Deconvolution of long-core paleomagnetic data of Ocean Drilling Program by Akaike's Bayesian Information Criterion minimization
Deconvolution of long-core paleomagnetic data of Ocean Drilling Program by Akaike's Bayesian Information Criterion minimization
复制标题
赤池贝叶斯信息准则最小化对大洋钻探计划长核古地磁数据的反褶积
DOI：
10.1029/95jb02811
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发表时间：
1996
影响因子：
--
通讯作者：
H. Shibuya
中科院分区：
文献类型：
--
作者：
H. Oda;H. Shibuya
基于贝叶斯统计，对海洋钻探项目（ODP）的长核古地磁资料进行了反褶积处理。深海沉积物样品是通过先进的活塞盖钻探获得的，由ODP的研究船（Joides Resolution）上的低温磁力计进行穿透测量，该船提供连续的古地磁记录。为了获得比拾取线圈的空间分辨率（约11厘米）所允许的更详细的磁化变化，开发了磁力计输出的反卷积。将磁化矢量建模为二阶差分L2范数参数化的平滑变化序列，然后采用矩阵计算作为平滑约束最小二乘法进行反卷积。通过最小化Akaike的贝叶斯信息准则来获得最佳平滑度，该准则是似然的对数度量。将该反卷积方案应用于人工合成反转记录卷积并加入高斯噪声产生的透传数据。对噪声的幅值进行估计，得到了小于传感器空间分辨率的变化量。反褶积也应用于769A和769B孔以5mm间隔测量的真实通穿数据。反褶积显示了磁化强度的变化，最大空间分辨率约为2cm。反褶积后的磁化强度与每隔5或10厘米在立方体样品上单独测量的磁化强度值很好地一致。
Deconvolution of long-core paleomagnetic data of the Ocean Drilling Program (ODP) was developed based on Bayesian statistics. Samples of deep-sea sediments obtained by drilling with an advanced piston corer are subjected to pass-through measurements by a cryogenic magnetometer aboard the ODP's research vessel (Joides Resolution) which provide continuous paleomagnetic records. Deconvolution of the magnetometer output was developed in order to obtain more detailed variations of the magnetization than permitted by the spatial resolution of the pickup coil (approximately 11 cm). The magnetization vector was modeled as a smoothly changing sequence parametrized by L2 norm of second-order difference and then deconvolved using a matrix calculation as a smoothness constrained least squares method. The optimum smoothness was obtained by minimizing Akaike's Bayesian Information Criterion which is a measure of the logarithm of the likelihood. This deconvolution scheme was applied to pass-through data artificially produced by convolving synthetic reversal record and adding a Gaussian noise. The amplitude of the noise was estimated and the variations shorter than the spatial resolution of the sensor were obtained. The deconvolution also was applied to the real pass-through data from Holes 769A and 769B measured at intervals of 5 mm. The deconvolution revealed variations of the magnetizations with a maximum spatial resolution of about 2 cm. The magnetizations after deconvolution were in good agreement with magnetization values measured separately on cube samples taken at intervals of 5 or 10 cm.