乔治王岛菲尔德斯半岛的地温特征和岩石热物理性质

1985—1986年度和1986—1987年度在菲尔德斯半岛对地面温度进行了测量,共获得129个数据,并对带回的样品进行了岩石热导率测量,共获得210个数据。本文在分析和归纳这些数据的基础上对菲尔德斯半岛的地温特征和岩石热物理性质进行了初步探讨。

CHARACTERISTICS OF GEOTEMPERATURE AND THERMOPHYSICAL PROPERTIES OF ROCKS ON THE FILDES PENINSULA

During 1985-1986 and 1986-1987 expeditions on Fildes Peninsula the ground temperature in 119 spots was measured. Then thermal conductivity measurements were made on the rock samples collected. 219 data have been obtained in total. After careful analysis some pre- liminary results can be summarized as follows:1.Most prat of Fildes Peninsula is an ice- and snowmolten land area during Antarctic summer. The localities with ground temperature below 0℃ are scattered around. The predominant ground temperature ranges from 0℃ to 2℃.2.The localities with elevating temperatures between 2 and 4℃ are distributed near fault zones and in dyke swarmp zones, wich usually are concentrated in the paleovolcanic centers and near the intrusive bodies.3.The localities with the highest in the peninsula ground temperature above 4℃ are totally coincident with the area of youngest (Eocene and Oligocene) volcanic breccia and lava of crateric phase where hydrothermal veins are widespreadly developed.4.The average annual ground temperature in the southern part of Fildes Peninsula as on the continents is lower than the average annual air temperature. This may be attributable to the cooling effect due to the, thick permanent ice sheet covering the Antarctic Land.5.The Tertiary volcanic rocks widely spread over the peninsula belong to rocks of medium thermal conductivity with a mean value of 1.69-1.78 W / mK.6.The average thermal conductivity of the Tertiary basalts on the peninsula (1.66 ± 0.20W / mK) is about 20 percent higher than that of the contemporaneous basalts in North China (1.32 ±0.15W / mK) . This may be due to pore precipitation of silica and calcite and alteration in the Fildes Peninsula's basalts. It means, on the one hand, that during the paleovolcanic processes the strong hydrothermal activities took place on the Peninsula and, on the other hand, the thermophysical properties of basalts of oceanic and continental types are quite different.