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在没有经过热液活动的希拉(Gila)砾岩层的上新世或更新世湖成相沸石凝灰岩中有20—30%的萤石。浅灰色沸石凝灰岩厚约40cm,在新墨西哥巴克霍恩东部约2.5Km处出露面积约为0.6Km~2。凝灰岩被含有大量醒目的马加迪(Magadi)型燧石的沸石泥岩所覆盖,萤石呈扁长的球粒产出,极少部分呈0.1—0.3mm的(?)粒状产出,很少有破碎的球粒和(?)粒。X光衍射和扫描电镜研究表明,球粒和(?)粒主要是由超微粒的萤石和石英组成。这两种矿物都无固定的形态。这些球粒和(?)粒嵌入基质。基质主要由亚显微粒状的发光沸石和蒙脱石组成并具有不明显的玻屑状结构。由于泉水或河流中稀释的含钙质的水与含高氟的盐碱性湖水混合,导致萤石和麦羟硅钠石原生沉淀而形成球粒和(?)粒。然后球粒和(?)粒被搬运到盆地并与再沉积的富玻璃质火山灰混合.在成岩过程中,球粒状和(?)粒状的麦羟硅钠石转变成石英,火山灰中的玻璃蚀变成发光沸石和蒙脱石。
There are 20-30% fluorite in the Pliocene or Pleistocene lacustrine tuff, which has not been hydrothermally active in the Gila conglomerate. The light gray zeolite tufa is about 40 cm thick, with an area of about 0.6 km 2 exposed at about 2.5 km east of Barkhorn, New Mexico. Tuff is covered by zeolite mudstone containing a large number of prominent Magadi type flint. Fluorite has prolate spherulites and very few (-0.3 mm) granular forms, rarely crushed Pellets and (?) Tablets. X-ray diffraction and scanning electron microscopy studies show that the pellets and (?) Grains are mainly composed of ultrafine particles of fluorite and quartz. Both minerals have no fixed form. These pellets and (?) Particles embedded in the matrix. The matrix consists mainly of sub-micronized mordenite and smectite and has an insignificant glass-like structure. Because of the dilution of calcium-containing water in springs or rivers with high-salt, saline-alkaline lakes, fluorite and quarzalite are initially precipitated to form pellets and granules. The pellets and (?) Pellets are then transported to the basin and mixed with the redeposited vitravasitic volcanic ash, during which the pelleted and (?) Granular magadiite convert to quartz and the glass in volcanic ash Become mordenite and montmorillonite.