海底浮岩前处理方法的实验研究
Experimental study of a pretreatment method for submarine pumice
摘要
Abstract
This study was conducted to analyze the influences of sediment infillings in submarine pumice's vesicles on whole-rock trace element compositions of pumice and to identify an effective pretreatment method for subma-rine pumice. The pumice obtained from the middle Okinawa Trough was pretreated after breaking it into fragments of sizes >5 cm, 1~2 cm, and <5 mm. Scanning electron microscope (SEM) and X-ray diffraction (XRD) analyses were conducted to observe and compare the cleaning results. Experimental results showed that direct cleaning by large pumice fragments or cleaning after the pumice was broken into centimeter-scale fragments failed to remove completely the fine-grained sediments filled in the vesicles of the pumice. However, cleaning after the pumice was crushed into millimeter-scale fragments could effectively clean up the vesicles of the pumice. This study summa-rized an effective pretreatment method for submarine pumice as follows: (1) clean the pumice fragments (<5 mm) using distilled water in an ultrasonic bath and change the water every 15 min until the water after cleaning the samples becomes clear enough, (2) place the fragments in anhydrous ethanol and dilute hydrochloric acid solution (0.5 mol/L) to remove organic matter and secondary carbonate and Fe oxides, respectively, and (3) place the pumice fragments in ultrapure water at 40℃ for about 7 days, with water being changed every day until the removal of chloridion. The results of SEM and XRD analyses showed that the mineral composition of the fillings in the submarine pum-ice's vesicles includes plagioclase and quartz. Small amount of vesicle fillings has mild effects on the whole-rock trace element distribution pattern of pumice. However, the fillings could increase the contents of Pb and Sr and, thus, might disturb the whole-rock Pb and Sr isotopic compositions of pumice.关键词
海底浮岩/前处理/气孔充填物/微量元素Key words
submarine pumice/pretreatment/vesicle fillings/trace elements分类
海洋科学引用本文复制引用
张玉祥,曾志刚,殷学博,齐海燕,李禾,王晓媛,陈帅..海底浮岩前处理方法的实验研究[J].海洋科学,2017,41(7):64-70,7.基金项目
国家重点基础研究发展计划(2013CB429700) （2013CB429700）
国家自然科学基金(41325021, 41306053, 41476044) （41325021, 41306053, 41476044）
中国科学院战略先导专项(XDA11030302) （XDA11030302）
山东省泰山学者专项基金 （）
中国科学院、国家外国专家局创新团队国际合作伙伴计划 （）
青岛海洋科学与技术国家实验室鳌山人才计划 （）
鳌山科技创新计划项目(2015ASKJ03, 2016ASKJ13) The National Key Basic Research Program of China, No. 2013CB429700 （2015ASKJ03, 2016ASKJ13）
National Science Foundation of China, No. 41325021, No.41306053, No.41476044 （）
Strategic Priority Research Program of the Chinese Academy of Sciences, No. XDA11030302 （）
the Special Fund for the Taishan Scholar Program of Shandong Province （）
the CAS/SAFEA International Partnership Program for Creative Research Teams （）
the Aoshan Talent Program of Qingdao National Laboratory for Marine Sci-ence and Technology （）
the Aoshan Science and Technology Innovation Program, No. 2015ASKJ03, No. 2016ASKJ13 （）
