...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Geophysical Research. Biogeosciences >Predicted seafloor topography of the New Zealand region: A nonlinear least squares inversion of satellite altimetry data
【24h】

Predicted seafloor topography of the New Zealand region: A nonlinear least squares inversion of satellite altimetry data

机译：新西兰地区的预测海底地形：卫星测高数据的非线性最小二乘反演

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

We use a nonlinear least squares inversion to derive predicted seafloor topography (hereinafter referred to as RW99) for the New Zealand region (146 degrees E-165 degrees W, 60 degrees S-25 degrees S), combining altimetry data from ERS-1 and Geosat Geodetic Missions, as well as available shipborne gravity and echo sounding data. Currently, the lithospheric component of the model is principally applicable to thinly sedimented oceanic basins; however, we have attempted, though with only partial success, to compensate for regional crustal variations. The upper part of the oceanic lithosphere has an elastic behavior related to a half-space cooling model and flexing under seafloor relief load. Using least squares theory, the topographic solution is derived as a linear combination of altimetry and in situ measurements with adjusted coefficients. These coefficients are iteratively fitted using nonlinear operators between bathymetry and altimetry-derived gravity anomalies assuming their error distributions are Gaussian. The theory enables sparse in situ data to be included in the inversion, such as depth soundings and marine gravity profiles. In comparison with the global model of Smith and Sandwell [1997](hereinafter referred to as SS97); the RW99 predicted topography is constrained by over threefold more shipborne soundings data and the inclusion of shipborne gravity data. Three strategies are used to validate the RW99 model. Compared to the root-mean-square (rms) error of 310 m of the SS97 model, final residual differences for the RW99 model are within the range of 104-250 m. These component errors are the result of uncertainties of model parameters, especially the elastic thickness and the relief density, but also the complexity of seafloor topography. In addition, the model inversion does not presently consider gravitational contributions of marine sediments of Variable thickness. [References: 55]
机译：我们结合ERS-1和ERS-1的测高数据，使用非线性最小二乘反演得出新西兰地区（146度E-165度W，60度S-25度S）的预测海底地形（以下称为RW99）。 Geosat大地测量任务，以及可用的舰载重力和回声测深数据。目前，该模型的岩石圈成分主要适用于稀薄沉积的海盆。然而，尽管仅有部分成功，我们仍试图弥补地壳变化。海洋岩石圈的上部具有与半空间冷却模型有关的弹性行为，并在海底卸荷载荷作用下弯曲。使用最小二乘理论，地形解是通过调整系数的测高和原位测量的线性组合得出的。假设它们的误差分布为高斯分布，可以使用测深法和高度计引力异常之间的非线性算子对这些系数进行迭代拟合。该理论使稀疏的原位数据可以包含在反演中，例如深度测深和海洋重力剖面。与Smith和Sandwell [1997]的全球模型（以下简称SS97）相比; RW99预测的地形受到船载探测数据的三倍多和船载重力数据的约束。使用三种策略来验证RW99模型。与SS97模型的310 m的均方根（rms）误差相比，RW99模型的最终残差在104-250 m的范围内。这些分量误差是模型参数不确定性的结果，尤其是弹性厚度和浮雕密度，以及海底地形的复杂性。此外，模型反演目前未考虑可变厚度海洋沉积物的重力贡献。 [参考：55]

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号