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南极横断山脉是一条新生代形成的线性地垒,其内出露许多上元古界——下古生界沉积地层和构造带。早期的研究将它统称为罗斯超群。该超群受到早古生代罗斯造山运动的变形,并被上古生界比肯亚超群底部的侵蚀面所削蚀。进一步的工作表明,罗斯“超群”可以分为前寒武系和早古生界两套地层。 南极横断山脉所有含化石的下古生界岩石时代都为寒武纪,但各组之间以不整合相接,该套地层在山脉中部厚度超过8000米。在阿根廷岭和南极横断山脉中部出露下寒武统古杯灰岩,而在惠彻韦冰原岛峰则见有这种灰岩的漂砾。中寒武统碎屑岩和碳酸盐岩在这里也分布广泛,但在整个山脉地区则分布零星。已知含化石的上寒武统地层仅见子维多利亚地北部,但彭萨科拉和毛德皇后山不含化石的地层其时代也可能属晚寒武世。晚于寒武纪的标准早古生代化石还未见到,但在维多利亚地北部也许还有内普丘恩岭出露的粗碎屑岩层其时代可能属奥陶纪。 寒武系地层的底部一般不整合于更老的岩层之上,而且上下沉积环境变化很大。下部是“杂砂岩”型岩石,上覆的则为碳酸盐岩——石英岩——泥岩组合。由于目前所使用的罗斯超群包括了不整合面上下两套地层,所以引起了许多麻烦,应当予以废除。本文指出,罗斯层序主要是一套寒武系地层,它不整合于比尔德莫尔或更老的造山带之上,并在晚寒武世早期——早奥陶世的罗斯造山运动中发生过褶皱。对于象晚于罗斯造山运动的内普丘思群,就不属于罗斯层序了。这个划分方案可能不适用于维多利亚地北部,后者是与南极横断山脉近于平行的另一个沉积——构造带。
The Antarctic Hengduan Mountains is a linear basement formed by the Cenozoic, exposing many Paleoproterozoic-Lower Paleozoic sedimentary strata and structural belts. Earlier research referred to it as Rose Maria. This metamorphism was distorted by the Early Paleozoic Ross orogeny and was eroded by the erosion of the bottom of the Upper Paleozoic than the Kenyonia. Further work shows that Rose “superior ” can be divided into two sets of Precambrian and Early Paleozoic strata. All fossil-bearing Lower Paleozoic rocks of the Antarctic Trail are of the Cambrian age, but unconformity is encountered between the groups. The set of strata has a thickness of more than 8,000 meters in the central part of the range. The lower Cambrian paleotymas were exposed in the Argentine Ridge and in the middle of the Antarctic Traverse, while the limestone boulders were found on the summit of the island of Whitschweb. Middle Cambrian clastic rocks and carbonate rocks are also widespread here, but sporadically throughout the mountain range. It is known that fossil-bearing Upper Cambrian strata can only be found in the northern part of Victoria, but the fossil-free strata of Pensacola and Queen Maude may also be Late Cambrian. Standard Early Paleozoic fossils that were later than the Cambrian have not yet been seen, but perhaps the crustal strata exposed in the Neptuneqen in the northern part of Victoria may have dated to Ordovician. The bottom of the Cambrian strata are generally not integrated with older rock formations, and the upper and lower sedimentary environments vary widely. The lower part is a “sandy sand” type of rock, overlying a carbonate-quartzite-mudstone combination. Since the current Rose Supercomputing System includes two sets of unconformity upper and lower strata, it caused a lot of trouble and should be abolished. This article points out that the Rose sequence is mainly a Cambrian strata that is not integrated with Bildermore or the older orogenic belt. During the Early Late Cambrian-Early Ordovician Ross orogeny Folds have occurred. For the Nepucci group later than the Rose orogen, it does not belong to the Rose sequence. This division scheme may not apply to the northern part of Victoria, which is another sedimentary-tectonic belt parallel to the Antarctic Transect.