Zircon U-Pb geochronology of basement metamorphic rocks in the Songliao Basin

来源 :Chinese Science Bulletin | 被引量 : 0次 | 上传用户:kissonegougou
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
Zircon LA-ICP MS U-Pb dating of six metamorphic rocks and a metagranite (breccia) from southern basement of the Songliao Basin are reported in order to constrain the formation ages of basement. The basement metamorphic rocks in the Songliao Basin mainly consist of metagabbro (L45-1), amphibolite (SN117), metarhyolitical tuff (G190), sericite (Ser) schist (N103), chlorite (Chl) schist (T5-1), biotite (Bi)-actinolite (Act)-quartz (Q) schist (Y205), and metagranite (L44-1). The cathodoluminesence (CL) images of the zircons from metagabbro (L45-1) and metagranite (L44-1) indicate that they have cores of magmatic origin and rims of metamorphic overgrowths. Their U-Pb isotopic ages are 1808±21 Ma and 1873±13 Ma, respectively. The zircons with oscillatory zoning from amphibolite (SN117) and Chl schist (T5-1), being similar to those of mafic igneous rocks, yield ages of 274 ± 3.4 Ma and 264 ± 3.2 Ma, re-spectively. The zircons from metarhyolitical tuff (G190) and Ser schist (N103) display typical magmatic growth zoning and yield ages of 424 ± 4.5 Ma and 287 ± 5.1Ma, respectively. Most of zircons from Bi-Act-Q schist (Y205) are round in shape and different in absorption degree in the CL images, implying their sedimentary detritals. U-Pb dating yield concordant ages of 427 ± 3.1Ma, 455 ± 12 Ma, 696 ± 13 Ma, 1384±62 Ma, 1649±36 Ma, 1778±18 Ma, 2450±9 Ma, 2579±10 Ma, 2793±4 Ma and 2953±14 Ma. The above-mentioned results indicate that the Precambrian crystalline basement (1808―1873 Ma) exists in the southern Songliao Basin and could be related to tectonic thrust, and that the Early Paleozoic (424―490 Ma) and Late Paleozoic magmatisms (264―292 Ma) also occur in the basin basement, which are consistent with the ages of the detrital zircons from Bi-Act-Q schist in the basement. Zircon LA-ICP MS U-Pb dating of six metamorphic rocks and a metagranite (breccia) from the southern basement of the Songliao Basin are reported in order to constrain the formation ages of basement. The basement metamorphic rocks in the Songliao Basin main consist of metagabbro Methotrexate tuff (G190), sericite (Ser) schist (N103), chlorite (Chl) schist (T5-1), biotite (Bi) -actinolite (Act) -quartz ) the cathodoluminesence (CL) images of the zircons from metagabbro (L45-1) and metagranite (L44-1) indicate that they have cores of magmatic origin and rims of metamorphic overgrowths (L44-1) Their U-Pb isotopic ages are 1808 ± 21 Ma and 1873 ± 13 Ma, respectively. The zircons with oscillatory zoning from amphibolite (SN117) and Chl schist (T5-1), are similar to those of mafic igneous rocks, yield ages of 274 ± 3.4 Ma and 264 ± 3.2 Ma, re-spectively. The zircons from metarhyolitical tuff (G190) and Ser schist (N103) display Typical magmatic growth zoning and yield ages of 424 ± 4.5 Ma and 287 ± 5.1Ma, respectively. Most of zircons from Bi-Act-Q schist (Y205) are round in shape and different in absorption degree in the CL images, implying their sedimentary U-Pb dating yield concordant ages of 427 ± 3.1 Ma, 455 ± 12 Ma, 696 ± 13 Ma, 1384 ± 62 Ma, 1649 ± 36 Ma, 1778 ± 18 Ma, 2450 ± 9 Ma, 2579 ± 10 Ma, 2793 ± 4 Ma and 2953 ± 14 Ma. The above-mentioned results that that the Precambrian crystalline basement (1808-1873 Ma) exists in the southern Songliao Basin and could be related to tectonic thrust, and that the Early Paleozoic (424-490 Ma) and Late Paleozoic magmatisms (264-292 Ma) also occur in the basin basement, which are consistent with the ages of the detrital zircons from Bi-Act-Q schist in the basement.
其他文献
本研究构建了SARS冠状病毒纤突蛋白(S)重组杆状病毒(rBac-SS)。SDS-PAGE及Western-Blot分析表明约190 Ku左右的重组SARS纤突蛋白(rSS)在rBac-SS感染sf9昆虫细胞获得表达,并具
从课堂实施、师资、和教材实际出发,探讨开展生物化学双语教学存在的问题及今后应采取的措施。寻找切入点,探索有效途径,以使双语教学取得满意的教学效果。 From the implem
文章结合已运营了近20年的某桁架拱桥静载试验,介绍了桁架拱桥承载能力评定过程中的调查与检测、桥梁结构验算、静载试验及承载能力评定,较详细地阐述了静载试验方法及试验结
目的 探讨自发凋亡率、p27kip1在人膀胱移行细胞癌中表达的临床意义.方法采用TUNEL法检测自发凋亡细胞,用S-P法检测p27kip1基因在50例膀胱移行细胞癌中的表达,分析各检测指标在上述标本中的表达及与膀胱移行细胞癌分级、临床分期间的关系.结果在膀胱移行细胞癌中,自发凋亡率AI均数为(3.0±1.5)%,p27kip1基因的阳性表达率为58.0%(29/50).其二者的阳性表达均随膀胱癌分
The influence of basic horizontal current on the propagation of internal wave in the non-homogeneous ocean is studied in this paper. By means of pseudo-static h
目的:基于睾丸扭转建立兔睾丸缺血再灌注损伤模型,探索缺血预处理对睾丸缺血再灌注损伤兔的睾酮水平及生精细胞凋亡的影响。方法:雄性新西兰大白兔15只,随机分为3组:A组(对照
目的探讨子宫良性疾病行子宫切除术中同时切除双侧输卵管是否加重子宫切除对卵巢储备功能的负面影响。方法因子宫良性疾病行子宫切除患者60例,术中同时切除双侧输卵管患者30
为庆祝中国共产党成立97周年、推进“两学一做”学习教育常态化制度化和“清廉机关”建设,6月28日上午,省档案局(馆)开展了庆祝建党97周年暨迎“七一”系列主题党日活动.驻省
期刊
摘 要  与普通院校相比,中职院校在教学方面更强调培养学生的实践能力,具有较强的专业性、实用性以及针对性。近年来随着社会经济与技术的发展,社会对计算机人才的需求量激增,为了满足社会的实际需求,中职学校计算机教学应当积极开展创新改革,使教学工作更加高效,真正培养出具有较强计算机能力的实用型人才。任务驱动法就是一种具有创新性的教学手段,将其应用到中职计算机教学中有着重要的现实意义。文中将对中职学校计算
党的十八大提出“完善基层民主制度…,保障职工参与管理和监督的民主权利。”高校民主管理工作是高校行政管理工作的重要组成部分,为了解高校民主管理状况,本课题组结合研究课题