Petrology and Geochemistry of Ultramafic Rocks in the Yishui Complex , Shandong
详细信息
- 责任者：Zhao Ziran (Institute of Geology ; Chinese Academy of Geological Sciences ; Beijing 100037 ; China) ; Song Huixia
- 刊名：Acta Petrologica et Mineralogica
- 出版年：2011
- 卷期：30(5)
- 关键词：超镁铁质岩 ; ultramafics ; 山东 ; Shandong Province
- 页码：p.853-864
- 图表：7 illus., 2 tables, 20 refs.
- 分类号：0801
- issnNo：ISSN1000-6524
- isbnNo：CN11-1966/P
摘要
Summary name="EnDivSummary">Ultramafic rocks occur mainly as inclusions or xenoliths in Yishui magmatic and metamorphic complexes,without typical spinifex texture.Their chemical compositions are characterized by high MgO(22.23%~27.49%,>20%) and low SiO2(38.60%~49.40%),TiO2(0.11%~0.39%,<0.5%) and K2O(0.02%~0.39%,<0.5%) content.As for other oxide compositions,total iron(FeOT) values are in the range of 7.68%~11.14%,CaO content ranges 5.15%~12.86%,and Al2O3 content varies remarkably in the range of 1.56%~8.94%.The CaO/Al2O3 ratios of most samples are 0.61~1.36(≈1),with the exception of three samples,whose CaO/Al2O3 ratios are 7.70~8.20(>1) and MgO/FeOT ratios are 2.00~3.33.MnO(0.13%~0.20%) and Na2O(0.12%~1.03%) content is low. In summary,the ultramafic rocks originated from the mantle,formed in the early Neoarchean,and were then subjected to anatexis and magmatic effects,thus experiencing metamorphic transformation.