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南极半岛北部地质体主要为钙碱性科迪勒拉深成岩体(格雷厄姆地)。早先曾把深成岩体分成两类:一类是比分布广、但资料较少的“上侏罗火山岩群”的时代要早;另一类年代较新通常称作“安第斯侵入岩套”。放射性测定表明深成作用的活动至少是从早侏罗世至晚第三纪,在时间上与南美洲南部的深成作用相近。年龄集中在90—110Ma代表深成作用活动的高潮。从时间上和空间上可以划分出几个侵入岩带:年龄较老的一组(155—186Ma)局限在东部海岸;年龄较新的一组(45—60Ma)局限在半岛西部海岸的北部;年龄介乎其间的深成岩(70-145Ma)分布于整个半岛。现有的资料难以判断45—185Ma期间的深成作用主要是连续的还是呈多次岩浆的独立脉动。然而总体来看,随着时间的演化深成作用的中心沿半岛的横向和纵向方向上自东向西,自南向北迁移。 深成岩体的组分从辉长岩到花岗岩,西部海岸的酸性岩组分相比于东部海岸岩石更趋向于奥长花岗岩质。东部海岸的深成岩与西部同类岩石相比K2O、Rb、Th和Ba的含量高。东部海岸轻稀土元素含量高,产生Ce/Y比值高和更分馏的稀土模式。这种变化和沿半岛北海岸(太平洋)俯冲和远离海沟来源更深的钙碱性岩浆组份是一致的。从整体上说,深成岩的成因是复杂的,很难将地球化学成份变化与单个时代内的或某个区域内岩体群的简单的分异作用连系起来。科迪勒拉岩基是多期次的岩石成因模式。
The northern Antarctic Peninsula geological body is mainly calc-Cordillera pluton (Graham site). Earlier, the pluton bodies were divided into two types: the earlier is the “distribution of upper Jurassic volcanic rock masses”, which is more widespread but less informative; the other is usually referred to as the Andean intrusive rock formation ". Radiological measurements indicate that deep-seated activities are at least from the early Jurassic to the late Tertiary and are similar in time to the deep functions of southern South America. Concentration of age at 90-110Ma represents the climax of deep-seated activities. Several intruded rock bands can be divided temporally and spatially: the older group (155-186 Ma) is confined to the eastern coast; the younger group (45-60 Ma) is confined to the northern part of the western coast of the peninsula; Deep plutons (70-145Ma) are distributed throughout the peninsula. The available data are difficult to judge whether the deep function of 45-185 Ma is mainly continuous or independent pulsation of multiple magmas. Overall, however, the center of evolution over time shifted from south to north along the horizontal and vertical directions of the peninsula from east to west. The components of the deep plutons are from gabbros to granites. The acidic rocks on the west coast tend to be more ophiolitic in comparison to the eastern coast rocks. Deep plutons on the eastern coast have higher levels of K2O, Rb, Th and Ba than similar rocks in the western part of the country. The high light-earth elemental content of the eastern coast produces a rare earth pattern with high Ce / Y ratio and more fractionated. This change is consistent with the calc-alkaline magmatic components that subducted along the northern coast of the peninsula (Pacific Ocean) and further from the trench. On the whole, the cause of deep plutons is complex and it is difficult to correlate changes in geochemical composition with the simple differentiation of rock masses within a single era or within a certain area. Cordillera is a multi-stage rock pattern.