scholarly journals Secular Evolution of Lithospheric Mantle Beneath the Central North China Craton: Implication from Basaltic Rocks and Their Xenoliths

10.5772/23074 ◽  
2012 ◽  
Author(s):  
Yan-Jie Tang ◽  
Hong-Fu Zhang ◽  
Ji-Feng Ying
Keyword(s):  
North China Craton ◽  
Lithospheric Mantle ◽  
North China ◽  
Basaltic Rocks ◽  
Secular Evolution

Secular evolution of the lithospheric mantle beneath the northern margin of the North China Craton: Insights from zoned olivine xenocrysts in Early Cretaceous basalts

2020 ◽  
Vol 132 (11-12) ◽  
pp. 2353-2366
Author(s):  
Yao Xu ◽  
Hongfu Zhang
Keyword(s):  
Early Cretaceous ◽  
North China Craton ◽  
Lithospheric Mantle ◽  
North China ◽  
Mantle Xenoliths ◽  
Liaoning Province ◽  
Northern Margin ◽  
Secular Evolution ◽  
The North ◽  
Peridotitic Mantle

Abstract Abundant zoned olivine xenocrysts from Early Cretaceous basalts of the Yixian Formation in western Liaoning Province, China, contain critical information about the nature and evolution of the lithospheric mantle of the northern North China Craton. These olivine xenocrysts are large (600–1600 µm), usually rounded and embayed, with well-developed cracks. Their cores have high and uniform forsterite (Fo) contents (88–91), similar to the peridotitic olivine entrained by regional Cenozoic basalts. Their rims have much lower Fo contents (74–82), comparable to phenocrysts (72–81) in the host basalts. These characteristics reveal that the zoned olivine has been disaggregated from mantle xenoliths and thus can be used to trace the underlying lithospheric mantle at the time of basaltic magmatism. The olivine cores have high oxygen isotope compositions (δ18OSMOW = 5.9–7.0‰) relative to the normal mantle value, suggesting that the Early Cretaceous lithospheric mantle was enriched and metasomatized mainly by melts/fluids released from subducted oceanic crust that had experienced low-temperature hydrothermal alteration. Preservation of zoned olivine xenocrysts in the Early Cretaceous basalts indicates that olivine-melt/fluid reaction could have been prevalent in the lithospheric mantle as an important mechanism for the transformation from old refractory (high-Mg) peridotitic mantle to young, fertile (low-Mg), and enriched lithospheric mantle during the early Mesozoic.

In-situ reaction-replacement origin of hornblendites in the Early Cretaceous Laiyuan complex, North China Craton, and implications for its tectono-magmatic evolution

2021 ◽  
Author(s):  
Jia Chang ◽  
Andreas Audétat ◽  
Jian-Wei Li
Keyword(s):  
Partial Melting ◽  
North China Craton ◽  
Lithospheric Mantle ◽  
Lower Crust ◽  
North China ◽  
Ultramafic Rocks ◽  
Magmatic Evolution ◽  
Mafic Magmas ◽  
Felsic Rocks

Abstract Two suites of amphibole-rich mafic‒ultramafic rocks associated with the voluminous intermediate to felsic rocks in the Early Cretaceous Laiyuan intrusive-volcanic complex (North China Craton) are studied here by detailed petrography, mineral- and melt inclusion chemistry, and thermobarometry to demonstrate an in-situ reaction-replacement origin of the hornblendites. Moreover, a large set of compiled and newly obtained geochronological and whole-rock elemental and Sr-Nd isotopic data are used to constrain the tectono-magmatic evolution of the Laiyuan complex. Early mafic‒ultramafic rocks occur mainly as amphibole-rich mafic‒ultramafic intrusions situated at the edge of the Laiyuan complex. These intrusions comprise complex lithologies of olivine-, pyroxene- and phlogopite-bearing hornblendites and various types of gabbroic rocks, which largely formed by in-situ crystallization of hydrous mafic magmas that experienced gravitational settling of early-crystallized olivine and clinopyroxene at low pressures of 0.10‒0.20 GPa (∼4‒8 km crustal depth); the hornblendites formed in cumulate zones by cooling-driven crystallization of 55‒75 vol% hornblende, 10‒20 vol% orthopyroxene and 3‒10 vol% phlogopite at the expense of olivine and clinopyroxene. A later suite of mafic rocks occurs as mafic lamprophyre dikes throughout the Laiyuan complex. These dikes occasionally contain some pure hornblendite xenoliths, which formed by reaction-replacement of clinopyroxene at high pressures of up to 0.97‒1.25 GPa (∼37‒47 km crustal depth). Mass balance calculations suggest that the olivine-, pyroxene- and phlogopite-bearing hornblendites in the early mafic‒ultramafic intrusions formed almost without melt extraction, whereas the pure hornblendites brought up by lamprophyre dikes required extraction of ≥ 20‒30 wt% residual andesitic to dacitic melts. The latter suggests that fractionation of amphibole in the middle to lower crust through the formation of reaction-replacement hornblendites is a viable way to produce adakite-like magmas. New age constraints suggest that the early mafic-ultramafic intrusions formed during ∼132‒138 Ma, which overlaps with the timespan of ∼126‒145 Ma recorded by the much more voluminous intermediate to felsic rocks of the Laiyuan complex. By contrast, the late mafic and intermediate lamprophyre dikes were emplaced during ∼110‒125 Ma. Therefore, the voluminous early magmatism in the Laiyuan complex was likely triggered by the retreat of the flat-subducting Paleo-Pacific slab, whereas the minor later, mafic to intermediate magmas may have formed in response to further slab sinking-induced mantle thermal perturbations. Whole-rock geochemical data suggest that the early mafic magmas formed by partial melting of subduction-related metasomatized lithospheric mantle, and that the early intermediate to felsic magmas with adakite-like signatures formed from mafic magmas through strong amphibole fractionation without plagioclase in the lower crust. The late mafic magmas seem to be derived from a slightly different metasomatized lithospheric mantle by lower degrees of partial melting.

scholarly journals Abnormal lithium isotope composition from the ancient lithospheric mantle beneath the North China Craton

2014 ◽  
Vol 4 (1) ◽  
Author(s):  
Yan-Jie Tang ◽  
Hong-Fu Zhang ◽  
Etienne Deloule ◽  
Ben-Xun Su ◽  
Ji-Feng Ying ◽  
...  
Keyword(s):  
North China Craton ◽  
Lithospheric Mantle ◽  
North China ◽  
Isotope Composition ◽  
Lithium Isotope ◽  
The North

Refertilization of lithospheric mantle beneath the North China Craton in Mesozoic: Evidence from in situ Sr isotopes of Fuxin peridotite

Lithos ◽  
2020 ◽  
Vol 364-365 ◽  
pp. 105478 ◽  
Author(s):  
Dongya Zou ◽  
Hongfu Zhang ◽  
Xiaoqi Zhang ◽  
Huiting Zhang ◽  
Benxun Su
Keyword(s):  
North China Craton ◽  
Lithospheric Mantle ◽  
North China ◽  
Sr Isotopes ◽  
The North

Thinning and destruction of the lithospheric mantle root beneath the North China Craton: A review

2019 ◽  
Vol 196 ◽  
pp. 102873 ◽  
Author(s):  
Jingao Liu ◽  
Ronghua Cai ◽  
D. Graham Pearson ◽  
James M. Scott
Keyword(s):  
North China Craton ◽  
Lithospheric Mantle ◽  
North China ◽  
The North
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