利用Matlab函数识别沉积物中的米兰柯维奇旋回信号  

Recognition of Milankovitch Cycles in Sediments by Using Matlab Functions

作　　者：赵庆乐[1] 张世红[1] 王婷婷[1] 吴怀春[1] 李海燕[1] 张元厚[2] 

机构地区：[1]中国地质大学地质过程与矿产资源国家重点实验室,北京100083 [2]吉林大学地球科学学院,长春130061

出　　处：《吉林大学学报（地球科学版）》2010年第5期1217-1220,共4页Journal of Jilin University：Earth Science Edition

基　　金：国家自然科学基金项目(40572019;40621002);中石化前瞻性研究项目(G0800-06-ZS-319)

摘　　要：针对旋回分析中需要对数据进行的各种处理,利用Matlab中集成的滤波(filter)函数、插值(interp1)函数、求均值(mean)函数、去线性趋势(detrend)函数、求方差(variance)函数及谱分析(pwelch)函数等的组合,编制了识别沉积物中米兰柯维奇旋回信号的程序。选择窗口宽度(window)约等于有用信号中最低频率信号的波长、交叠点数(noverlap)为窗口宽度的50%、傅里叶变换的数据点数(nfft)大于全部采样数据的长度且为2的最小整数次幂时,可获得较好的谱估计结果。其不足之处是不能估计背景的红噪声谱及给出谱峰值的置信水平。As an important and new dating method,cyclostratigraphy is extensively used on analyzing data of deep sea core and terrestrial well logs.According to the procedure of data processing during cyclostratigraphic analysis,we write a program to recognize Milankovitch cycles in sediments by combining Matlab functions such as filter,interp1,mean,detrend,variance and pwelch.When used to estimate the power spectra of time series,a better estimation result could be gotten if the parameter settings satisfy certain conditions.These conditions are parameter window should be about equal to the wavelength of the lowest frequency signal among useful signals,parameter noverlap be equal to 50% of the window length and parameter nfft be equal to the smallest power of two and must be great than the whole length of time series.The program can not be used to estimate the background red noise spectra as well as to estimate the confidence level of spectra peaks should be the shortcomings of the program.

关 键 词：旋回地层学 米兰柯维奇旋回 谱估计 MATLAB 

分 类 号：P53[天文地球—古生物学与地层学]