Trace analysis of hydrocarbons in Porites coral cores from the Arabian Gulf, Saudi Arabia

Short coral cores were collected from 28 Porites coral colonies at four reef sites (Jurayd, Jana, Karan and Gosp-4) in the Arabian Gulf in January-February 2003. The coral cores were mounted, sliced and X-rayed to reveal annual density banding patterns. Fifteen of the 28 cores were sufficiently intact for accurate identification of year bands and chemical analysis.Samples were cut from one or two slices of each core down to the earliest year band. Samples chosen for analysis included the 1991 and where possible, the 1983 year bands. Samples were then cut into year-bands and pieces of coral belonging to one year band were placed into separate solvent cleaned 20ml glass vials.After extraction using dichloromethane and sonication and being passed through a column containing sodium sulphate, samples were scanned by ultraviolet fluorescence spectroscopy (UVF) and were then analysed using gas chromotography and mass spectroscopy detection (GCMS). The purpose of this research was to conduct a study of hydrocarbon biomarkers in corals as part of an assessment of the impact of the 1991 oil spill on Arabian Gulf coral reefs. Growth data derived from these cores are described in the metadata record "Growth records in Porites coral cores from the Arabian Gulf, Saudi Arabia"

2003年1—2月，研究人员于阿拉伯湾（Arabian Gulf）的4处珊瑚礁站位（朱赖德Jurayd、贾纳Jana、卡兰Karan、戈斯普-4 Gosp-4）的28个滨珊瑚（Porites）群落中采集了短柱状珊瑚岩心。将采集得到的珊瑚岩心进行封装、切片并开展X射线扫描，以显现其年度密度条带结构。28份岩心中共有15份保存完好，可准确识别年生长纹并开展化学分析。从每份岩心的1或2个切片中截取样本，直至最早期的年生长纹，本次选取的分析样本包含1991年的珊瑚组织，若样本条件允许则同时纳入1983年的珊瑚组织。随后将样本按年生长纹进行切割，对应同一年生长纹的珊瑚组织被分别装入经溶剂清洗后的20mL玻璃小瓶中。经二氯甲烷萃取、超声处理，并通过装填硫酸钠的层析柱净化后，研究人员采用紫外荧光光谱法（ultraviolet fluorescence spectroscopy, UVF）对样本进行扫描，随后通过气相色谱-质谱联用法（gas chromatography and mass spectrometry detection, GCMS）完成分析。本研究旨在分析珊瑚体内的烃类生物标志物，以此作为评估1991年石油泄漏对阿拉伯湾珊瑚礁影响的研究内容之一。从这批岩心中提取的生长数据已在元数据记录《沙特阿拉伯阿拉伯湾滨珊瑚岩心生长记录》中予以详细说明。