论文部分内容阅读
南极乔治王岛化石山剖面的化石山组主要由沉积火山碎屑岩（包括沉火山角砾岩和沉凝灰岩）组成，上部夹正常沉积岩和两层薄煤层，形成从粗到细的两个沉积旋回。第１旋回的沉火山角砾岩和沉凝灰岩由不同粒级的火山岩岩屑、斜长石晶屑和细火山尘基质组成，火山碎屑物质含量在９０％以上，沉积特征显示从火山碎屑流（？）到低密度流的快速堆积性质。其中第１、２层沉凝灰岩受强烈的沸石化（浊沸石和方沸石）作用，而泥级沉凝灰岩夹层的细火山尘物质多已变成绿泥石－蒙脱石规则混层矿物；因为这种混层矿物也常常被沸石化，故其形成应在沸石化作用之前。Ｘ－衍射分析显示较多钠长石的存在。钠长石和方沸石的钠可能来自中长石被浊沸石化后释放出的Ｎａ＋。第２旋回由沉火山角砾岩、沉凝灰岩夹岩屑长石杂砂岩和薄煤层组成，显示正常沉积物经常被携入沉积盆地。第３、４层的泥级沉凝灰岩以显著的蒙皂石化为特征，沸石化作用不发育；其中的斜长石主要是中长石和（或）拉长石。化石山组泥级沉凝灰岩的微量元素组分及含量与下伏玛瑙滩组顶部安山岩的相当，但第２～３层间有某些元素迁移和富集，这可能与层间热水溶液的活动有关。Ｂ含量特别低（＜１×１０－６），不仅指示背景值低，而且也说明沉积环境与海水没有关?
The Fossil Mountains Formation in the section of the fossil mountain of King George Island in the Antarctic consists mainly of sedimentary volcaniclastic rocks (including the volcanic breccias and tuffaceous limestone) with normal sedimentary rocks and two thin seams on the upper part, forming two sediments from coarse to fine Swing. The volcanic rock fragments, plagioclase quartzites and fine volcanic ash matrix composed of volcanic rocks, volcanic clastic material, and volcaniclastic matter are all over 90%. The sedimentary characteristics show that volcanic clastic Rapid packing of stream (?) To low density stream. The first and second layers of tuff are strongly zeolitized (laumontite and analcime), and fine volcanic dusts in the intercalated layers of tuff-tuff have been converted into chlorite-montmorillonite mixed minerals. Because This mixed mineral is also often zeolitic, so its formation should be before the zeolitization. X-ray diffraction analysis shows the presence of more albite. Sodium of feldspar and analcime may come from the Na + released after the mesophase is turbid-zeolitized. The second cycle is composed of volcanic breccia, sedimentary tuff feldspar feldspathic sandstone and thin coal seams, indicating that normal sediments are often carried into the sedimentary basin. Mud-grade tuffaceous limestone in the third and fourth layers is characterized by a significant smectite and zeolite is undeveloped. The plagioclase is mainly feldspar and / or labradorite. The trace element composition and content of the mud-graded tuff in the Huoshishan Formation are similar to that of the andesite at the top of the next Onyaotan Formation, but some elements migrate and enrich in the second to third layers, which may be related to the activity of the inter-layer hot-water solution related. B content is particularly low (<1 × 10-6), not only indicates that the background value is low, but also shows that the sedimentary environment and sea water is not related?