科科斯脊玄武岩斜长石矿物化学及地质意义

葛振敏; 鄢全树; 赵仁杰; 施美娟

doi:10.3969/j.issn.0253-4193.2020.07.008

科科斯脊玄武岩斜长石矿物化学及地质意义

doi: 10.3969/j.issn.0253-4193.2020.07.008

葛振敏^1,,
鄢全树^{1, 2, 3, ,},
赵仁杰^{1, 3},
施美娟¹

1.
自然资源部第一海洋研究所海洋沉积与环境地质重点实验室，山东青岛 266061
2.
青岛海洋科学与技术试点国家实验室海洋地质过程与环境功能实验室，山东青岛 266061
3.
山东科技大学地球科学与工程学院，山东青岛 266590

基金项目: 国家重点研发计划（2017YFC1405502）；国家自然科学基金（41776070）；山东省泰山学者工程项目。

详细信息

作者简介:
葛振敏(1992—)，女，山东省日照市人，从事海洋地质研究。E-mail：zhenminge@126.com

通讯作者:
鄢全树，男，研究员，主要从事海底岩浆活动与构造演化方面研究。E-mail：qsyan@fio.org.cn

中图分类号: P736.4
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出版历程
- 收稿日期: 2019-07-25
- 修回日期: 2019-10-14
- 网络出版日期: 2020-11-18
- 刊出日期: 2020-07-25

Mineral chemistry and geological significance of plagioclases hosted by basalts from the Cocos Ridge

Ge Zhenmin^1
,,
Yan Quanshu^{1, 2, 3
, ,},
Zhao Renjie^{1, 3},
Shi Meijuan¹

1.
Key Laboratory of Marine Sedimentology and Environmental Geology, First Institute of Oceanography, Ministry of Natural Resources, Qingdao 266061, China
2.
Laboratory for Marine Geology, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao 266061, China
3.
College of Earth Science and Engineering, Shandong University of Science and Technology, Qingdao 266590, China

摘要

摘要: 综合大洋钻探计划(IODP) 334和344航次在U1381站位处的两个钻孔(A孔和C孔)获得了中美洲西海岸外科科斯脊基底拉斑玄武岩，对其岩浆过程开展研究可为理解其岩石成因提供重要依据。本文对科科斯脊玄武岩中斜长石斑晶和微晶进行了详细的原位主微量元素分析，结果表明，斜长石种属为培长石、拉长石及少量中长石。部分斜长石斑晶具有正环带结构；但多数斜长石斑晶不具有明显环带，仅从核部到边部存在微弱的成分变化。斜长石斑晶与微晶的微量元素差别较大：斜长石斑晶富集轻稀土和大离子亲石元素、亏损高场强元素，且具有明显的Eu正异常；斜长石微晶不相容元素含量通常高于斜长石斑晶。根据斜长石温度计计算获得斜长石斑晶结晶温度为1 050～1 253℃，斜长石微晶结晶温度为866～1 033℃。基于以上特征，推测斜长石斑晶核部是相对原始岩浆的产物，而斑晶边部以及微晶是演化岩浆的结晶产物。斜长石斑晶的成分变化及熔蚀麻点结构是由于岩浆补给及岩浆减压上升造成的。最后，本研究推测科科斯脊基底玄武岩来自于开放的岩浆房，且岩浆房内可能存在原始岩浆的不断注入及岩浆对流。
- 拉斑玄武岩 /
- 斜长石 /
- 矿物化学 /
- 微量元素 /
- 科科斯脊 /
- 岩浆作用
Abstract: During the Integrated Ocean Drilling Program (IODP) Expeditions 334 and 344, tholeiitic basalt basement samples of the Cocos Ridge offshore central America were drilled in holes U1381A and U1381C at Site U1381. Studying on these samples will provide some important clues for understanding their petrogenesis. In this study we carried out in-situ major and trace elements analysis for plagioclase phenocrysts and microlites hosted by these basalt samples. The results show that plagioclases are bytownite, labradorite, with a small number of andesine. Some of the plagioclase phenocrysts show positive compositional zoning, while others only have weak compositional changes from the core to the rim of the phenocrysts. The trace element compositions of plagioclase phenocrysts and microlites are quite different. The plagioclase phenocrysts are enriched in light rare earth elements and large ion lithophile elements, depleted in high field strength elements, and have obvious positive Eu anomalies. The contents of most incompatible elements of microlites are higher than those of phenocrysts. We used the classical igneous plagioclase thermometer to calculate the crystallization temperature of plagioclase phenocrysts and microlites as follows, i.e., 1 050−1 253℃ for plagioclase phenocrysts, and 866−1 033℃ for plagioclase microlites. Finally, we suggest that the core of plagioclase phenocrysts is crystallized from earlier relatively primitive magma, while the rim of the phenocrysts and microlites are crystallization products of continuous evolved magma compositions. The corrosion structure and positive compositional zoning of plagioclase phenocrysts may be mainly caused by some processes such as upwelling decompression and magma recharging. We suggest that the Cocos Ridge basaltic magma was originated from a magma chamber with continuous injection and convection of primitive magma.
- basaltic rocks /
- plagioclase /
- mineral chemistry /
- trace element /
- Cocos Ridge /
- magmatism

HTML全文

图 1 科科斯脊及邻近地区简要地质图及IODP U1381站位位置^[2-3] (a)，U1381A孔和C孔岩芯柱状简图(mbsf：海底以下深度，单位：m)^[4-5] (b)

a 图中红色方框为取样区域，EPR：东太平洋海隆，CNS：科科斯-纳兹卡扩张中心。b 图中红色带括号数字指示样品位置，对应样品编号为：(1)1381A-14R2, (2)1381A-16R2, (3)1381A-18R2, (4)1381A-20R2, (5)1381A-26R1, (6)1381C-13X1。(1)～(5)来自U1381 A孔，(6)来自U1381 C孔

Fig. 1 Tectonic setting of the Cocos Ridge and the adjacent area^[2-3] (a), schematic lithostratigraphic summary of holes U1381A and C^[4-5](mbsf: meter below seafloor) (b)

In the figure a, the red box in the map refers to the Expedition 334 and 344 drilling area, EPR: Eastern Pacific Rise, CNS: Cocos-Nazca Spreading Center. The numbers in red brackets in the figure b indicate the position of the sample, and the corresponding sample number is (1)1381A-14R2, (2) 1381A-16R2, (3)1381A-18R2, (4)1381A-20R2, (5)1381A-26R1, (6)1381C-13X1. Of them, number (1)−(5) are from Hole U1381 A, and number (6) is from Hole U1381 C

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图 2 典型斜长石矿物的背散射电子(BSE)图像

a. 样品1381A-14R2中斜长石斑晶；b. 样品1381A-16R2中斜长石斑晶；c-d. 样品1381C-13X1中斜长石斑晶；e. 样品1381A-14R2中斜长石微晶；f. 样品1381C-13X1基质中斜长石微晶。红色点为电子探针测试点，pl：斜长石；px：辉石

Fig. 2 Backscattering electron (BSE) images of representative plagioclases

a. Plagioclase (pl) phenocryst in sample 1381A-14R2; b. plagioclase phenocryst in sample 1381C-16R2; c-d. plagioclase phenocrysts in sample 1381C-13X1; e. plagioclase microlites in sample 1381A-14R2; f. plagioclase microlites in the matrix of sample 1381C-13X1. The red dots are electron probe test points; pl: plagioclase; px: pyroxene

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图 3 斜长石化学成分分类图

A. 钠长石；B. 奥长石；C. 中长石；D. 拉长石；E. 培长石；F. 钙长石；G. 透长石；H. 歪长石

Fig. 3 Classification of plagioclase compositions

A. Albite; B. oligoclase; C. andesine; D. labradorite; E. bytownite; F. anorthite; G. sanidine; H. anorthoclase

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图 4 U1381站位玄武岩中斜长石的稀土元素球粒陨石标准化图解（球粒陨石数据来自文献[31]）

Fig. 4 Chondrite-normalized REE patterns of the plagioclases in basalts from Site U1381 (CI chondrite values cited from reference [31])

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图 5 U1381站位玄武岩中斜长石原始地幔标准化蛛网图（原始地幔数据来自于文献[32]）

Fig. 5 Primitive mantle normalized trace element spidergram of the plagioclases in basalts from Site U1381(primitive mantle values after reference [32])

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图 6 斜长石中FeO^T、TiO₂、La随An值变化图解

Fig. 6 Plots of An versus FeO^T、TiO₂、La of plagioclases

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图 7 典型斜长石斑晶从核部到边部元素组成变化图解

横坐标1~6代表从核部到边部，具体测试点位见图2a和图2c

Fig. 7 Schematic diagram of major oxides compositional variations or trace element concentrations of typical plagioclase phenocrysts

Numbers 1– 6 refer to core and rim of phenocrysts, see Fig.2a and Fig.2c for the electron probe test points

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表 1 斜长石电子探针分析平均组分(wt%)

Tab. 1 EPMA compositions (average values, in wt %) of plagioclases

航次	站位	孔号	岩心标号	段/cm	样品号	斑晶/微晶	点数		Na₂O	MgO	Al₂O₃	SiO₂	Cr₂O₃	MnO	FeO^T	K₂O	NiO	CaO	TiO₂	Total	An	Ab	Or
334	U1381	A	14	136~139	1381A-14R2	斑晶	12	AVE	1.45	0.23	34.40	46.95	0.01	0.01	0.46	0.02	0.01	17.70	0.03	101.26	86.97	12.90	0.12
						斑晶	12	STD	0.212	0.045	0.562	0.608	0.008	0.013	0.025	0.011	0.010	0.432	0.017	0.385	1.933	1.899	0.063
						微晶	7	AVE	3.48	0.29	30.59	50.72	0.01	0.01	0.74	0.07	0.02	13.92	0.06	99.92	68.56	31.02	0.41
						微晶	7	STD	0.577	0.045	1.029	1.213	0.009	0.019	0.211	0.026	0.020	0.964	0.036	1.486	5.044	4.908	0.153
	U1381	A	16	134~137	1381A-16R2	斑晶	11	AVE	3.43	0.15	31.09	50.13	0.01	0.02	0.37	0.07	0.01	14.08	0.06	99.42	69.28	30.32	0.40
						斑晶	11	STD	0.702	0.052	1.172	1.619	0.004	0.018	0.205	0.040	0.025	1.315	0.050	0.744	6.409	6.196	0.234
						微晶	7	AVE	5.19	0.16	28.05	53.91	0.00	0.02	0.73	0.12	0.02	11.03	0.09	99.32	53.63	45.67	0.70
						微晶	7	STD	0.702	0.052	1.172	1.619	0.004	0.018	0.205	0.040	0.025	1.315	0.050	0.744	6.409	6.196	0.234
	U1381	A	18	1~4	1381A-18R2	微晶	5	AVE	4.28	0.17	29.30	51.90	0.02	0.02	0.41	0.09	0.00	12.44	0.07	98.71	61.42	38.07	0.51
	U1381	A	18	1~4	1381A-18R2	微晶	5	STD	0.700	0.062	0.814	1.361	0.015	0.038	0.195	0.022	0.008	0.946	0.020	0.774	5.684	5.597	0.120
	U1381	A	20	115~118	1381A-20R2	微晶	11	AVE	4.89	0.12	28.47	54.16	0.01	0.01	0.54	0.11	0.01	11.31	0.07	99.71	55.69	43.66	0.65
	U1381	A	20	115~118	1381A-20R2	微晶	11	STD	0.840	0.059	1.523	2.690	0.009	0.012	0.179	0.052	0.011	1.708	0.035	1.304	8.101	7.793	0.315
	U1381	A	26	80~83	1381A-26R1	斑晶	5	AVE	2.03	0.21	32.97	46.93	0.01	0.03	0.33	0.05	0.01	16.31	0.02	98.89	81.40	18.33	0.27
						斑晶	5	STD	0.788	0.036	1.497	2.082	0.011	0.018	0.124	0.019	0.020	1.460	0.024	0.211	7.253	7.148	0.113
						微晶	5	AVE	4.60	0.18	28.88	52.82	0.01	0.02	0.67	0.12	0.00	12.01	0.09	99.42	58.59	40.68	0.73
						微晶	5	STD	0.328	0.042	0.878	0.782	0.017	0.036	0.236	0.030	0.006	0.771	0.048	0.933	3.307	3.172	0.177
344	U1381	C	13	11~16	1381C-13X1	斑晶	18	AVE	2.00	0.26	33.26	47.78	0.02	0.01	0.43	0.03	0.00	16.59	0.03	100.42	81.92	17.89	0.20
						斑晶	18	STD	0.686	0.036	1.335	1.500	0.016	0.019	0.102	0.019	0.008	1.329	0.023	1.159	6.316	6.215	0.114
						微晶	8	AVE	3.79	0.26	30.01	51.73	0.02	0.04	0.61	0.09	0.01	13.30	0.07	99.92	65.66	33.83	0.51
						微晶	8	STD	0.587	0.060	0.969	0.974	0.028	0.038	0.193	0.029	0.016	1.086	0.045	1.465	5.336	5.202	0.173
注：FeO^T为以FeO表示全铁含量；AVE表示平均值，STD表示标准偏差。

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表 2 典型斜长石斑晶电子探针分析组分(wt%)

Tab. 2 EPMA compositions (in wt %) of typical plagioclase phenocrysts

矿物号	位置	Na₂O	MgO	Al₂O₃	SiO₂	Cr₂O₃	MnO	FeO^T	K₂O	NiO	CaO	TiO₂	Total	An	Ab	Or	种属
1381A-14R2-pl-04	1	1.80	0.31	33.44	47.61	0.02	0.00	0.51	0.03	0.02	17.12	0.04	100.89	83.89	15.92	0.18	培长石
	2	1.71	0.32	33.92	48.13	0.00	0.01	0.44	0.03	0.01	17.00	0.04	101.61	84.42	15.39	0.18	培长石
	3	1.87	0.26	33.14	47.91	0.01	0.00	0.47	0.03	0.00	16.85	0.03	100.56	83.15	16.70	0.15	培长石
	4	1.29	0.23	34.47	46.47	0.01	0.00	0.47	0.00	0.02	17.96	0.00	100.92	88.48	11.51	0.01	培长石
	5	1.47	0.19	34.65	47.18	0.01	0.00	0.46	0.03	0.00	17.71	0.02	101.74	86.75	13.06	0.18	培长石
	6	1.37	0.25	34.43	46.94	0.02	0.00	0.42	0.02	0.02	17.70	0.04	101.21	87.62	12.27	0.11	培长石
1381A-16R2-pl-01	1	3.67	0.24	30.67	50.31	0.00	0.00	0.41	0.05	0.02	13.54	0.09	99.01	66.90	32.80	0.29	拉长石
	2	5.17	0.12	28.67	53.92	0.00	0.00	0.38	0.12	0.03	11.11	0.12	99.63	53.93	45.40	0.67	拉长石
	3	6.59	0.09	26.20	56.75	0.00	0.00	0.31	0.18	0.02	8.87	0.11	99.11	42.24	56.76	1.00	中长石
1381C-13X1-pl-01	1	1.82	0.25	33.87	47.16	0.04	0.01	0.46	0.04	0.03	17.43	0.02	101.11	83.95	15.84	0.21	培长石
	2	1.67	0.26	33.91	47.61	0.01	0.01	0.54	0.02	0.00	17.42	0.01	101.47	85.12	14.76	0.12	培长石
	3	1.82	0.23	34.04	47.65	0.03	0.03	0.47	0.02	0.00	17.02	0.04	101.34	83.69	16.20	0.11	培长石
	4	1.58	0.25	33.97	47.02	0.00	0.00	0.59	0.03	0.00	17.59	0.06	101.09	85.87	13.96	0.16	培长石
	5	1.54	0.22	34.05	46.83	0.01	0.01	0.57	0.02	0.00	17.45	0.01	100.72	86.15	13.75	0.10	培长石
	6	2.57	0.35	32.03	49.50	0.04	0.00	0.53	0.05	0.00	15.48	0.05	100.61	76.63	23.05	0.31	培长石
1381C-13X1-pl-06	1	1.49	0.27	34.01	45.40	0.04	0.00	0.19	0.04	0.00	17.20	0.00	98.63	86.28	13.49	0.23	培长石
	2	1.45	0.22	33.98	45.00	0.02	0.00	0.29	0.02	0.01	17.05	0.09	98.12	86.53	13.35	0.11	培长石
	3	3.25	0.26	30.93	49.14	0.00	0.00	0.37	0.05	0.00	14.40	0.01	98.40	70.79	28.93	0.28	培长石
注：FeO^T为以FeO表示全铁含量。“位置”列数字对应的测试点位置见图2。

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表 3 斜长石特征微量元素含量(10⁻⁶)

Tab. 3 Representative trace elements contents (10⁻⁶) of plagioclases

航次	站位	孔号	岩心标号	段/cm	样品号	测点号	斑晶/微晶	位置	An	La	Ce	Pr	Nd	Sm	Eu	Gd	Tb	Dy	Ho	Er	Tm	Yb	Lu
334	U1381	A	14	136~139	1381A-14R2	1381A-14R2-pl-04-1	斑晶	核	83.89	0.369	0.682	0.070	0.403	0.031	0.170	0.057	0.005	0.034	0.006	0.013	0.001	0.017	0.003
						1381A-14R2-pl-04-2	斑晶	核	84.42	0.317	0.566	0.063	0.301	0.056	0.158	0.043	0.003	0.019	0.005	0.007	0.004	0.013	0.003
						1381A-14R2-pl-04-3	斑晶	幔	83.15	0.360	0.720	0.085	0.432	0.047	0.140	0.064	0.007	0.044	0.006	0.026	0.004	0.012	0.002
						1381A-14R2-pl-04-4	斑晶	幔	88.48	0.320	0.647	0.066	0.328	0.041	0.167	0.042	0.003	0.032	0.006	0.013	0.004	0.008	0.003
						1381A-14R2-pl-04-5	斑晶	边	86.75	0.282	0.522	0.050	0.335	0.029	0.157	0.034	0.005	0.024	0.002	0.026	0.004	0.009	0.002
						1381A-14R2-pl-04-6	斑晶	边	87.62	0.246	0.472	0.058	0.283	0.029	0.171	0.033	0.003	0.020	0.005	0.012	0.003	0.012	0.002
						1381A-14R2-pl-07	微晶		71.21	0.737	1.393	0.180	0.888	0.209	0.277	0.224	0.044	0.318	0.072	0.209	0.027	0.229	0.035
						1381A-14R2-pl-08	微晶		62.81	4.990	11.880	1.509	8.130	1.885	0.758	2.606	0.413	2.930	0.649	2.389	0.269	1.796	0.267
						1381A-14R2-pl-09	微晶		76.18	19.350	44.740	5.850	31.170	7.740	2.490	9.830	1.575	10.980	2.328	6.910	0.979	6.320	0.965
	U1381	A	20	115~118	1381A-20R2	1381A-20R2-pl-07	微晶		45.73	0.649	1.193	0.122	0.669	0.106	0.991	0.078	0.012	0.070	0.014	0.054	0.010	0.066	0.007
						1381A-20R2-pl-09	微晶		40.82	0.862	1.489	0.148	0.821	0.046	2.073	0.032	0.012	0.034	0.004	0.011	0.003	0.012	0.002
						1381A-20R2-pl-11	微晶		52.29	0.556	1.028	0.115	0.605	0.082	0.512	0.044	0.007	0.030	0.004	0.044	0.004	0.014	0.004
						1381A-20R2-pl-10	微晶		63.90	0.457	0.823	0.092	0.541	0.120	0.409	0.066	0.005	0.047	0.008	0.018	0.002	0.013	0.004
344	U1381	C	13	11~16	1381C-13X1	1381C-13X1-pl-01-1	斑晶	核	83.95	0.307	0.666	0.071	0.380	0.045	0.172	0.048	0.009	0.039	0.009	0.018	0.003	0.014	0.002
						1381C-13X1-pl-01-2	斑晶	核	85.12	0.315	0.525	0.063	0.308	0.073	0.167	0.053	0.007	0.022	0.006	0.015	0.004	0.014	0.004
						1381C-13X1-pl-01-3	斑晶	幔	83.69	0.293	0.515	0.077	0.323	0.055	0.190	0.024	0.005	0.025	0.009	0.018	0.003	0.008	0.004
						1381C-13X1-pl-01-4	斑晶	幔	85.87	0.261	0.615	0.070	0.340	0.032	0.177	0.048	0.005	0.042	0.003	0.011	0.003	0.015	0.003
						1381C-13X1-pl-01-5	斑晶	边	86.15	0.281	0.558	0.068	0.353	0.067	0.189	0.038	0.004	0.024	0.005	0.011	0.003	0.016	0.004
						1381C-13X1-pl-01-6	斑晶	边	76.63	0.288	0.608	0.061	0.330	0.036	0.151	0.047	0.006	0.016	0.006	0.017	0.004	0.011	0.003
						1381C-13X1-pl-14	微晶		73.53	2.987	6.830	0.913	4.500	0.897	0.594	0.909	0.161	1.080	0.199	0.561	0.083	0.469	0.063
						1381C-13X1-pl-12	微晶		69.12	0.454	0.780	0.092	0.480	0.059	0.220	0.076	0.011	0.048	0.014	0.012	0.002	0.016	0.005
						1381C-13X1-pl-15	微晶		68.47	0.391	0.660	0.065	0.367	0.085	0.173	0.048	0.006	0.030	0.003	0.012	0.003	0.012	0.005

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续表3
测点号	∑REE	LREE/HREE	δEu	(La/Yb)_N	Rb	Sr	Y	Zr	Nb	Cs	Ba	Hf	Ta	Pb	Th	U	LILEs	HFSEs	Nb/Ta	Zr/Hf
1381A-14R2-pl-04-1	1.86	12.72	12.18	14.75	0.152	97.000	0.162	0.400	0.010	0.027	12.270	0.011	0.004	0.058	0.001	0.001	109.51	0.59	2.46	35.09
1381A-14R2-pl-04-2	1.56	15.11	9.41	17.23	0.061	99.120	0.076	0.380	0.008	0.027	12.270	0.008	0.004	0.020	0.001	0.002	111.50	0.48	2.32	46.91
1381A-14R2-pl-04-3	1.95	10.86	7.81	21.27	0.176	99.400	0.181	0.370	0.038	0.027	12.580	0.011	0.003	0.044	0.004	0.002	112.23	0.61	14.28	35.24
1381A-14R2-pl-04-4	1.68	14.06	12.12	26.19	0.060	96.870	0.090	0.370	0.018	0.026	10.680	0.011	0.005	0.043	0.002	0.003	107.68	0.50	3.79	35.24
1381A-14R2-pl-04-5	1.48	12.94	15.07	20.82	0.058	96.730	0.100	0.350	0.014	0.022	15.730	0.007	0.003	0.059	0.002	0.001	112.60	0.48	5.35	48.61
1381A-14R2-pl-04-6	1.35	14.06	16.84	14.04	0.276	95.200	0.085	0.380	0.008	0.026	14.730	0.015	0.003	0.068	0.000	0.000	110.30	0.49	2.63	24.68
1381A-14R2-pl-07	4.84	3.18	3.88	2.19	3.490	107.740	1.883	11.210	0.596	0.031	38.450	0.254	0.033	0.257	0.024	0.024	149.97	14.02	18.23	44.13
1381A-14R2-pl-08	40.47	2.58	1.04	1.89	10.250	62.640	18.950	49.050	4.620	0.349	23.490	1.489	0.336	1.602	0.346	0.142	98.33	74.93	13.75	32.94
1381A-14R2-pl-09	151.23	2.79	0.87	2.08	5.340	101.560	71.290	109.130	20.760	0.109	44.380	3.029	1.114	1.420	1.537	0.516	152.81	207.38	18.64	36.03
1381A-20R2-pl-07	4.04	12.07	31.77	6.73	0.793	139.010	0.353	1.420	0.035	0.059	45.390	0.028	0.008	1.520	0.004	0.004	186.77	1.85	4.16	51.64
1381A-20R2-pl-09	5.55	49.20	155.65	50.92	0.346	157.240	0.127	0.770	0.009	0.024	100.990	0.013	0.005	0.235	0.003	0.003	258.83	0.93	2.09	61.60
1381A-20R2-pl-11	3.05	19.20	23.46	26.23	0.193	128.750	0.181	0.360	0.008	0.026	27.570	0.013	0.005	0.162	0.004	0.002	156.70	0.57	1.74	27.69
1381A-20R2-pl-10	2.61	14.95	12.74	24.07	0.277	120.840	0.185	0.390	0.011	0.027	22.530	0.008	0.004	0.173	0.004	0.003	143.85	0.61	2.52	48.15
1381C-13X1-pl-01-1	1.78	11.69	11.19	15.00	0.109	101.780	0.163	0.480	0.061	0.030	11.580	0.019	0.006	0.049	0.007	0.005	113.55	0.74	11.16	24.74
1381C-13X1-pl-01-2	1.58	11.65	7.81	15.39	0.070	98.270	0.128	0.450	0.015	0.029	10.850	0.015	0.006	0.029	0.005	0.004	109.25	0.62	2.35	29.80
1381C-13X1-pl-01-3	1.55	15.15	13.66	24.57	0.070	101.200	0.110	0.560	0.011	0.030	11.000	0.014	0.003	0.049	0.002	0.003	112.35	0.70	3.56	40.88
1381C-13X1-pl-01-4	1.62	11.56	13.79	11.51	0.394	100.130	0.104	0.470	0.027	0.030	11.180	0.021	0.005	0.084	0.003	0.002	111.82	0.63	5.96	22.27
1381C-13X1-pl-01-5	1.62	14.60	10.46	11.78	0.069	102.430	0.143	0.440	0.023	0.029	10.610	0.012	0.005	0.047	0.005	0.002	113.18	0.63	4.42	36.97
1381C-13X1-pl-01-6	1.58	13.64	11.23	17.47	0.196	101.000	0.125	0.520	0.023	0.027	11.790	0.014	0.004	0.144	0.004	0.003	113.16	0.69	5.28	36.11
1381C-13X1-pl-14	20.25	4.74	1.99	4.33	1.689	115.810	5.510	7.940	1.501	0.070	50.150	0.220	0.089	0.445	0.166	0.104	168.16	15.53	16.83	36.09
1381C-13X1-pl-12	2.27	11.28	10.00	19.04	0.197	103.420	0.249	0.430	0.045	0.024	18.490	0.011	0.007	0.139	0.004	0.002	122.27	0.75	6.91	38.05
1381C-13X1-pl-15	1.86	14.71	7.56	21.77	0.381	99.170	0.135	0.420	0.012	0.024	19.160	0.017	0.004	0.122	0.003	0.004	118.86	0.59	2.98	24.14
注：δEu、(La/Yb)_N为球粒陨石^[31]标准化计算的结果。

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表 4 斜长石结晶温度范围

Tab. 4 Crystallization temperatures of plagioclases

样品号	斑晶/微晶	测点数	温度/℃
样品号	斑晶/微晶	测点数	${P_{{{\rm{H}}_{\rm{2}}}{\rm{O}}}}$＝0.5×10⁸ Pa	${P_{{{\rm{H}}_{\rm{2}}}{\rm{O}}}}$＝1.0×10⁸ Pa
1381A-14R2	斑晶	12	957～1 044	1 114～1 194
1381A-14R2	微晶	7	866～887	1 037～1 055
1381A-16R2	斑晶	11	903～1 119	1 050～1 253
1381A-16R2	微晶	7	926～988	1 071～1 128
1381A-18R2	微晶	5	941～954	1 089～1 101
1381A-20R2	微晶	11	878～986	1 030～1 128
1381A-26R1	斑晶	5	939～1 067	1 090～1 209
1381A-26R1	微晶	5	943～952	1 094～1 102
1381C-13X1	斑晶	18	1 019～1 121	1 149～1 249
1381C-13X1	微晶	8	1 021～1 033	1 151～1 163
注：温度列加粗的数据为实际选用的数据。

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