摘要
以J.A.Clark为代表的全球海面变化均衡模式为基础,讨论冰盖形或对地核运动的影响。数值计算表明,由于地核偏离地心的运动,不同海区大约有±1.54m的海面波动。把这个结果叠加在均衡模式的结果之上,会使预测的结果与所观察结果更为符合。
Based on J. A. Clark's isostatic model of global sea level changes, this paper discusses the effect of formation of ice sheet in Arctic region on the movement of the Earth's core. Numerical calculation shows that the ocean surface in different regions may fluctuate about 1.54m due to eccentric movement of Earth's core. Summarizing this calculation result and the result of Clark's isostatic model, the predicted result is in good agreement with the previously observed data. After balancing the action of ice sheet in Antarctic region, we assume the partial melting of ice sheet in Arctic region V to be 25.7 Mkm^3, and its gravity is the same as a curved disc. By the calculation, we can see that when the solid core moved toward ice sheet 2.1 kin, the gravity of ice sheet can be balanced with the liquid core This movement of the solid core can raise (or lower) the sea-level 1.54 m in the Northern Hemisphere and lower (or raise) 1.54m in the Sou- thern Hemisphere. After postglacial isostatic adiustment, the exess masses of ice sheet will disappear. and the solid core will move back to the Earth's centre. The sea level will change in the same way. When this ice sheet melted, all the changes would be reverse. Thus this method is provided for calculating the changes in sea level which cocur when ice and water masses are redistributed on the surface of elastic and viscoelatic non-rotating Earth models after Farrell and Clark. Morner (1987) and Vestine (1957) have pointed out this movement of the core. In this paper, the calculation only provide the dynamic process for this movement.
出处
《地质科学》
CAS
CSCD
北大核心
1992年第4期406-408,共3页
Chinese Journal of Geology(Scientia Geologica Sinica)
关键词
海平面
均衡模式
冰盖
全球
Sea level, Isostafic model, Ice sheet
