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Removing the Tertiary and Quaternary Periods whilst conserving the Paleogene and Neogene Periods in The Geological Timescale 2004 caused a storm of protest. One response was to advocate restoring an enlarged Quaternary and consigning the Neogene to a minor role within the Tertiary. Amongst an array of practical, traditional, sentimental and anthropocentric reasons for this response, the one hard-core justification was that the rigidly nested hierarchy of the geological timescale must be preserved.The central objective of this paper is conserving the historically legitimate, Miocene-present, Neogene Period and System. There are two options for conserving the Quaternary concurrently with the Neogene: (i) an inclusive compromise in a flexible hierarchy, and (ii) an upgrading of Pliocene and Pleistocene divisions to the level of epoch.In the inclusive compromise there coexist alternative pathways through the hierarchical ranks. Thus geohistorians and biohistorians have two options for traversing the hierarchy from era to age, as in this example using the hierarchical positioning of the Calabrian Age and Stage:either Cenozoic [era]↔Neogene [period]↔Pleistocene [epoch]↔Calabrian [age],or Cenozoic [era]↔Quaternary [subera]↔Pleistocene [epoch]↔Calabrian [age].We reaffirm that the inclusive compromise is entirely viable. In so doing we (i) challenge the necessity of the rigidly nested hierarchy, which should be capable of a little flexibility; (ii) reject all analogies of the arbitrary and conventional chronostratigraphic hierarchy with three natural biological hierarchies; (iii) reaffirm the integrity of the Neogene extending to the present; and (iv) see no reason to doubt the harmonious coexistence of the two options preserving the Quaternary and Neogene traditions in an orderly working and stable time scale.In the alternative schema conserving the Neogene, divisions of the Pliocene and Pleistocene are upgraded, so that the Late Pleistocene, Early Pleistocene and Late Pliocene Epochs comprise the Quaternary Subperiod, itself equivalent to Late Neogene. The inflexibly nested hierarchy is preserved but the Tertiary is lost. 相似文献
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江南古陆变质基底地层年代的修正和武陵运动构造意义 总被引：1，自引：0，他引：1
江南古陆变质基底的研究中,最突出的基础地质问题依然是地层年代的精确标定。地层年代标定涉及到成矿地层的划分和对比及其构造演化的时限,也直接影响层控矿床找矿中涉及的基础地质问题。在最新的中国地层年表中,前寒武纪地层对比和构造背景解释已发生重大变化。本文依据扬子块体和华夏块体新元古代地层中最新的系列锆石U—Pb测年结果,初步揭示“江南古陆”变质基底地层火山事件和分布范围。结合全球格林威尔造山运动基本特征,对江南古陆变质基底地层年代的修正将有利于重新厘定江南造山带的成矿背景,提供层控矿床基础年代地层资料,为新的矿产资源大调查服务。 相似文献
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扬子区震旦纪地层序列和南、北方震旦系对比 总被引：18，自引：7，他引：18
198 2年“晚前寒武纪地层分类命名会议”决议“震旦系是青白口系之上的晚元古代最上部的一个年代地层单位 ,以三峡地区的剖面为代表 ,暂以莲沱组底界为底界”。但从区域性对比和同位素年代地层学分析 ,莲沱组底至黄陵花岗岩的侵蚀面之间有约 10 0 Ma的沉积缺失 ,莲沱组和南沱组也不能代表 75 0～ 6 6 0 Ma间的沉积历史。峡东地区震旦系下部地层不完整是显而易见的。本文赞同修订震旦系的含义 ,以下冰碛层 (古城组或铁丝坳组 )之底为震旦系的底界 ,年龄为 70 0 Ma。朝鲜飞浪洞组可与古城组、大塘坡组和南沱组对比 ,祥原系及辽南、徐淮地区的相当地层属“南华冰期”前的沉积地层。建议震旦系之下至青白口系顶 (85 0 Ma)之间建立辽南系 ,从而完善我国晚元古代年代地层框架 相似文献
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江南古陆中段湖南益阳地区沧水铺群发育在冷家溪群和板溪群之间,其在地层柱中的位置一直是中国地质学家解疑江南造山带何时启动的关键层位。笔者在沧水铺群中的火山集块岩中获得锆石SHRIMP U-Pb年龄(821±13)Ma,再次验证了沧水铺群中的火山岩是820 Ma武陵运动之前的火山事件的产物,与武陵运动的启动有关,也说明该期火山岩与冷家溪群中大量的火山凝灰岩为同一构造运动的产物。 相似文献
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Detrital Zircon Dating of Meso- and Neoproterozoic Rocks in North China and Its Implications 总被引：4，自引：0，他引：4
Gao Linzhi Liu Pengju Yin Chongyu Zhang Chuanheng Ding Xiaozhong LIU Yanxue Song Biao 《《地质学报》英文版》2011,85(2):271-282
New dates from Meso- and Neoproterozoic strata contribute to the recently defined Precambrian stratigraphical timescale of China agreed by the Subcommission on the Precambrian System, and the National Commission on Stratigraphy of China on Nov. 24, 2009. First, the age range of the Changcheng System, including the Changzhougou, Chuanlinggou, Tuanshanzi and Dahongyu formations has been constrained to 1.8–1.6 Ga. Second, the Jixian System including the Gaoyuzhuang, Yangzhuang, Wumishan, Hongshuizhuang and Tieling formations has been constrained to 1.6–1.4 Ga. Third, an as-yet unnamed (undefined) system (1.4–1.0 Ga) is only developed in the Xiamaling Formation at the Jixian section, Tianjing. Fourth, the Qingbaikou System, including the Luotuoling and Jing’eryu formations has been constrained to 1.0–0.78 Ga. Fifth, the Nanhuan System ranges between 780–635 Ma, and the Sinian System is within 635–542 Ma. However, according to a series of SHRIMP U-Pb dates from the late Precambrian in the Jiangnan Orogen Belt in South China Platform, the constrained strata will be redefined as in the upper part of the Qingbaikou System. To aid global geodynamics, it is useful to denote a late Precambrian section with unified, precise and high-precision chronological dating; this is here defined in North China Block and Jiaoliao-Korean Block. However, the Neoproterozoic Qingbaikou study in North China will be influence in whole Meso- and Neoproterozoic in the Jiangnan Orogenic Belt in between the Yangtze Block and the Cathaysia Block in South China. 相似文献
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