Study of sclerochronology by laser ablation ICP-MS
Study of sclerochronology by laser ablation ICP-MS
复制标题
通过激光烧蚀 ICP-MS 进行硬化年代学研究
DOI：
10.1039/b002014l
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
M. Leng
中科院分区：
文献类型：
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作者：
H. Toland;Bill Perkins;N. Pearce;Fergus Keenan;M. Leng
岩石年代学之于贝壳，就像树木年代学之于树木一样，也就是说，某些贝壳（在本例中是双壳软体动物Arctica islandica L., Ocean Quahoc）的生长结构在形式和内容上类似于树木的生长结构，它们每年都有周期性的生长。利用激光烧蚀电感耦合等离子体质谱（LA-ICP-MS），结合稳定同位素分析对贝壳内的生长结构进行取样，可以确定贝壳形成时普遍存在的环境条件（例如环境温度、盐度、季节性和生产力）。从诸如此类的生物碳酸盐中提取任何数据的一个限制因素是从中提取信息的重复生长结构的大小。在北极地区，这些误差可以低至几十微米。微钻井技术，如同位素分析中常用的技术，受到用于收集样品的钻头尺寸的限制。LA-ICP-MS具有超高空间分辨率（10-20µm烧蚀坑）和精度，可提供高度受限的分析，允许对贝壳内季节性生长带进行精确的多元素采样。使用锶、镁和钡元素作为年际环境条件的记录可能是可行的，从而在某些情况下不需要进行稳定同位素分析，特别是在要取样的材料的大小需要LA-ICP-MS的高分辨率的情况下。
Sclerochronology is to shells what dendrochronology is to trees, i.e., growth structures within some shells (in this case the bivalve mollusc Arctica islandica L., the Ocean Quahoc) resemble, in form and content, those growth structures in trees, which grow with an annual periodicity. By utilising laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), allied with stable isotope analysis to sample the growth structures within shells, environmental conditions (e.g., ambient temperature, salinity, seasonality and productivity) prevalent at the time of shell genesis may be ascertained. A limiting factor in the retrieval of any data from biogenic carbonates such as these is the size of the repeated growth structures from which to extract information. In the case of Arctica, these can be as low as tens of µm. Micro-drilling techniques, such as those commonly used in isotope analyses, are constrained by the size of the drill bit used to collect the sample. LA-ICP-MS, with its ultra-high spatial resolution (10–20 µm ablation pits) and precision, delivers highly constrained analysis allowing accurate multi-element sampling of seasonal growth bands within shells. It may be feasible to use the elements strontium, magnesium and barium as records of inter-annual environmental conditions, thus removing the need to carry out stable isotope analyses in some instances, particularly where the size of the material to be sampled demands the high resolution of LA-ICP-MS.