Trace Element Partitioning in Immiscible Silicate–Carbonate Liquid Systems: an Initial Experimental Study Using a Centrifuge Autoclave
Trace Element Partitioning in Immiscible Silicate–Carbonate Liquid Systems: an Initial Experimental Study Using a Centrifuge Autoclave
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DOI：
10.1093/petroj/39.11-12.2095
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发表时间：
1998-11
影响因子：
3.9
通讯作者：
I. Veksler;C. M. Petibon;G. Jenner;A. Dorfman;Donald Bruce Dingwell
中科院分区：
文献类型：
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作者：
I. Veksler;C. M. Petibon;G. Jenner;A. Dorfman;Donald Bruce Dingwell
碳酸盐的起源仍然是一个有争议的话题。硅酸盐和硅酸盐-碳酸盐之间的液体不混相一直是碳酸盐液体不混相的重要因素。为了理解并提出限制这一过程可能的成因机制，在微量元素分配数据中有与超镁质碱性岩相关的碳酸盐岩是很重要的。对复合火山和次火山杂岩的实验研究较少。在硅酸盐和碳酸盐液体之间进行微量元素分配的实地观察（Ferguson & Currie, 1971； Kjarsgaard &已经进行，反映了分析和实验Peterson, 1991; Church & Jones, 1995）和有关困难的数据。为了实现更好的相分离，矿物中新的双液熔体包裹体（Rankin & Le Bas, 1974；利用旋转离心机Romanchev & Sokolov， 1979）支持液体高压灭菌器的作用。用原位不混相法分析了碳酸盐岩成岩过程中生成产物中的微量元素。自从Koster van Groos & Wyllie（1963）光谱法应用激光烧蚀微探针-电感耦合等离子体质量工程以来。已经确定了从稀土元素（La, Nd, Sm, Tb, Er, Tm）中分离出碳酸盐不混相液体的分配系数(D)，高场碳酸化硅酸盐熔体中发现了延伸元素（Zr, Hf, Nb, Ta）以及Sr， Ba和y。大多数实验表明，在许多合成硅酸盐-碳酸盐体系中，稀土元素优先分配到硅酸盐和天然岩石成分中[例如，见液体综述]。然而，La、Sr和Ba强烈地划分为碳酸盐[Kjarsgaard & Hamilton(1989)]。然而，没有液体。高场强元素的特点是碳酸盐岩岩浆的广泛发育（见Gittins， 1989），尽管人们对液体不混溶在硅酸盐液体中所起的作用都有优先的共识。D值的范围。Zr和Hf具有相似的D值，在此基础上，定量实验数据比Nb、Ta和微量元素在不混相液体Ti之间分配的结果低一到两个数量级。Ti和Nb的行为相似，而Ta的行为对限制碳酸盐的起源很重要。Zr和Hf的中间产物。Nb/Ta比值对硅酸-碳酸盐体系的实验研究具有很强的分馏作用。受快速结晶的阻碍，碳酸盐丰富
The origin of carbonatites remains a contentious topic. However, INTRODUCTION an important role for liquid immiscibility between silicate and Silicate–carbonate liquid immiscibility has often been carbonate liquids has often been proposed. To understand and proposed as a possible mechanism for the origin of constrain the role this process may play, it is important to have carbonatites associated with ultramafic alkaline rocks in trace element partitioning data available. Few experimental studies composite volcanic and subvolcanic complexes. Field on trace element partitioning between silicate and carbonate liquids observations (Ferguson & Currie, 1971; Kjarsgaard & have been undertaken, reflecting both analytical and experimental Peterson, 1991; Church & Jones, 1995) and data on difficulties. To achieve better phase separation new two-liquid melt inclusions in minerals (Rankin & Le Bas, 1974; experiments have been performed utilizing the rotating centrifuge Romanchev & Sokolov, 1979) support the role of liquid autoclave. Trace elements in the run products were analysed in situ immiscibility in carbonatite petrogenesis. Since the piusing laser ablation microprobe–inductively coupled plasma mass oneering work of Koster van Groos & Wyllie (1963) spectrometry. Partition coefficients (D) have been determined for the separation of carbonatitic immiscible liquids from selected rare earth elements (La, Nd, Sm, Tb, Er, Tm), high field carbonated silicate melts has been demonstrated exstrength elements (Zr, Hf, Nb, Ta), and for Sr, Ba and Y. Most perimentally in many synthetic silicate–carbonate systems of the rare earth elements partition preferentially into the silicate and for natural rock compositions [e.g. see review by liquid. La, Sr and Ba, however, strongly partition into the carbonate Kjarsgaard & Hamilton (1989)]. However, there is no liquid. The high field strength elements, although all preferentially consensus about the role of liquid immiscibility in the partitioning into the silicate liquid, are characterized by a wide development of carbonatite magmas (see Gittins, 1989). range of D values. Zr and Hf have similar D values, which are In this connection, quantitative experimental data on one to two orders of magnitude lower than those of Nb, Ta and trace element partitioning between the immiscible liquids Ti. Ti and Nb behave similarly, whereas Ta demonstrates behaviour are important for constraining the origin of carbonatites. intermediate to that of Zr and Hf. Nb/Ta ratios are strongly Experimental studies in silicate–carbonate systems are fractionated by two-liquid partitioning. hampered by the rapid crystallization of carbonate-rich