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91.
In Korea,trilobites are among the most intensively studied fossil groups in the past century and provide invaluable information about lower Paleozoic stratigraphy,paleogeography,and tectonics of the Korean Peninsula. Trilobites occur in the lower Paleozoic Joseon Supergroup of the Taebaeksan Basin which was part of the Sino-Korean Craton in the Paleozoic. The Joseon Supergroup is divided into the Taebaek,Yeongwol,and Mungyeong groups. The Taebaek and Yeongwol groups are richly fossiliferous,while the Mungyeong Group is poorly fossiliferous. Contrasting trilobite faunal contents of the Taebaek and Yeongwol groups resulted in two separate biostratigraphic schemes for the Cambrian–Ordovician of the Taebaeksan Basin. A total of 22 biozones or fossiliferous horizons were recognized in the Taebaek Group; 19 zones were established in the Yeongwol Group; and four biozones were known from the Mungyeong Group. These trilobite biozones of the Taebaeksan Basin indicate the Joseon Supergroup ranges in age from the Cambrian Series 2 to Middle Ordovician and can be correlated well with the formations of North China,South China,and Australia.  相似文献   
92.
Using 32 CMIP5(Coupled Model Intercomparison Project Phase 5) models, this study examines the veracity in the simulation of cloud amount and their radiative effects(CREs) in the historical run driven by observed external radiative forcing for 1850–2005, and their future changes in the RCP(Representative Concentration Pathway) 4.5 scenario runs for2006–2100. Validation metrics for the historical run are designed to examine the accuracy in the representation of spatial patterns for climatological mean, and annual and interannual variations of clouds and CREs. The models show large spread in the simulation of cloud amounts, specifically in the low cloud amount. The observed relationship between cloud amount and the controlling large-scale environment are also reproduced diversely by various models. Based on the validation metrics,four models—ACCESS1.0, ACCESS1.3, Had GEM2-CC, and Had GEM2-ES—are selected as best models, and the average of the four models performs more skillfully than the multimodel ensemble average.All models project global-mean SST warming at the increase of the greenhouse gases, but the magnitude varies across the simulations between 1 and 2 K, which is largely attributable to the difference in the change of cloud amount and distribution. The models that simulate more SST warming show a greater increase in the net CRE due to reduced low cloud and increased incoming shortwave radiation, particularly over the regions of marine boundary layer in the subtropics. Selected best-performing models project a significant reduction in global-mean cloud amount of about-0.99% K~(-1)and net radiative warming of 0.46 W m~(-2)K~(-1), suggesting a role of positive feedback to global warming.  相似文献   
93.
It may be safely presumed that few of us who have worked in the field as a geological surveyor would dissent in making an open confession of our unfortunate attitude towards igneous rocks particularly those of a massive form. These obstacles, as one is apt to regard them, are the unruly bodies  相似文献   
94.
As the Gorge District of the Yangtze is one of the few areas in China that can deservedly boast before the world its scenic grandeur as well as beauty, it has been long felt that a systematic account of its geological conditions would open another aspect of interest to the scientific travellers. There are already on the record the observations of Pumpelly, Richthofen, Abendanon, Willis and Blackwelder, Noda and others; but the results of their work, important as they are in certain respects, seem to ind...  相似文献   
95.
李四光  仲揆 《地质学报》1923,2(Z2):51-94
本篇分为三节:第一节论研究(竹廷)蜗之方法及其各部分之名称;并猎取古生物学家迄今历史之结果而加以批评。第二节专述中国北部已发见之(竹廷)蜗。第三节讨论本篇所述各种(竹廷)蜗生存之时代及其棲息流徙之情形。  相似文献   
96.
Eleven years ago when this society held its Third General Meeting I had the opportunity of calling your attention to certain strange deposits and topographical features that came under my notice in certain parts of North China. I showed you a number of st  相似文献   
97.
INTRODUCTION The geology of Szechuan and the adjoining regions has been studied by the pioneer geologists such as F. von Richthofen~1, L. von Loczy~2, B. Willis and E. Blackwelder~3 and E. C. Abendanon~4 respectively on the northern and eastern  相似文献   
98.
GENERAL FEATURES. The Upper Yangtze valley includes the valleys of the main river and its chief tributaries. Chinshactiang (金沙江) and Yalungchiang (雅龍江) flow in north-south courses through Hsikang, Eastern Tibet, and turn to NEE  相似文献   
99.
In the days when the uniformitarians triumphantly fought against the catastrophists, it was apparently thought by the leaders of the rising school that the ebb and flow of the oceanic water had been going on indefinitely all over the surface of our planet for an untold length of time. Beyond this, little was then  相似文献   
100.
李四光  赵亚增 《地质学报》1926,5(2):107-112
During his epoch-making exploration in China, von Richthofen~1 divided the Palaeozoic coal-bearing series in Shansi into 3 subdivisions:  相似文献   
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