舰船、潜艇等水中目标会产生磁异常场，这一物理场中包含丰富的目标固有信息。航空磁测是一种快速高效的磁测方式，通过一定的向下延拓算法，能够准确识别定位目标。但现有的磁异常向下延拓方法延拓深度有限，不能从航磁数据向下延拓至海面。BP神经网络方法具有较强的非线性映射能力，在函数逼近和模式识别等领域具有广泛的应用。本文以BP神经网络方法为基础，建立一种磁异常数据向下延拓方法，经理论模型验证，本方法准确可靠，能够较稳定地进行30倍点距的向下延拓，达到从航磁数据延拓至海面的目的。
Underwater targets such as ships and submarines will generate magnetic anomalous fields, which contain rich target inherent information. Aerial magnetic survey is a fast and efficient magnetic survey method, which can accurately identify and locate the target through a certain downward extension algorithm. However, the existing downward extension methods of magnetic anomalies have limited extension depth and cannot extend downward from aeromagnetic data to the sea surface. The BP neural network method has strong nonlinear mapping ability, and has a wide range of applications in the fields of function approximation and pattern recognition. Based on the BP neural network method, this paper establishes a downward continuation method of magnetic anomaly data. The theoretical model has verified that this method is accurate and reliable, and can stably carry out downward continuation of 30 times the point distance, so as to achieve the goal of continualnavigation. The purpose of extending magnetic data to the sea surface.
2023,45(18): 133-138 收稿日期：2022-07-15
DOI：10.3404/j.issn.1672-7649.2023.18.023
分类号：U674.7
作者简介：钟炀(1995-),男,硕士研究生,研究方向为水下磁场、特低频电磁场
参考文献：
[1] 董鹏, 孙哲, 邹念洋, 等. 国外磁探潜装备现状及发展趋势[J]. 舰船科学技术, 2018, 40(21): 166–169.
DONG P, SUN Z, ZOU N Y, et al. The situation and development trend of foreign magnetic exploration submarine equipment[J]. Ship Science and Technology, 2018, 40(21): 166–169.
[2] 王光辉, 朱海, 郭正东, 等. 舰船感应磁性的磁异常信号特征[J]. 舰船科学技术, 2015, 37(9): 137–139
WANG Guang-hui, ZHU Hai, GUO Zheng-dong, et al. MAD signal character of ship's induced magnetism[J]. Ship Science and Technology, 2015, 37(9): 137–139
[3] 管志宁. 地磁场与磁力勘探[M]. 北京: 地质出版社, 2005: 85–100.
[4] 焦新华, 吴燕冈. 重力与磁力勘探[M]. 北京: 地质出版社, 2009: 190–195.
[5] 于德武, 龚胜平. 对迭代法位场向下延拓方法的剖析[J]. 吉林大学学报(地球科学版), 2015, 45(3): 934–940.
YU D W, GONG S P. Analysis of the potential field downward continuation iteration method[J]. Journal of Jilin University(Earth Science Edition), 2015, 45(3): 934-940.
[6] 尹伟言, 陈真, 蒋涛, 等. 地面重力数据向上延拓方法比较[J]. 地理空间信息, 2018, 16(7): 75–76+95+10
YIN W Y, CHEN Z, JIANG T, et al. Comparison of upward continuation methods for ground gravity data[J]. Geospatial Information, 2018, 16(7): 75–76+95+10
[7] 周智文, 何水原, 孟小红, 等. 约束等效源稳定向下延拓方法研究[J]. 地球物理学报, 2022, 65(2): 754–762.
ZHOU Z W, HE S Y MENG X H, et al. Stable downward continuation of potential field data using an equivalent sourse method and a constrained strategy[J]. Chinese Journal of Geophysics, 2022, 65(2): 754–762.
[8] 赵亚博, 刘天佑. 迭代Tikhonov正则化位场向下延拓方法及其在尕林格铁矿的应用[J]. 物探与化探, 2015, 39(4): 743–748
ZHAO Y B, LIU T Y. The iterative Tikhonov regularization method for downward continuation of potential fields and its application to the Galinge iron deposit[J]. Geophysical and Geochemical Exploration, 2015, 39(4): 743–748
[9] EVJEN H M. The place of the vertical gradient in gravitational interpretations[J]. Geophysics, 2002, 1(1): 127–136
[10] PETERS L J. The direct approach to magnetic interpretation and its practical application[J]. Geophysics, 1949, 14(3): 290–320
[11] DEAN W C. Frequency analysis for gravity and magnetic interpretaion[J]. Geophysics, 2002, 23(1): 97–127
[12] FEDI M, FLORIO G. A stable downward continuation by using the ISVD method[J]. Geophysical Journal International, 2002, 151(1): 146–156
[13] 徐世浙. 位场延拓的积分-迭代法[J]. 地球物理学报, 2006(4): 1176–1182
XU S Z. The integral-iteration method for continuation of potential fields[J]. Chinese Journal of Geophysics, 2006(4): 1176–1182
[14] 徐世浙. 迭代法与FFT法位场向下延拓效果的比较[J]. 地球物理学报, 2007(1): 285–289
XU S Z. A comparison of effects between the iteration method and FFT for downward continuation of potential fields[J]. Chinese Journal of Geophysics, 2007(1): 285–289
[15] 刘东甲, 洪天求, 贾志海, 等. 位场向下延拓的波数域迭代法及其收敛性[J]. 地球物理学报, 2009, 52(6): 1599–1605
[16] 于波, 翟国君, 刘雁春, 等. 噪声对磁场向下延拓迭代法的计算误差影响分析[J]. 地球物理学报, 2009, 52(8): 2182–2188
[17] 曾小牛, 李夕海, 韩绍卿, 等. 位场向下延拓三种迭代方法之比较[J]. 地球物理学进展, 2011, 26(3): 908–915
ZENG X N, LI X H, HAN S Q, et al. A comparison of three iteration methords for downward continuation of potential fields[J]. Progress in Geophysics, 2011, 26(3): 908–915
[18] 钟炀, 管彦武, 石甲强, 等. 长方体全张量磁梯度的两种正演公式对比[J]. 世界地质, 2019, 38(4): 1073–1081+1090
[19] 骆遥, 姚长利. 长方体磁场及其梯度无解析奇点表达式理论研究[J]. 石油地球物理勘探, 2007, 42(6): 714–719
LUO Y, YAO C L. Theoretical study on cuboid magnetic field and gradient expression without singular point[J]. Oil Geophysical Prospecting, 2007, 42(6): 714–719
