摘要
本文用四种数学模型计算了洛川黄土剖面序列样品,发现九个与古地磁事件或地层分层对应的地球化学界线和四个稳定周期段:364—222ka,141—84ka,45—34ka和25—14ka。四个周期段与地球轨道要素和深海岩心δ^(18)O值的变化周期一致,表明第四纪气候变迁受天文因素控制。
In this paper variations in the contents of major chemical components and trace elements of sequential samples of loess and paleosol from the Luochuan section in Shaanxi Province have been studied. Nine geochemical boundaries respectively corresponding to paleomagmatic events or stratigraphic boundaries have been identified from among the strata of loess and poleosol. Also four main period-terms changing in element content, which are 364-222 ka, 141-84 ka, 45-34 ka and 25-14 ka, have been recognized. It is evident that the evolution of chemical ele-ments is of phase and periodicity. The four period-terms mentioned above are consistent with those calculated by Milankovitch for elements of Earth's orbits and oxygen isotopic (6 0) values for deep-sea drill cores. That is because paleoclimatic changes in the Quaternary period are controlled by some astronomical factors.
出处
《地球化学》
CAS
1987年第4期381-388,共8页
Geochimica
