰, 陶成, 等. 鄂尔多斯盆地大牛地下古生界天然气地球化学特征及其来源综合判识[J]. 石油实验地质, 2021, 43(02): 307-314 doi: 10.11781/sysydz202102307
SUN Xiao, WANG Jie, TAO Cheng, et al. Evaluation of Geochemical Characteristics and Source of Natural Gas in Lower Paleozoic, Daniudi Area, Ordos Basin[J]. Petroleum Geology & Experiment, 2021, 43(02): 307-314. doi: 10.11781/sysydz202102307
[29] 汤超. 鄂尔多斯盆地东北部砂岩型铀矿元素地球化学[D]. 北京: 中国地质大学, 2014
TANG Chao. Elements Geochemistry of Sandstone Type Uranium Deposit, Northeast Ordos Basin[D]. Beijing: China University of Geosciences, 2014.
[30] 陶小晚, 李建忠, 赵力彬, 等. 我国氦气资源现状及首个特大型富氦储量的发现: 和田河气田[J]. 地球科学, 2019, 44(03): 1024-1041
TAO XiaoWan, LI JianZhong, ZHAO LiBin, et al. Helium Resources and Discovery of First Supergiant Helium Reserve in China: Hetianhe Gas Field[J]. Earth science, 2019, 44(03): 1024-1041.
[31] 王万银, 王云鹏, 李建国, 等. 利用重、磁资料研究于都—赣县矿集区盘古山地区断裂构造及花岗岩体分布[J]. 物探与化探, 2014, 38(04): 825-834
WANG Wanyin, WANG Yunpeng, LI Jianguo, et al. Study on the Faults Structure and Granite Body Distribution in Pangushan Area of Yudu-Ganxian Ore District Using Gravity and Magnetic Data[J]. Geophysical & Geochemical Exploration, 2014, 38(04): 825-834.
[32] 王学发, 王万银, 马杰, 等. 基于重力资料的马达加斯加岛及邻区盆地构造单元分布特征[J]. 物探与化探, 2020, 44(04): 928-937
WANG Xuefa, WANG Wanyin, MA Jie, et al. A Study of the Distribution Characteristics of Basin Tectonic Units Based on Gravity Data in Madagascar and its Adjacent Basins[J]. Geophysical& Geochemical Exploration, 2020, 44(04): 928-937.
[33] 魏国齐, 朱秋影, 杨威, 等鄂尔多斯盆地寒武纪断裂特征及其对沉积储集层的控制[J]. 石油勘探与开发, 2019, 46(05): 836-847
WEI Guoqi, ZHU Qiuying, YANG Wei, et al. Cambrian Faults and Their Control on the Sedimentation and Reservoirs in the Ordos Basin, NW China[J]. Petroleum Exploration and Development, 2019, 46(05): 836-847.
[34] 魏柳斌, 包洪平, 严婷, 等. 鄂尔多斯盆地东部奥陶系马家沟组五段5亚段微生物碳酸盐岩发育特征及储集意义[J]. 石油学报, 2021, 42(08): 1015-1025 doi: 10.7623/syxb202108004
WEI Liubin, BAO Hongping, YAN Ting, et al. Development Characteristics and Significance of Microbial Carbonate Reservoirs in the Fifth Submember of Member 5 of Ordovician Majiagou Formation in the Eastern Ordos Basin[J]. Acta petrolei Sinica, 2021, 42(08): 1015-1025. doi: 10.7623/syxb202108004
[35] 吴浩, 张春林, 纪友亮, 等. 致密砂岩孔喉大小表征及对储层物性的控制——以鄂尔多斯盆地陇东地区延长组为例[J]. 石油学报, 2017, 38(08): 876-887
WU Hao, ZHANG Chunlin, JI Youliang, et al. Pore Throat Size Characterization of Tight Sandstone and its Control on Reservoir Physical Properties: A Case Study of Yanchang Formation, Eastern Gansu, Ordos Basin[J]. Acta petrolei Sinica, 2017, 38(08): 876-887.
[36] 徐兴雨. 鄂尔多斯盆地断裂构造及其控藏作用研究[D]. 东营: 中国石油大学(华东), 2020
XU Xingyu. Study on Faults Structure and Reservoir Control in Ordos Basin[D]. Dongying: China University of Petroleum (East China), 2020.
[37] 徐永昌. 天然气中氦同位素分布及构造环境[J]. 地学前缘(中国地质大学, 北京), 1997, 4(3/4): 185-190
XU Yongchang. Helium Isotope Distribution of Natural Gasses and its Structural Setting[J]. Earth Science Frontiers[J]. Earth Science Frontiers(China University of Geosciences, Beijing), 1997, 4(3/4): 185-190.
[38] 许文强, 袁炳强, 张春灌, 等. 鄂尔多斯盆地渭北隆起带重磁场特征[J]. 煤田地质与勘探, 2015, 43(06): 114-120 doi: 10.3969/j.issn.1001-1986.2015.06.024
XU Wenqiang, YUAN Bingqiang, ZHANG Chunguan, et al. Characteristics of Gravity and Magnetic Field in Weibei Uplift of Ordos basin [J]. Coal geological & Exploration, 2015, 43(06): 114-120. doi: 10.3969/j.issn.1001-1986.2015.06.024
[39] 杨华, 刘新社. 鄂尔多斯盆地古生界煤成气勘探进展[J]. 石油勘探与开发, 2014, 41(02): 129-137
YANG Hua, LIU Xinshe, Progress of Paleozoic Coal-Derived as Gxploration in Ordos Basin, West China[J]. Petroleum exploration and development, 2014, 41(02): 129-137.
[40] 张春灌, 袁炳强, 李玉宏, 等. 基于重磁资料的渭河盆地氦气资源分布规律[J]. 地球物理学进展, 2017, 32(01): 344-349
ZHANG Chunguan, YUANG Bingqiang, LI Yuhong, et al. Distribution of Helium Resources in Weihe Basin Based on Gravity and Magnetic data[J]. Progress in Geophysics, 2017, 32(01): 344-349.
[41] 张健, 张海华, 贺君玲, 等. 东北地区氦气成藏条件与资源前景分析[J]. 西北地质, 2023, 56(1): 117−128.
ZHANG Jian, ZHANG Haihua, HE Junling, et al. Analysis of Helium Accumulation Conditions and Resource Prospect in Northeast China[J]. Northwestern Geology, 2023, 56(1): 117−128.
[42] 张宇轩, 吕鹏瑞, 牛亚卓, 等. 全球氦气资源成藏背景、地质特征与产能格局初探[J]. 西北地质, 2022, 55(04): 11-32 doi: 10.19751/j.cnki.61-1149/p.2022.04.002
ZHANG Yuxuan, LÜ Pengrui, NIU Yazhuo, et al. Preliminary Study on the Geological Characteristics, Resource Potential and Production Capacity Pattern of Global Helium Resources[J]. Northwestern Geology, 2022, 55(4): 11-32. doi: 10.19751/j.cnki.61-1149/p.2022.04.002
[43] 赵安坤, 王东, 时志强, 等. 四川盆地及周缘地区氦气资源调查研究进展与未来工作方向[J]. 西北地质, 2022, 55(4): 74−84.
ZHAO Ankun, WANG Dong, SHI Zhiqiang, et al. Exploration Status and Helium Resource Potential of the Helium-bearing Natural Gas Field in Sichuan Basin and Its Surrounding Areas[J]. Northwestern Geology, 2022, 55(4): 74−84.
[44] 周俊林, 李玉宏, 魏建设, 等. 渭河盆地固市凹陷华州北地区氦气地质条件与富集模式[J]. 西北地质, 2022, 55(4): 33−44.
ZHOU Junlin, LI Yuhong, WEI Jianshe, et al. Geological Conditions and Enrichment Model of Helium in North Huazhou Area of Gushi Depression, Weihe Basin, China[J]. Northwestern Geology, 2022, 55(4): 33−44.
[45] 周正. 鄂尔多斯南缘构造特征研究[D]. 西安: 西北大学, 2009
ZHOU Zheng. Research on the Structural Characteristics of the Southern Region of Ordos [D]. Xi’an: Northwest University, 2009.
[46] 邹勇军, 肖富强, 章双龙, 等. 江西省温泉伴生气氦含量特征及其成因分析[J]. 西北地质, 2022, 55(4): 85-94
ZOU Yongjun, XIAO Fuqiang, ZHANG Shuanglong, et al. Characteristics and Causes of Helium Content in Hot Spring Associated Gas of Jiangxi Province[J]. Northwestern Geology, 2022, 55(4): 85-94.
[47] Feng Xuliang, Yuan Bingqiang, Li Yuhong, et al, Distribution of Helium Resources in Weihe Basin, Central China: Insight from 3D Magnetic Inversion[J]. Journal of Earth Science, 2022, 33(4): 977–992.
[48] WANG Xiaofeng, LIU Wenhui, LI Xiaobo, et al. Radiogenic Helium Concentration and Isotope Variations in Crustal Gas Pools from Sichuan Basin, China[J]. Applied Geochemistry, 2020, 117: 104586. doi: 10.1016/j.apgeochem.2020.104586
[49] WANG Wanyin, PAN Yu, QIU Zhiyun. A New Edge Recognition Technology Based on the Normalized Vertical Derivative of the Total Horizontal Derivative for Potential Field Data[J]. Applied Geophysics, 2009, 6(03): 226-233. doi: 10.1007/s11770-009-0026-x