發(fā)布時間：2018-11-16 20:30

【摘要】：為了解海底浮巖氣孔充填物對全巖微量元素組成的影響,并獲得有效的海底浮巖前處理方法,對沖繩海槽中部的浮巖碎成大于5 cm,1~2 cm及小于5 mm的碎塊分別進(jìn)行前處理,然后通過掃描電鏡(SEM)和X射線衍射光譜(XRD)分析對清洗的效果進(jìn)行觀察對比。結(jié)果表明,對大塊浮巖直接清洗以及將浮巖碎成厘米級小塊后清洗都難以將浮巖氣孔內(nèi)充填的細(xì)粒沉積物去除干凈,而對浮巖碎成毫米級(5 mm)顆粒后再清洗可以有效清除浮巖氣孔內(nèi)的充填物。本文所確定的一套有效的海底浮巖前處理方法總結(jié)如下:(1)將小于5 mm的浮巖顆粒置于超聲波清洗機(jī)內(nèi)用蒸餾水清洗,每隔15 min換一次水,直到清洗樣品后的水足夠清澈;(2)將樣品先后浸入無水乙醇和稀鹽酸溶液中,分別去除有機(jī)質(zhì)和次生碳酸鹽、鐵氧化物;(3)將浮巖樣品置于40℃超純水中浸泡7 d左右,并每天換水,直至向上層清液加硝酸銀溶液無白色沉淀出現(xiàn)。XRD分析表明,海底浮巖氣孔中充填物的礦物組成包括斜長石、石英等。少量的氣孔充填物對浮巖全巖的微量元素配分模式影響不大,但會造成Pb、Sr等元素含量的增加,因此可能會對浮巖全巖的Pb-Sr同位素組成造成干擾。
[Abstract]:In order to understand the effect of pore filling on the trace element composition of the whole rock, and to obtain an effective pretreatment method of submarine floatation rock, the fragmentation of the floating rock in the middle of Okinawa trough was pretreated for more than 5 cm,1~2 cm and less than 5 mm, respectively. Then the cleaning effect was observed and compared by scanning electron microscope (SEM) and X-ray diffraction (XRD). The results show that it is difficult to clean the fine sediment filled in the pore of the floatation rock directly and after the floatation rock is broken into centimeters. The filling material in the pore can be effectively removed after the floatation is broken into millimeter (5 mm) particles and then cleaned. A set of effective pre-treatment methods for submarine floatation are summarized as follows: (1) the floatation particles less than 5 mm are washed with distilled water in the ultrasonic cleaning machine, and the water is changed every 15 min until the water is clear enough after cleaning the sample; (2) the samples were immersed in anhydrous ethanol and dilute hydrochloric acid respectively to remove organic matter, secondary carbonate and iron oxide. (3) the floating rock samples were immersed in ultrapure water at 40 鈩，

本文編號：2336565