@article{oai:nipr.repo.nii.ac.jp:00010200,
 author = {Takafumi, Niihara and Naoya, Imae and Keiji, Misawa and Hideyasu, Kojima and Takafumi, Niihara and Naoya, Imae and Keiji, Misawa and Hideyasu, Kojima},
 issue = {4},
 journal = {Polar science, Polar science},
 month = {Jan},
 note = {We studied the petrology and mineralogy of two types of shock-melted H chondrites: Yamato (Y)-791088 and LaPaz Ice Field (LAP) 02240. Y-791088, which consists of numerous coarse-grained relict phases (40%) and euhedral fine-grained minerals solidified from the shock melt (60%), experienced incomplete melting; a quiescent melt is indicated by the existence of abundant relict phases, pseudomorphed chondrules, and two types of glass. LAP 02240, which consists of small amounts of coarse-grained relict phases (10%) and fine-grained minerals (90%), experienced near-complete melting; a rapidly cooled mobilized melt is indicated by the homogeneous compositions of glass and opaque veins.The homogeneous compositions of relict olivines indicate that the precursors of both chondrites were equilibrated H chondrites. The melting features of Y-791088 and LAP 02240 are very similar to those of Y-790964 (LL) and the fine-grained lithology of Y-790519 (LL), respectively. These two types of shock-melted ordinary chondrites possibly formed in situ during dike formation. The quiescent melt is thought to have originated from the injection of shock-heated chondrite blocks into mobilized melt. These two types of melting could have occurred during dike formation on the H chondrite parent body. The textures of the two types of shock melts were not simply affected by the degree of shock melting: they were also controlled by the degree of shear stress., 異なる特徴を持つHコンドライトの衝撃溶融岩（Y-791088およびLAP 02240）を、岩石・鉱物学的視点から比較し、形成環境を検討した。Y-791088は，とけ残り物質を約40％含み，コンドルールの形態を保持している。一方、LAP 02240は約10％のとけ残り物質を含み、コンドルールは変形している。同様の特徴はLLコンドライトの衝撃溶融岩である、Y-790964およびY-790519で観察される。Y-790519では、２つの衝撃溶融岩相が共存しており、両岩相が同時に形成したことを示している。異なる衝撃溶融岩の特徴は、溶融度の違いのみではなく、加わった剪断応力の差を反映していると考えられる。},
 pages = {558--573},
 title = {Petrology and mineralogy of the shock-melted H chondrites Yamato-791088 and LaPaz Ice Field 02240},
 volume = {4},
 year = {2011}
}