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地史图上包含着非常丰富的信息,通过研究阿拉斯加区域地质演化史有助于弄清楚中南阿拉斯加的地形地貌特征。在梳理地质年代的划分以及阿拉斯加地史图的基础上,对各时期阿拉斯加地质事件进行了分析。指出:(1)晚古生代时期的阿拉斯加存在的部分极少,都在非常温暖的纬度地区。亚历山大地体和兰格利亚地体正在北美克拉通西部的赤道附近形成。(2)晚三叠纪到早侏罗纪时期的阿拉斯加存在的部分不多,但是仅存在部分已随北美克拉通的其他部分向北移动。由4个独立的地体组成的兰格利亚复合体也已向北向东,朝着北美克拉通的方向迁移。(3)晚侏罗纪至早白垩纪时期的阿拉斯加,兰格利亚复合体靠近北美克拉通相当于现在加利福尼亚和俄勒冈附近的地区(当然,彼时它们还不存在)。北美洲本身移动到比现在的位置往北得多的地方。阿拉斯加北部地区开始分离并从加拿大北部开始旋转移动。(4)晚白垩纪时期的阿拉斯加,兰格利亚地体也已经贴附到阿拉斯加之上,这样就使得北美克拉通的西北部开始有了组装阿拉斯加的框架了。(5)始新世时期的阿拉斯加据信已与现在的形状非常相似。威廉王子地体和亚库塔特地体已由洋盆沉积物形成;德奈利断层以及其他断层已处于现在的位置;阿拉斯加的西部已向南旋转到当前的纬度位置。(6)中南阿拉斯加地史剖面系列图,标示了过去2.3亿年中南阿拉斯加地面以下地体活动状况。
Geostatistics contains a wealth of information, through the study of the history of the geological evolution of the region of Alaska helps to clarify the topography of Alaska in Central South China. Based on the division of geologic age and the geostationary map of Alaska, the geological events in Alaska during each period are analyzed. It is pointed out that: (1) There are very few parts of Alaska during the Late Paleozoic, all in very warm latitudes. The Alexandria and Langerian terrain are forming near the equator in western North Cratonia. (2) There are not many parts of Alaska during the Late Triassic to Early Jurassic, but only parts of it have moved northward along with the rest of North American craton. The Langelé complex, which consists of four separate terrains, also migrates north-east and north-east toward Cratun. (3) Late Alaskan to Early Cretaceous Alaska, the Langelé complex is close to the North American craton equivalent to the areas now around California and Oregon (of course, they did not exist at that time). North America itself moved much further north than it is now. Northern Alaska began to separate and start rotating movement from northern Canada. (4) In the late Cretaceous period of Alaska, the Langerian landmass was also attached to Alaska, thus beginning the assembly of Alaska in the northwestern part of North Cratonia. (5) The Alaskan Eocene beliefs have been very similar to the present shape. The Prince William terrain and the Yakut terrain have been formed by oceanic sediments; the Denali fault and other faults are now in their present position; the western part of Alaska has rotated south to the current latitude. (6) A series of maps of Alaskan geosyncline profiles in central and southern China mark the status of terrestrial activities below the ground level of Alaska in central and southern China over the past 230 million years.