Activation of northern margin of the North China Craton in Late Paleozoic:Evidence from U-Pb dating

来源 :Chinese Science Bulletin | 被引量 : 0次 | 上传用户:alexl
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
LA-MC-ICPMS U-Pb dating has been performed on detrital zircons from the Upper Carboniferous Tai-yuan Formation (N-8) in the Ningwu-Jingle Basin, west of the North China Craton (NCC). The ages of 72 detrital zircon grains are divided into three groups: 303―320 Ma (6 grains), 1631―2194 Ma (37 grains, peaked at 1850 Ma), 2318―2646 Ma (29 grains, peaked at 2500 Ma). Detrital zircons of Group 2 and Group 3 were likely derived from the basement of the NCC. Group 1 zircons exhibit 176Hf/177Hf ratios ranging from 0.281725 to 0.282239, with corresponding negative εHf(t) values of -12.4―-30.3 and old Hf model ages of 1.4―2.2 Ga. These characteristics show a strong resemblance to those of Carboniferous igneous zircons from the Inner Mongolia Paleo-uplift (IMPU) on the northern margin of the NCC, but differ significantly from those of the Xing-Meng Orogenic Belt, suggesting that the source of the Tai-yuan Formation partly came from the IMPU. All detrital zircons of Group 1 have relatively high Th/U ratios (> 0.67), indicating a magmatic origin. The mean age (304 ± 6 Ma) of the two youngest grains is close to the depositional age of the Taiyuan Formation, suggesting a strong tectonic uplift and magmatism in the IMPU during the Late Carboniferous. This paper provides important geological evidence for the activation of the northern margin of the NCC in the Late Paleozoic. LA-MC-ICPMS U-Pb dating has been performed on detrital zircons from the Upper Carboniferous Tai-yuan Formation (N-8) in the Ningwu-Jingle Basin, west of the North China Craton (NCC). The ages of 72 detrital The zircon grains are divided into three groups: 303-320 Ma (6 grains), 1631-2194 Ma (37 grains, peaked at 1850 Ma), 2318-2646 Ma (29 grains, peaked at 2500 Ma). Detrital zircons of Group 2 and Group 3 were likely derived from the basement of the NCC. Group 1 zircons exhibit 176Hf / 177Hf ratios ranging from 0.281725 to 0.282239, with corresponding negative εHf (t) values ​​of -12.4--30.3 and old Hf model ages of 1.4-2.2 Ga. These characteristics show a strong resemblance to those of Carboniferous igneous zircons from the Inner Mongolia Paleo-uplift (IMPU) on the northern margin of the NCC, but differ significantly from those of the Xing-Meng Orogenic Belt, suggesting that the source of the Tai-yuan Formation partly came from the IMPU. All detrital zircons of Group 1 have relative ly high Th / U ratios (> 0.67), indicating a magmatic origin. The mean age (304 ± 6 Ma) of the two youngest grains is close to the depositional age of the Taiyuan Formation, suggesting a strong tectonic uplift and magmatism in the IMPU during the Late Carboniferous. This paper provides important geological evidence for the activation of the northern margin of the NCC in the Late Paleozoic.
其他文献
广东省深圳市坪山实验学校麒麟文学社成立于2012年,是学校最有活力、最具文化特色的学生社团之一,现有社员一百余人。文学社以“营造校园文化氛围,培养文学创作新人”为宗旨,
一、当前我国高中体育教学所面临的问题(一)体育教学观念落后由于受当前应试教育大环境的局限,我国高中学校师生的应试教育思想已经根深蒂固,这也导致我国高中学校体育教学长
对儿童腺样体肥大的估计往往与后鼻镜检查所见不符,由于儿童不合作,有时检查难以进行,根据父母描述而决定手术,往往是疗效不佳的原因。本文作者进行90例腺样体切除术,女53例
肺热病是以风热病毒犯肺,热壅肺气,肺失清肃,以骤起发热,咳嗽、烦渴、胸痛为主要表现的内脏瘅(热)病类疾病;其中痰热壅肺证是由于痰热交结壅积于肺,以发热口渴、咳嗽气喘、
高中生物教学是一门重要的理科类学科教学,随着近些年来的新课改的启动,高中生物教学在不断探索,取得了不错的成绩。但是仍有很多的缺点和不足有待改进,针对高中生物教学中存
中耳炎症,特别是咽鼓管功能不良,不仅可导致鼓膜松弛部收缩囊形成,而且可使紧张部收缩。收缩囊可侵入鼓室诸隐窝和上鼓室内形成胆脂瘤。作者将收缩囊分为局限型和鼓膜紧张部
今报道一例新生儿败血症,从脑脊液和血液中均检出非液化莫拉菌(M.nonliquefaciers)。一、病例 患儿,男,出生8天,因发热7天伴哭闹、拒乳,于1998年8月20日入院。患儿因胎头吸引助产,有头皮局部创伤,生后第二天出现
刚毕业时,我被分配到了一所偏远的乡镇卫生院工作。这对于曾经的学校记者团团长且多次在报刊上发表文章的我来说无疑是个晴天霹雳。我曾何等踌躇满志地想留在市级或县级医院里大显身手啊!可我无法摆脱命运的安排。  那所乡镇卫生院坐落在一个依山傍水的地方。小镇上的居民木讷又保守。初次看到小镇上凌乱的街道和破败的房屋,我的心里立即涌出被流放到西伯利亚般的无奈和心酸。真是永无出头之日了!我这么一想,更觉得心灰意冷。
摘 要  小组学习是一种较为新颖的教学方法,适合于很多学科的课堂教学。小组学习可以有效的提升学生的参与性,在讨论中思考学习内容。阅读是语文教学中必不可少的教学环节,初中阶段加强学生的阅读能力是语文教师必不可少的教学内容。语文阅读加强学生对课文内容的理解和把握,养成一个良好的阅读习惯,同时从小就培养好学生良好的语文阅读能力可以有效提高学生的学习效率,强化学生对课文内容的分析和掌握,为学生未来的发展奠
目的:建立气道炎症模型豚鼠血浆中花生四烯酸(AA)的测定方法,考察野鸢尾黄素降低气道炎性反应的作用。方法:以烟熏配合合胞病毒滴鼻制造气道炎症豚鼠模型,以AA-d8为内标,采用