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王硕儒 《中国海洋大学学报(自然科学版)》1984,(4)
位场变换是地磁(重力)场数据处理系统的重要组成部分。根据位场变换结果可以从实测地磁(重力)场的数据中提取大量有用信息,因而它的应用大大丰富了重、磁异常的解释方法,从而提高重、磁异常解释成果的可靠程度,而位场分量之间的相互换算又是位场变换中的一个重要问题。尤其是对于直孔的井中磁测,由于△H至今仍无法实 相似文献
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针对海洋区域离岸距离5~30km的范围内船载重力测量数据覆盖空白的现状,基于已有测线数据,对其进行不同空间距离采样形成对应的采样序列。利用动态时间规整算法计算其与初始测线数据的相关系数,依据相关系数与采样距离之间的关系,确定了最优重采样空间距离新方法。以最优重采样空间距离对测线数据进行重采样,利用拉格朗日插值算法,沿测线方向将测线数据向陆地推估。经过不同测线的内外部检核,结果表明船载重力测量向陆地方向扩展的保守距离约为5~10km,减少了船载重力测量数据在近岸海域覆盖空白的面积。本研究成果可为建立陆海一致垂直基准工作提供更全面的基础数据,技术方法可为航空重力、地磁等测线数据的精细处理及应用提供参考。 相似文献
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海水层对地磁日变的影响 总被引:1,自引:0,他引:1
在海洋地磁测量中地磁日变的影响不可忽视,由于海底地磁日变观测站可建在测区内或附近,通常情况下能较好地反映测区范围内的地磁日变状况.但从实际观测资料对比发现,海底地磁观测站站位水深对地磁有效信息的保留存在一定的相关性.随着水深增大,其保留的信息量逐渐减少,即水层对地磁信息有着明显的衰减作用. 相似文献
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提出地磁日变改正中需要顾及地磁长期变化和磁扰的可靠分离,保证磁力数据改正处理具有明确的基准,提高拼接整合的精度.如果日变站能够控制测区,两者可采用时间同步固定的地磁正常场作为磁异常基准,测区的地磁长期变化由日变站实测的地磁长期变化来改正,反之,对日变站和测区应分别采用时间同步变化的地磁正常场作为磁异常基准,测区的地磁长期变化由地磁正常场的地磁长期变化来改正.为此,应该明确定义与时间相关的日变改正基值为地磁正常场与地磁异常之和.通过磁静日总场观测值偏离正常场的某种形式的长期平均值,可以逼近日变站的地磁异常.磁扰的分离应保证磁扰初动和消失相对于磁静日无磁扰的连续过渡.采用综合模型一并进行日变改正、正常场及其长期变化改正,可以更好地解决目前日变改正中遇到的问题. 相似文献
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地磁日变改正是海洋磁测资料处理过程中的一个重要环节。本文利用地磁场综合模型与IGRF模型联合计算了西太平洋某调查工区的地磁日变数据,对比分析了相同位置的海洋地磁日变站观测数据。使用两种不同类型的地磁日变数据,分别对该测区中15条测线进行了磁测数据处理,并对这些测线及其56个交叉点进行了误差分析。研究结果认为:①当用计算数据做海洋磁测的处理时,其交叉点内符合精度在调差前基本满足海洋地质规范的要求,在调差后完全符合海洋地质规范的要求,但使用计算数据的精度低于实测数据。②磁静时,计算日变曲线和实测日变曲线拟合程度高;磁扰时,两者幅值差异较大,磁扰越强相关系数越小。磁情指数K4时的模型计算数据,建议谨慎使用或不使用。 相似文献
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王硕儒 《山东海洋学院学报》1984,14(4):87-93
位场变换是地磁(重力)场数据处理系统的重要组成部分。根据位场变换结果可以从实测地磁(重力)场的数据中提取大量有用信息,因而它的应用大大丰富了重、磁异常的解释方法,从而提高重、磁异常解释成果的可靠程度,而位场分量之间的相互换算又是位场变换中的一个重要问题。 相似文献
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东海莫霍面起伏与地壳减薄特征初步分析 总被引:3,自引:0,他引:3
收集、整理大量由地震剖面提供的沉积层厚度资料,得到东海沉积层等厚图。对完全布格重力异常进行沉积层重力效应改正后,得到剩余重力异常,利用地震资料揭示的莫霍面深度值来约束界面反演得到东海莫霍面埋深。结果表明,东海陆架盆地莫霍面深度在25~28 km之间平缓变化,地壳厚度为14~26 km,西厚东薄;冲绳海槽盆地莫霍面深度为16~26 km,地壳厚度为12~22 km,北厚南薄。东海陆架盆地东部与冲绳海槽盆地南部地壳减薄明显,拉张因子分别达到2.6和3。初步分析认为冲绳海槽地壳以过渡壳为主,并未形成洋壳。 相似文献
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小波分析与解析延拓方法相结合研究东海深部构造 总被引:3,自引:0,他引:3
东海是环太平洋活动构造带的重要组成部分,是探讨西太平洋边缘及边缘海形成演化的重要窗口。向上延拓主要用来削弱局部异常,突出深部异常,小波分析是重磁场位场分解的有效工具,不仅能提取深部异常,还能更好地将区域异常和局部异常分离。本文利用东海及邻域最新的布格重力异常数据资料,将小波分析与解析延拓方法相结合,分析对比向上延拓20 km的布格重力异常结果与小波分析4阶逼近布格重力异常结果,结合东海及邻域莫霍面的深度,对重力场及莫霍面深度进行初步研究。其中小波4阶逼近结果代表莫霍面形态,小波4阶细节结果代表东海及邻域凹陷凸起形态。 相似文献
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论现实主义原则在海洋地质学中的应用——以中国海岸带及近海大陆架为例 总被引:6,自引:2,他引:6
近年来,在海洋地质学和沉积学中广泛应用模式概念,试图建立模式以说明或解释某些海洋地质学现象.建立模式的理论根据是经典地质学的一条著名原则,即“现在是过去的钥匙”,这就是一致论或现实主义原则.最近十多年来,研究古代沉积岩的论文绝大多数都有现代或全新世类比(analogue)一节,即主要根据与现代现象的类比,来解释古代沉积岩的发生和成因.这种类比促进了近年海洋地质学和沉积学的巨大发展.但简单的类比往往存在若干缺点和问题,甚至导致错误的结论. 相似文献
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Sea gravity measurements were carried out over the East China Sea and its neighbourhood using a ZYZY-type Sea Gravimeter in 1977 and 1979.Maps of the free air gravity anomaly, the Bouguer gravity anomaly, crustal thickness and synthetic gravity across the Ryukyu trench have been compiled. The gravity anomaly distribution and the characteristics of the crustal structure are discussed. 相似文献
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The macroalgal blooms of floating brown algae Sargassum horneri are increasing in the Yellow Sea and East China Sea during the past few years. However, the annual pattern of Sargassum bloom is not well characterized. To study the developing pattern and explore the impacts from hydro-meteorologic environment, high resolution satellite imageries were used to monitor the distribution, coverage and drifting of the pelagic Sargassum rafts in the Yellow Sea and East China Sea from September 2019 to Au... 相似文献
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Xin’gang Luo Wanyin Wang Ying Chen Zhizhao Bai Dingding Wang Tao He Yimi Zhang Ruiyun Ma 《海洋学报(英文版)》2023,42(3):227-242
As one of the main controlling factors of oil and gas accumulation, faults are closely related to the distribution of oil and gas reservoirs. Studying how faults control petroliferous basins is particularly important. In this work, we investigated the plane positions of major faults in the China seas and its adjacent areas using the normalized vertical derivative of the total horizontal derivative (NVDR-THDR) of the Bouguer gravity anomaly, the fusion results of gravity and magnetic anomalies, and the residual Bouguer gravity anomaly. The apparent depths of major faults in the China seas and its adjacent areas were inverted using the Tilt-Euler method based on the Bouguer gravity anomaly. The results show that the strikes of the faults in the China seas and its adjacent areas are mainly NE and NW, followed by EW, and near-SN. Among them, the lengths of most ultra-crustal faults are in the range of 1 000–3 000 km, and their apparent depths lie between 10 km and 40 km. The lengths of crustal faults lie between 300 km and 1 000 km, and their apparent depths are between 0 km and 20 km. According to the plane positions and apparent depths of the faults, we put forward the concept of fault influence factor for the first time. Based on this factor, the key areas for oil and gas exploration were found as follows: the east of South North China Basin in the intracontinental rift basins; the southeast region of East China Sea Shelf Basin, the Taixinan and Qiongdongnan basins in the continental margin rift basins; Zhongjiannan Basin in the strike-slip pull-apart basins; the Liyue, Beikang, and the Nanweixi basins in the rifted continental basins. This work provides valuable insights into oil and gas exploration, mineral resource exploration, and deep geological structure research in the China seas and its adjacent areas. 相似文献
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This paper presents actuality of investigation and study of the crustal structure characters of East China Sea at home and abroad. Based on lots of investigation and study achievements and the difference of the crustal velocity structure from west to east, the East China Sea is divided into three parts - East China Sea shelf zone, Okinawa Trough zone and Ryukyu arc-trench zone. The East China Sea shelf zone mostly has three velocity layers, i.e., the sediment blanket layer (the velocity is 5.8-5.9 km/s), the basement layer (the velocity is 6.0-6.3 km/s), and the lower crustal layer (the velocity is 6.8-7.6 km/s). So the East China Sea shelf zone belongs to the typical continental crust. The Okinawa Trough zone is located at the transitional belt between the continental crust and the oceanic crust. It still has the structural characters of the continental crust, and no formation of the oceanic crust, but the crust of the central trough has become to thinning down. The Ryukyu arc-trench zone belongs to the transitional type crust as a whole, but the ocean side of the trench already belongs to the oceanic crust. And the northwest Philippine Basin to the east of the Ryukyu Trench absolutely belongs to the typical oceanic crust. 相似文献
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本文作者所在单位1988年在舟东共测得地磁剖面67条,剖面总长度为2978km。根据测网中306个测线交点上交点差的方均根值,确定精度为3nT,这次测量是东海陆架区油气勘探调查的一部分。 相似文献