南岭东段龙头寨群南迳组的建立及其地质时代厘定

丁辉; 巫建华; 劳玉军; 刘帅

南岭东段龙头寨群南迳组的建立及其地质时代厘定

1.
东华理工大学地球科学学院, 江西南昌 330013

2.
东华理工大学核资源与环境国家重点实验室培育基地, 江西南昌 330013

基金项目:
国家自然科学基金项目《赣南-粤北相邻区河口-南迳加里东期火山岩研究与铀成矿关系》（批准号：41662006）和中国核工业集团公司项目《中国中—新生代铀成矿作用研究》（编号：中核地计[2008]74号）

详细信息

作者简介: 丁辉(1990-), 男, 硕士, 矿产普查与勘探专业。E-mail:1281427796@qq.com

通讯作者: 巫建华(1960-), 男, 博士, 教授, 从事铀矿地质和火山地质研究。E-mail:jhwu@ecit.cn

中图分类号: P597⁺.3

收稿日期: 2016-02-01

修回日期: 2017-02-14

刊出日期: 2017-09-25

The establishment of the Nanjing Formation in Longtouzhai Group in eastern Nanling Re-gion and the determination of its age

1.
Collage of Earth Science, East China Institute of Technology, Nanchang 330013, Jiangxi, China

2.
State Key Laboratory Breeding Base of Nuclear Resources and Environment, East China Institute of Technology, Nanchang 330013, Ji-angxi, China

More Information

Corresponding author: WU Jianhua, jhwu@ecit.cn

Received Date: 01 February 2016

Revised Date: 14 February 2017

Publish Date: 25 September 2017

摘要

摘要:
南岭带东段晚奥陶世广泛发育一套浅变质岩系，称为龙头寨群。以南迳乔子山剖面和中寨剖面为层型剖面建立南迳组，并置于龙头寨群顶部。用SHRIMP法测得南迳盆地南迳组安山岩样品14个锆石U-Pb年龄数据，其²⁰⁶Pb/²³⁸U年龄变化范围为460~425Ma，年龄加权平均值为442.1±3.9Ma（MSWD=0.75）；英安岩15个锆石²⁰⁶Pb/²³⁸U年龄变化范围为450~420Ma，年龄加权平均值为439.9±3.7Ma（MSWD=0.50）。结合司前河口破火山口碎斑熔岩的SHRIMP锆石U-Pb年龄（443.6±5.4Ma（MSWD=1.3）），可将南迳组的地质时代归于晚奥陶世末期-早志留世初期。龙头寨群南迳组的建立和地质时代的厘定，不仅为龙头寨群的地质时代归入晚奥陶世-早志留世初期提供了可靠的依据，而且为南岭带东段晚奥陶世-早志留世浅变质岩系属含有火山岩的优地槽型沉积提供了证据。
- 火山岩 /
- SHRIMP锆石U-Pb年龄 /
- 晚奥陶世晚期-早志留世初期 /
- 南迳组 /
- 龙头寨群
Abstract:
The epimetamorphic rock series well developed in eastern Nanling Region is a suite of Late Ordovician epimetamorphic rock series called Longtouzhai Group that consists of dark gray, gray, celadon fine grained feldspar quartz sandstone, sericite slates, silty slate and phyllites intercalated with lenticular carbonate and sandstone. They can be subdivided upwards into Bankeng Formation, Guting Formation and Huangzhudong Formation. It is found that the original Late Jurassic Yutian Group is a suite of dark gray andes-ite, light grey dacite, porphyroclastic lava intercalated with gray dacitic tuff, volcanic brecciated tuff, celadon fine grained feldspar quartz sandstone, sericite slates, silty slate, phyllites in Siqian, Shixing (northern Guangdong) and Nanjing, Quannan (southern Jiangxi) areas. It is in conformable contact with the Huangzhudong Formation and is underlain unconformably by Middle Devonian Yunshan Formation. The volcanic rock association in the Nanjing basin is developed considerably well and the boundaries between the roof and the bottom are clearly distinguishable. The Nanjing Formation is established based on the Qiaozishan section and Zhongzhai sec-tion, and the Zhongzhai section serves as its stratotype section. The results of the SHRIMP zircon U-Pb dating indicate that the ²⁰⁶Pb/²³⁸U age range of fourteen analytical points of the rhyolite is 460~425Ma with the weighted average of 442.1 ±3.9Ma and MSWD of 0.75; the analytical points of the fifteen rhyolite porphyry samples show ages of 450~425 Ma with the weighted average of 439.9±3.7Ma and MSWD of 0.50. In combination with the zircon U-Pb age of 443.6±5.4Ma (MSWD=1.3) for porphyroclastic la-va in the Hekou (Siqian) caldera SHRIMP, the Nanjing Formation should belong to the Latest Ordovician-Early Silurian. The estab-lishment of the Nanjing Formation in Longtouzhai Group in eastern Nanling Region and the determination of its age not only pro-vide the basis for the argument that Longtouzhai Group belongs to the Late Ordovician-Early Silurian, but also offer the evidence for the opinion that the epimetamorphicd rock series of Late Ordovician-Early Silurian include volcanic miogeosynclinal type sediments in eastern Nanling Region
- volcanic rock /
- SHRIMP zircon U-Pb age /
- Late Ordovician-Early Silurian /
- Nanjing Formation /
- Longtouzhai Group

HTML全文

图 1 赣南南迳盆地地质简图

Figure 1.

下载: 全尺寸图片幻灯片

图 2 南迳盆地中寨南迳组实测剖面（A-A′）

Figure 2.

下载: 全尺寸图片幻灯片

图 3 南迳盆地乔子山南迳组实测剖面（B-B′）

Figure 3.

下载: 全尺寸图片幻灯片

图图版Ⅰ

Figure 图版Ⅰ.

下载: 全尺寸图片幻灯片

图图版

Figure 图版.

下载: 全尺寸图片幻灯片

图 4 南迳盆地安山岩和英安岩锆石阴极发光（CL）图像

Figure 4.

下载: 全尺寸图片幻灯片

图 5 南迳盆地安山岩和英安岩锆石U-Pb年龄谐和图

Figure 5.

下载: 全尺寸图片幻灯片

表 1 南迳盆地安山岩和英安岩SHRIMP锆石U-Th-Pb同位素分析结果

Table 1. SHRIMP zircon U-Th-Pb analytical results of andesite and dacite in Nanjing basin

测定点编号	²⁰⁶Pbc/10^-2	U/10^-6	Th/10^-6	²³²Th/²³⁸U	²⁰⁶Pb^*/10^-6	²⁰⁶Pb/²³⁸U年龄/Ma	²⁰⁷Pb^*/²³⁵U	±%	²⁰⁶Pb^*/²³⁸U	±%	误差相关系数
NG001（安山岩）：^206Pb/²³⁸U年龄加权平均值=442.1±3.9Ma（MSWD=0.75，n=14）
1.1	0.35	699	297	0.44	42.9	443.7±7.1	0.521	2.8	0.0713	1.7	0.598
2.1	0.33	560	285	0.53	33.6	434.1±7.0	0.519	2.6	0.0697	1.7	0.636
3.1	0.15	634	323	0.53	38.1	435.1±7.0	0.516	3.1	0.0698	1.7	0.538
4.1	0.11	1698	606	0.37	105	447.7±7.0	0.546	1.9	0.0719	1.6	0.862
5.1	0.17	558	265	0.49	33.8	438.4±7.0	0.532	2.4	0.0704	1.7	0.684
6.1	0.46	488	238	0.50	29.6	437.1±7.1	0.531	3.1	0.0701	1.7	0.542
7.1	0.71	230	126	0.56	13.9	435.1±9.6	0.509	5.8	0.0698	2.3	0.395
8.1	0.39	750	364	0.50	46.9	451.2±7.2	0.538	2.6	0.0725	1.6	0.632
9.1	0.09	732	394	0.56	45.7	451.6±7.2	0.556	2.6	0.0726	1.6	0.644
10.1	0.57	315	173	0.57	19.1	438.4±7.3	0.502	4.1	0.0704	1.7	0.425
11.1	0.33	588	240	0.42	35.7	439.2±7.1	0.548	3.2	0.0705	1.7	0.514
12.1	0.37	590	164	0.29	35.9	439.4±7.2	0.524	3.7	0.0705	1.7	0.463
13.1	0.36	380	132	0.36	23.7	450.1±7.4	0.538	3.5	0.0723	1.7	0.487
14.1	0.10	555	194	0.36	34.2	446.0±7.2	0.546	2.4	0.0716	1.7	0.692
NG101（英安岩）：²⁰⁶Pb/²³⁸U年龄加权平均值=439.9±3.7Ma（MSWD=0.50，n=14）
1.1	0.21	491	289	0.61	29.5	434.8±7.0	0.520	2.4	0.0698	1.7	0.683
2.1	0.17	698	234	0.35	42.8	443.8±7.1	0.551	2.3	0.0713	1.7	0.702
3.1	0.66	351	246	0.72	21.2	435.1±7.2	0.480	4.4	0.0698	1.7	0.389
4.1	0.37	416	227	0.56	25.7	445.7±7.3	0.537	4.1	0.0716	1.7	0.413
5.1	0.61	297	166	0.58	18.3	443.7±7.9	0.507	4.7	0.0713	1.9	0.396
6.1	0.33	755	254	0.35	45.9	439.1±7.5	0.539	2.6	0.0705	1.8	0.685
7.1	0.19	1759	504	0.30	108	445.4±6.9	0.537	2.0	0.0715	1.6	0.805
8.1	0.30	546	254	0.48	33.1	438.4±7.1	0.533	3.7	0.0704	1.7	0.450
9.1	0.24	608	257	0.44	37.0	439.7±7.1	0.522	2.5	0.0706	1.7	0.662
10.1	0.56	337	164	0.50	20.3	434.7±7.3	0.503	4.5	0.0698	1.7	0.380
11.1	0.90	307	134	0.45	18.3	427.5±8.5	0.498	5.0	0.0686	2.1	0.417
12.1	--	325	161	0.51	19.9	444.1±7.5	0.560	3.0	0.0713	1.7	0.590
13.1	0.62	501	299	0.62	31.2	447.6±7.6	0.508	4.0	0.0719	1.8	0.443
14.1	0.66	384	288	0.77	23.5	439.7±7.3	0.507	3.9	0.0706	1.7	0.436
15.1	0.38	763	364	0.49	46.2	437.3±7.0	0.526	2.6	0.0702	1.6	0.637
注：²⁰⁶Pbc和²⁰⁶Pb^∗分别表示普通铅和放射性成因铅；普通铅根据实测204Pb进行校正；误差为1σ

下载: 导出CSV

参考文献(27)

[1]	江西省地质矿产局.江西省岩石地层[M].武汉:中国地质大学出版社, 1997.
[2]	广东省地质矿产局.广东省岩石地层[M].武汉:中国地质大学出版社, 1997.
[3]	江西省地质矿产局.江西省区域地质志[M].北京:地质出版社, 1984.
[4]	广东省地质矿产局.广东省区域地质志[M].北京:地质出版社, 1984.
[5]	巫建华, 周维勋, 章邦桐.赣南-粤北晚中生代火山岩系划分和时代讨论[J].地质论评, 2000, 4:362-370. doi: 10.3321/j.issn:0371-5736.2000.04.004
[6]	巫建华, 周维勋, 章邦桐.江西及广东北部中生代晚期地层层序和时代——兼论《江西省岩石地层》中存在的问题[J].地质论评, 2002, 1:44-53. doi: 10.3321/j.issn:0371-5736.2002.01.008
[7]	巫建华, 项媛馨, 黄国荣, 等.广东北部碎斑熔岩加里东期锆石SHRIMP年龄的首获及其地质意义[J].高校地质学报, 2012, 18(4):601-608. http://www.cnki.com.cn/Article/CJFDTOTAL-GXDX201204004.htm
[8]	冀春雨, 巫建华.江西南部余田群长英质火山岩SHRIMP锆石UPb年龄及其地质意义[J].东华理工大学学报(自然科学版), 2010, 2:131-138. doi: 10.3969/j.issn.1674-3504.2010.02.003
[9]	项媛馨, 巫建华.赣南龙南地区余田群玄武岩SHRIMP锆石U-Pb年龄及其地质意义[J].地质通报, 2012, 5:716-725. doi: 10.3969/j.issn.1671-2552.2012.05.008 http://dzhtb.cgs.cn/ch/reader/view_abstract.aspx?flag=1&file_no=20120508&journal_id=gbc
[10]	王保峰, 巫建华.江西南部版石盆地火山岩SHRIMP锆石U-Pb年龄及其地质意义[J].东华理工大学学报(自然科学版), 2011, 1:18-24. doi: 10.3969/j.issn.1674-3504.2011.01.003
[11]	徐勋胜, 巫建华.江西南部蔡坊盆地火山岩系层序与地质时代[J].东华理工大学学报(自然科学版), 2010, 3:211-218. doi: 10.3969/j.issn.1674-3504.2010.03.02
[12]	巫建华, 项媛馨, 刘帅.江西南部武夷群及其地质时代[J].地层学杂志, 2011, 2:200-208. http://www.cnki.com.cn/Article/CJFDTOTAL-DCXZ201102016.htm
[13]	巫建华, 刘飞宇, 刘帅.峡江-广丰和三南-寻乌火山岩带晚中生代粗面岩SHRIMP锆石U-Pb年龄[J].地质论评, 2011, 1:125-132. http://www.cnki.com.cn/Article/CJFDTOTAL-DZLP201101019.htm
[14]	刘茜, 巫建华.江西寻乌破火山口火山-侵入杂岩SHIRMP锆石U-Pb年龄及其地质意义[J].东华理工大学学报(自然科学版), 2011, 3:231-237. doi: 10.3969/j.issn.1674-3504.2011.03.005
[15]	张浅深, 俞受鋆, 黄建辉, 等.江西南部前泥盆系的初步认識[J].地质学报, 1964, 4:388-404, 488. http://www.cnki.com.cn/Article/CJFDTOTAL-DZXE196404001.htm
[16]	陈武钦, 王漂元, 林建华.粤北始兴县城南志留纪火山岩的基本特征[J].中国西部科技, 2006, 16:29-30. doi: 10.3969/j.issn.1671-6396.2006.01.020
[17]	伍静, 王广强, 梁华英, 等.粤北大宝山矿区加里东期火山岩的厘定及其地质意义[J].岩石学报, 2014, 4:1145-1154. http://www.ysxb.ac.cn/ysxb/ch/reader/view_abstract.aspx?file_no=20140419
[18]	易立文, 马昌前, 王连训, 等.华南晚奥陶世次火山岩的发现:早古生代与俯冲有关的英安岩?[J].地球科学(中国地质大学学报), 2014, 6:637-653. http://www.cnki.com.cn/Article/CJFDTOTAL-DQKX201406001.htm
[19]	庄文明, 刘建雄, 黄友义, 等.广东马山火山岩的成岩时代[J].地质通报, 2004, 4:365-366. doi: 10.3969/j.issn.1671-2552.2004.04.010 http://dzhtb.cgs.cn/ch/reader/view_abstract.aspx?flag=1&file_no=20040470&journal_id=gbc
[20]	张喜松, 徐夕生.华南早古生代火山岩分布、岩石成因及地质意义[J].吉林大学学报(地球科学版), 2015, S1:246. http://cpfd.cnki.com.cn/Article/CPFDTOTAL-ZGKD201506001159.htm
[21]	马孝达.江西南部全南县火山岩产状及时代的讨论[J].地质论评, 1999, S1:751-755. doi: 10.3321/j.issn:0371-5736.1999.z1.106
[22]	Black L P, Kamo S L, Williams I S, et al. The Application of SHRIMP to Phanerozoic geochronology; a critical appraisal of four zircon standards[J]. Chemical Geology, 2003, 200:171-188. doi: 10.1016/S0009-2541(03)00166-9
[23]	宋彪, 张玉海, 万渝生, 等.锆石SHRIMP样品制作、年龄测定及有关现象讨论[J].地质论评2002, 48(增刊):26-30. http://www.cnki.com.cn/Article/CJFDTOTAL-DZLP2002S1006.htm
[24]	Ludwig K R. Using Isoplot/EX, version 2, a geolocronolgical tool-kit for Microsoft Excel[M]. Berkeley Geochronological Center Spe-cial Publication 1a, 1999, 47.
[25]	Ludwig K R. Squid 1.02:A User Manual[M]. Berkeley Geochrono-logical Center Special Publication, 2001:2-19.
[26]	章森桂, 严惠君, 张允白."国际年代地层表"(2013)介绍[J].地层学杂志, 2013, 3:349-352. http://www.cnki.com.cn/Article/CJFDTOTAL-DCXZ201303016.htm
①	江西省地质局区域大队. 龙南幅 1∶20万区域地质调查报告. 1970.