Five silica‐rich objects (SRO) from Acfer 182 were studied. They have cryptocrystalline textures characterized by micro‐emulsion and amoeboid patterns that point toward the coexistence of pyroxene‐ and silica‐normative liquids that were quenched. Both objects have variable contents of refractory lithophile elements. Their positive Yb versus La correlation around primordial values suggests a cosmochemical process (e.g., a gas/liquid condensation) as responsible for SRO formation. The bulk trace element abundances of amoeboid‐ and emulsion‐type SRO as well as their fractionation do not support an origin through high temperature processes. Conversely, their formation might have taken place while cooling of the nebular gas in two different chondrule‐forming regions characterized by having different evolution paths. Cooling of these dust‐enriched regions might lead to the condensation of pyroxene‐rich liquids first, followed by formation of Mg‐rich and SiO₂‐rich liquids, provided irradiation and annealing were active in these regions. Irradiation could be the process involved both in the formation of cristobalite (with annealing ~1200 K) and in triggering a spinoidal decomposition causing unmixing of the enstatite liquid into two coexisting phases, such as Mg‐rich and SiO₂‐rich liquids, the precursors of the SRO in Acfer 182. Formation of emulsion‐ and amoeboid‐type objects may be the result of exposing those chondrule‐forming regions to different degrees of radiation.

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Acfer 182 CH球粒陨石中富含二氧化硅的物体：新视图

研究了来自Acfer 182的五个富含二氧化硅的物体（SRO）。它们具有隐晶质感，其特征在于微乳状液和变形虫图案，这表明被淬火的辉石和二氧化硅规范液体共存。这两个物体的耐火亲石元素含量均变化。它们在原始值附近的正Yb与La相关性表明，宇宙化学过程（例如，气体/液体冷凝）是SRO形成的原因。变形虫和乳液型SRO的大量痕量元素丰度及其分馏不支持通过高温过程产生。相反，它们的形成可能是在两个以不同的演化路径为特征的不同的软骨形成区域中，对星状气体进行冷却时发生的。如果在这些区域中进行辐照和退火，则富含_2种液体。辐照过程可能涉及方石英的形成（退火至〜1200 K）以及引发纺锤状分解，从而导致顽辉石液体分解为两个共存相，例如富Mg和SiO ₂富液（前体）这是Acfer 182中SRO的结果。形成乳剂和类阿波美类物体的原因可能是使那些形成软骨的区域受到不同程度的辐射。