<正>An extensive survey of dykes in the Valles Marineris troughs(chasmata)on Mars has been undertaken.Most dykes are observed along the chasma walls(Mège a
The Langdu high-K calc-alkaline intrusions are located in the Zhongdian area, which is the southern part of the Yidun island arc. These intrusive rocks consist
<正>1 Introduction The howardite,eucrite and diogenite(HED)meteorites are ultramafic and mafic igneous rocks and impact-engendered breccias derived from a thoro