华北寒武、奥陶系灰岩潮汐韵律与地月轨道参数的演化

Tidal Rhythmites in Cambrian-Ordovician, North China and Evolution of Orbit Parameters

通过对采自华北地区寒武、奥陶系灰岩样品进行磨光、涂漆等处理 ,在放大镜下读取小层厚度数据 ,进行傅立叶频谱分析 ,识别出相对应于日、双周、月的潮汐周期的记录 ,得到寒武、奥陶纪每个太阴月有 2 9.9,2 9.8d ;参考生物化石研究成果 ,对寒武、奥陶纪地月轨道参数进行计算 ,得到寒武、奥陶纪每年分别有 384 .5 ,381.7d ,每天分别有 2 2 .798,2 2 .96 3h ;寒武、奥陶纪地月距离分别为 5 8.76 ,5 8.96个地球半径及月球后退速率分别为 4 .2 5 ,4 .18cm/a等地月轨道参数 .研究结果表明从寒武纪到奥陶纪 ,具有地球旋转速度变慢、地月距离增大、月球后退速率减小等变化趋势 .

When the limestone of Cambrian-Ordovician from North China is polished and painted, the thickness of its little layers is read with the help of the magnifier. Then Fast Fourier transform and spectrum analysis is made and the tide period records in day, fortnight and month is identified from the laminae in the limestone. It was found that there were 29.9 d for a lunar month in Cambrian and in Ordovician 29.8 d; that there were 384.5 d for a year in Cambrian and in Ordovician 381.7 d and that there were 22.798 h for a day in Cambrian and in Ordovician 22.963 h. It has also been learned that Earth-Moon distances in Cambrian was 58.76 Earth's radius, in Ordovician 58.96 Earth's radius and that the lunar retreat rates in Cambrian was 4.25 cm·a -1 year and in Ordovician 4.18 cm·a -1. The result shows that the velocity of the Earth rotation had been slowed down from Cambrian to Ordovician, and that the Earth-Moon distance had been increasing while the rate of lunar retreat had been decreasing.