Experimental study of mineral production in primodal solar nebula

1. 采用TSFZ法在fayalite - forsterite固溶体中生长Fa_<100>、Fa_<90>、Fa_<80>、Fa_<70>和Fa_<60>单晶。采用HCl 1N或NaOH 1N溶液，在300℃、0.1Kbar和HM缓冲液条件下，对厚度约为15 μ m的薄片（010）进行水热处理。在酸性条件下橄榄石沿（001）和碱性条件下沿（100）分别产生平面相。在酸性条件下由赤铁矿和无定形二氧化硅组成，在碱性条件下由赤铁矿和来铁矿组成。我用橄榄石在水氧化环境中阳离子浸出机理的改变来解释这些结果。这说明C球粒陨石在碱性氧化条件下发生了蚀变。我在日本矿物学学会年会上作了口头报告，并发表在《国际矿物物理化学杂志》上。在25mmHg条件下，冷凝温度为1150℃-1100℃，持续时间为10分钟，在a轴上伸长的韧化辉石晶须的作用实验很少，但可以肯定。在高于1150℃的温度下，没有晶须发生缩聚，在低于1100℃的温度下，只有C轴伸长的韧辉石晶须发生缩聚。在高过饱和（高温）条件下，由于晶体可以向任何方向生长，所以在a轴上拉长的能耐火辉石晶须可以以一定的概率生长。然而，只有在低过饱和度（低温）下才能生长出c轴伸长的韧辉石晶须，因为只有这些晶须才能在低温下生长出最高的晶体生长速率。另一方面，在本实验中产生的a轴伸长的猝灭辉石晶须中发现了倒孪晶。因此，这些顽辉石须须可能生长在原顽辉石稳定区内，而在行星际尘埃中发现的顽辉石须须是斜顽辉石，没有倒孪晶，必须在低温下亚稳态生长。少

1. Reproduction experiments of (100) plane defects in olivineSingle crystals of Fa_<100>, Fa_<90>, Fa_<80>, Fa_<70>, and Fa_<60> in Fayalit-Forsterite solid solition were grown by TSFZ method. Thin sections (010) of about 15 mum thickness were hydrothermally altered at condition of 300ﾟC,0.1Kbar and HM buffer using HCl 1N or NaOH 1N solution. Planar precipitates were produced along (001) or (100) of olivine in acidic condition or alkaline condition, respectively. Oriented precipitates complexes were composed of hematite and amorphous silica in acidic condition and hematite and laihunite in alkaline condition. I explaned these results by cation leaching mechanism during olivine is altered in aqueous oxidizing environment. This result means that C chondrite was altered in alkaline oxidizing condition. I gave oral presentaiton on these results at Annual Meeting of Mineralogical Society of Japan and published them in the International Journal of Physics and Chemistry of Minerals.2. Reprodu … More ction experiments of enstatite whiskers which are elongated in a-axisEnstatitet whiskers which are elongated in the crystallogaraphic a-axis were produced only a few, but surely, at 25mmHg, at condensation temperature of 1150 ﾟC-1100 ﾟC and in the duration time of 10 minutes. None was condensated at the temperature higher than 1150 ﾟC,and enstatite whiskers elongated in c-axis was condensated alone at lower temperature than 1100ﾟC.Enstatite whiskers elongated in a-axis can grow in some probability at high supersaturation (high temperature) because crystal can growth at any direction in these conditions. However, enstatite whiskers elongated only in c-axis grow at low supersaturation (low temperature), because only these whiskers which is the highest crystal growth rate at low temperature can grow. On the other hand, inverted twins were found in the enstatite whiskers elongated in a-axis produced in this experiment. Threfore, these enstatite whiskers might be grown in the protoenstatite stable region, while enstatite whiskers found in interplanetary dust are clinoenstatite without inverted twins, which must be grown metastably at low temperature. Less