|
|
|
| THE MESOPROTEROZOIC KOMATIITES AND THEIR GENETIC TYPE IN THE JIFENG AREA OF DAXINGANLING |
| LI Yang-chun, ZHAO Hai-bin, YANG Xiao-ping, HAN Wei-min |
| Qiqihar Branch, Research Institute of Regional Geological Survey of Heilongjiang, Qiqihar 161005, China |
|
|
|
|
Abstract The peridotitic komatiites in Jifeng area of Daxinganling are with fine microspinifex texture.The matrix materials existing between olivine and augite crystals indicate a volcanic origin.Systematic research has initialy iden-tified a chill zone and a spinifex zone,which constitute an incomplete condensate unit.The petrochemical characteristics of the Jifeng komatiites are in accordance with the peridotitic komatiites in South Africa and Western Australia.The geochemistry study shows a close genetic relationship between the komatiites and the associated basalts,with a positive correlation,conforming to the evolutionary trend of komatiite-tholeiite.The cardinal elements,trace elements and REE of the komatiites in the area present a perfect attribute of type Ⅱ komatiite,which is compatible with the type Ⅱ komatiite in South Africa,India,and West Greenland.The Jifeng komatiites are characterized by low LREE affluence,withεNd (T)=+7.51,showing that the komatiites are derived from partially melted depleted mantle.The komatiites were formed in Mesoproterozoic,in atectonic environment of tensile crust,while the rising komatiite magma was quenched and rapidly cooled.The Jifeng komatiites provide a new key for research of Mesoprote rozoic tectonics in Daxinganling area.
|
|
Received: 11 December 2001
|
|
|
|
|
|
| [1] |
CHEN Hui-jun, CUI Tian-ri, QIAN Cheng, LI Lin-chuan, CHEN Jing-sheng, LI Wei, WU Xin-wei, JIANG Bin, SI Qiu-liang, QIN Tao, TANG Zhen, ZHANG Yu-jin, GUO Wei. ZIRCON U-Pb GEOCHRONOLOGY OF BASHENGHE PLUTON IN NORTHERN DAXINGANLING MOUNTAINS: Geological Implications[J]. GEOLOGY AND RESOURCES, 2019, 28(5): 405-412. |
|
|
|
|
2002, Vol. 11 
