Gravity inversion of basement relief constrained by the knowledge of depth at isolated points

被引:46
|
作者
Leao, JWD [1 ]
Menezes, PTL [1 ]
Beltrao, JF [1 ]
Silva, JBC [1 ]
机构
[1] OBSERV NACL R GEN BRUCE, DEPT GEOFIS, BR-20921030 RIO DE JANEIRO, BRAZIL
关键词
D O I
10.1190/1.1444088
中图分类号
P3 [地球物理学]; P59 [地球化学];
学科分类号
0708 ; 070902 ;
摘要
We present an interpretation method for the gravity anomaly of an arbitrary interface separating two homogeneous media. It consists essentially of a downward continuation of the observed anomaly and the division of the continued anomaly by a scale factor involving the density contrast between the media. The knowledge of the interface depth at isolated points is used to estimate the depth d(1) of the shallowest point of the interface, the density contrast Delta rho between the two media, and the coefficients c(1) and c(2) of a first-order polynomial representing a linear trend to be removed from data. The solutions are stabilized by introducing a damping parameter in the computation of the downward-continued anomaly by the equivalent layer method. Different from other interface mapping methods using gravity data, the proposed method: (1) takes into account the presence of an undesirable linear trend in data; (2) requires just intervals for both Delta rho (rather than the knowledge of its true value) and coefficients c(1) and c(2); and (3) does not require the knowledge of the average interface depth z(o). As a result of (3), the proposed method does not call for extensive knowledge of the interface depth to obtain a statistically significant estimate of z(o); rather, it is able to use the knowledge of the interface depth nt just a few isolated points to estimate d(1), Delta rho, c(1), and c(2). Tests using synthetic data confirm that the method produces good and stable estimates as far as the established premises (smooth interface separating two homogeneous media and, at most, the presence of an unremoved linear trend in data) are not violated. If the density contrast is not uniform, the method may still be applied using Litinsky's concept of effective density. The method was applied to gravity data from Reconcavo Basin, Brazil, producing good correlations of estimated lows and terraces in the basement with corresponding known geological features.
引用
收藏
页码:1702 / 1714
页数:13
相关论文
共 50 条
  • [31] Depth model building by constrained magnetotelluric inversion
    Dell'Aversana, P
    Morandi, S
    [J]. ANNALS OF GEOPHYSICS, 2002, 45 (02) : 247 - 257
  • [32] Structural interpretation of Southern Main Ethiopian Rift basin using constrained full tensor gravity inversion of the basement morphology
    Kebede, Bisrat
    Mammo, Tilahun
    Misgie, Abebe
    [J]. HELIYON, 2022, 8 (05)
  • [33] An Improved Method for High-Precision Delineation of the Basement Relief Base on Gravity Inversion Using Multiconstraints From Borehole Data
    Liu, Yandong
    Wang, Jun
    Li, Fang
    Wang, Linfei
    Meng, Xiaohong
    [J]. IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, 2024, 62 : 1 - 10
  • [34] Simultaneous 3D depth-to-basement and density-contrast estimates using gravity data and depth control at few points
    Martins, Cristiano M.
    Barbosa, Valeria C. F.
    Silva, Joao B. C.
    [J]. GEOPHYSICS, 2010, 75 (03) : I21 - I28
  • [35] Multiscale nonlinear inversion of gravity data for depth-to-basement estimation via coupled stochastic-deterministic optimization
    Jamasb, Ali
    Motavalli-Anbaran, Seyed-Hani
    Entezar-Saadat, Vahid
    Zeyen, Hermann
    [J]. GEOPHYSICS, 2021, 86 (06) : G99 - G112
  • [36] Basement and cover architecture in the Central Pyrenees constrained by gravity data
    P. Clariana
    R. Soto
    C. Ayala
    A. M. Casas-Sainz
    T. Román-Berdiel
    B. Oliva-Urcia
    E. L. Pueyo
    E. Beamud
    C. Rey-Moral
    F. Rubio
    A. Margalef
    S. Schamuells
    N. Bach
    J. Martí
    [J]. International Journal of Earth Sciences, 2022, 111 : 641 - 658
  • [37] Basement and cover architecture in the Central Pyrenees constrained by gravity data
    Clariana, P.
    Soto, R.
    Ayala, C.
    Casas-Sainz, A. M.
    Roman-Berdiel, T.
    Oliva-Urcia, B.
    Pueyo, E. L.
    Beamud, E.
    Rey-Moral, C.
    Rubio, F.
    Margalef, A.
    Schamuells, S.
    Bach, N.
    Marti, J.
    [J]. INTERNATIONAL JOURNAL OF EARTH SCIENCES, 2022, 111 (02) : 641 - 658
  • [38] Three-dimensional constrained gravity inversion of Moho depth and crustal structural characteristics at Mozambique continental margin
    Yang, Shihao
    Wu, Zhaocai
    Fang, Yinxia
    Xu, Mingju
    Zhang, Jialing
    Yang, Fanlin
    [J]. ACTA OCEANOLOGICA SINICA, 2024, 43 (02) : 120 - 129
  • [39] An integrated method for gravity gradient inversion and gravity gradient depth imaging
    Tian, Yu
    Liu, Jinzhao
    Ye, Qing
    Shi, Lei
    Wang, Yong
    Ebbing, Joerg
    [J]. GEOPHYSICAL JOURNAL INTERNATIONAL, 2024, 238 (01) : 590 - 615
  • [40] Three-dimensional constrained gravity inversion of Moho depth and crustal structural characteristics at Mozambique continental margin
    Shihao Yang
    Zhaocai Wu
    Yinxia Fang
    Mingju Xu
    Jialing Zhang
    Fanlin Yang
    [J]. Acta Oceanologica Sinica, 2024, 43 (02) : 120 - 129