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A study of the wide field electromagnetic method under extremely cold conditions |
ZHAN Shao-Quan( ), LI Ai-Yong, WANG Dao-Li, HAO Hong-Lei, WANG Lei |
No. 814 Geological Party, East China Bureau of Mineral Exploration and Development,Zhenjiang 212005, China |
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Abstract In order to extend the construction field of the wide field electromagnetic method and break through the restricted area of the wide field electromagnetic method application under extremely cold conditions, the authors studied the experimental technology of wide field electromagnetic method under extremely cold conditions. A comparative test was carried out between the exposed permafrost in spring and the extremely cold conditions and the exposed permafrost and the unexposed permafrost in the extremely cold conditions. The feasibility of construction under extremely cold conditions was explored. Various warm-keeping methods and measures to overcome the high resistance of frozen soil layers were applied in practice, and a set of exploration technological means under extremely cold conditions were summarized,which can be used to carry out the wide field electromagnetic method construction under extremely cold conditions so as to ensure the quality of data.
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Received: 21 April 2020
Published: 26 October 2020
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Location map of the test area
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地层层序 | 厚度/m | 标志性岩性 | 系 | 统 | 组 | 代号 | 第四系 | | | | 0~143 | 黏土与砂层、砂砾层,盆地北部有近代玄武岩喷发 | 新近系 | | 泰康组 | N2t | 0~165 | 上部灰黄-灰绿色泥岩和泥质粉砂岩,下部灰黄色砂砾层 | 大安组 | N1d | 0~123 | 上部灰色泥岩、页岩夹砂岩,下部砂砾层 | 古近系 | | 依安组 | E3y | 0~250 | 泥岩、砂质泥岩、粉砂岩,时夹薄层褐煤,底部砂砾岩 | 白垩系 | 上统 | 明水组 | K2m | 0~624 | 上段为泥岩、砂质泥岩与灰绿色砂岩互层;下段灰黑、灰色泥页岩,灰绿、灰色泥质粉砂岩、砂岩、砂砾岩 | 四方台组 | K2s | 0~413 | 棕红、灰绿色泥岩、砂质泥岩夹棕红色砂岩、砂砾岩 | 嫩江组 | K2n | 157~1237 | 共分五段,主要岩性为砂岩、粉砂岩与泥岩等 | 姚家组 | K2y | 60~230 | 共分为三段,主要岩性为泥岩、粉砂岩,盆地中部有灰黑色泥岩、薄层油页岩。盆地边缘为厚层砂砾岩 | 青山口组 | K2qn | 78~716 | 共分为三段,盆地中部、东南部为灰黑色泥岩夹薄层粉砂岩,底部夹油页岩。盆地边缘为厚砂层砂砾岩 | 下统 | 泉头组 | K1q | 0~2154 | 共分为四段,主要岩性为泥岩、泥质粉砂岩、粉砂岩等,第三段和第四段夹灰色、黑褐色含油粉砂岩 | 登娄库组 | K1d | 0~1739 | 分为四段,主要岩性为泥岩、细砂岩、砂岩,底部见砾岩 | 二叠系 | 上统 | 林西组 | P3l | | 灰黑色砂泥质板岩、板岩,黑色板状千枚岩、变余粉砂岩、变质粉砂岩 | 中统 | 哲斯组 | P2z | | 黑色泥板岩、变余砂砾岩、泥灰岩、石灰岩夹强碳酸盐化流纹岩互层及夹有安山岩 | 下统 | 大石寨组 | P1d | | 上部以中性熔岩及凝灰岩为主,夹泥板岩、凝灰质砂岩等;下部以中酸性熔岩及凝灰岩为主 | 寿山沟组 | P1ss | | 粉砂岩、凝灰质砂岩、千枚岩 | 石炭系 | 上统 | 阿木山组 | C2a | | 一套海相碳酸盐岩及碎屑岩地层,中部和下部夹有少量砂岩、粉砂岩及泥岩 | 本巴图组 | C2b | | 以砂岩为主夹灰岩及火山岩组合 | | 色日巴彦 敖包组 | D3-C1 | | 下部为紫灰色中细粒杂砂岩与钙质粉砂岩互层;上部为黄褐-紫灰色中细粒钙质长石石英砂岩与粉砂岩互层 | 前古生界 | | | AnPz | | 花岗片麻岩、片麻状花岗岩、片岩类等 |
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Main strata table in the test area
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地层 | 岩性 | 电阻率/(Ω·m) | K1q-Q | 泥岩、砂岩、粉砂岩局部夹砾岩 | 30 | P2-P3 | 板岩、千枚岩、变余砂岩等 | 15 | AnC+γ | 片岩、片麻岩及岩体 | 220 | K1h-K1d | 泥岩、粉砂岩夹油页岩 | 15 | C-P1 | | 45 |
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Resistivity statistical results of borehole logging in working area
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Comprehensive geological section based on 2D resistivity inversion of the test section
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类别 | 发射接地电阻 | 发射电流 | 接收接地电阻 | 高频叠加次数 | 低频叠加次数 | 采集时间 | 极寒条件未揭穿冻土层 | 15 Ω | 80 A | 1.5~20 kΩ | 30次以上 | 6次以上 | 2 h | 春季 | 8.9 Ω | 80 A | 200~900 Ω | 30次以上 | 6次以上 | 2 h |
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Comparison of construction parameters of unexposed permafrost under spring and extreme cold conditions
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Comparison of frequency-resistivity curves of unexposed permafrost under spring and extreme cold conditions
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Unexposed (a) and exposed permafrost (b)
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类别 | 发射接地电阻 | 发射电流 | 接收接地电阻 | 高频叠加次数 | 低频叠加次数 | 采集时间 | 极寒条件未揭穿冻土层 | 15 Ω | 80 A | 1.5~20 kΩ | 30次以上 | 6次以上 | 2 h | 极寒条件揭穿冻土层 | 7.1 Ω | 80 A | 1.5~20 kΩ | 30次以上 | 6次以上 | 2 h |
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Collection parameters of exposed and unexposed permafrost under extremely cold conditions
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Comparison of frequency-resistivity curves between unexposed and exposed permafrost under extremely cold conditions
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[1] |
何继善. 大深度高精度广域电磁勘探理论与技术[J]. 中国有色金属学报, 2019,29(9):1809-1816.
|
[1] |
He J S. Theory and technology of wide field electromagnetic method[J]. The Chinese Journal of Nonferrous Metals, 2019,29(9):1809-1816.
|
[2] |
胡涂, 李帝铨. E-Ex广域电磁法对低阻薄层分辨能力探讨[J]. 物探化探计算技术, 2014,36(3):297-303.
|
[2] |
Hu T, Li D Q. Distinguish ability on thin resistant layered structure of E-Ex mode of wide field electromagnetic sounding method[J]. Computing Techniques for Geophysical and Geochemical Exploration, 2014,36(3):297-303.
|
[3] |
郑冰, 李帝铨. 广域电磁法和大地电磁法在中国南方某页岩区块的对比实验[J]. 油气地球物理, 2015,13(3):45-49.
|
[3] |
Zheng B, Li D Q. Comparative test of wide field electromagnetic method and MT at a shale gas block in the south of China[J]. Petroleum Geophysics, 2015,13(3):45-49.
|
[4] |
赵福海, 王导丽, 张明鹏, 等. 松辽盆地北部石炭-二叠系底埋深综合物探预测技术[J]. 矿产与地质, 2018,32(1):116-121.
|
[4] |
Zhao F H, Wang D L, Zhang M P, et al. The comprehensive geophysical prediction technique of the bottom buried depth of Carboniferous-Permian in the northern Songliao Basin[J]. Mineral Resources and Geology, 2018,32(1):116-121.
|
[5] |
何继善. 广域电磁法和伪随机信号电法[M]. 北京: 高等教育出版社, 2010.
|
[5] |
He J S. Wide field electromagnetic sounding methods and pseudo-random signal coding electrical method[M]. Beijing: Higher Education Press, 2010.
|
[6] |
何继善. 广域电磁测深法研究[J]. 中南大学学报:自然科学版, 2010,41(3):1065-1072.
|
[6] |
He J S. Wide field electromagnetic sounding methods[J]. Journal of Central South University: Science and Technology, 2010,41(3):1065-1072.
|
[7] |
吴旭. 探析广域电磁法在隐伏矿产资源勘查中的应用[J]. 世界有色金属, 2018,(6):147-149.
|
[7] |
Wu X. Application of wide area electromagnetic method in concealed exploration of mineral resources[J]. World Nonferrous Metals, 2018, (6):147-149.
|
[8] |
刘益中, 詹少全, 李爱勇, 等. AMT在印尼某铁矿区勘查中的应用[J]. 物探与化探, 2012,36(4):559-561.
|
[8] |
Liu Y Z, Zhan S Q, Li A Y, et al. The Application Of Amt Method To The Exploration Of An Iron Ore District In Indonesia[J]. Geophysical and Geochemical Exploration, 2012,36(4) : 559-561.
|
[9] |
詹少全, 陈中, 李爱勇, 等. 重磁电综合解释在突泉盆地油气勘查中的应用[J]. 矿产与地质, 2017,30(1):131-137,142.
|
[9] |
Zhan S Q, Chen Z, Li A Y, et al. Application of combined gravity-magnetic-electrical explanation method in Tuquan Basin oil and gas exploration[J]. Mineral Resources and Geology, 2017,30(1):131-137,142.
|
[10] |
李金铭. 地电场与电法勘探[M]. 北京: 地质出版社, 2005.
|
[10] |
Li J M. Geoelectric field and electrical exploration [M]. Beijing: Geological Publishing House, 2005.
|
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