The link between an anorthosite complex and underlying olivine-Ti-magnetite-rich layered intrusion in Damiao, China: insights into magma chamber processes in the formation of Proterozoic massif-type anorthosites

Li-Xing Li, Hou-Min Li, Jian-Wei Zi, Birger Rasmussen, Stephen Sheppard, Yu-Bo Ma, Jie Meng, Zhe Song

Research output: Contribution to journalArticle

Abstract

Mafic-ultramafic intrusions comagmatic with Proterozoic massif-type anorthosites can provide insights into the parental magma from which large volumes of hyper-feldspathic rocks are produced. Recent deep drilling has unveiled a large olivine-Ti-magnetite-rich layered intrusion (named Dawusunangou) beneath the Damiao massif-type anorthosite complex in the North China Craton. The layered intrusion is composed of alternating olivine-Ti-magnetite-rich dark layers and plagioclase-rich light layers (ca. 35-80% plagioclase), with the latter also containing pod- or lens-shaped pyroxene-Ti-magnetite-rich aggregates. This layered intrusion shows low Mg# and REE patterns similar to the overlying Damiao anorthosite complex. Baddeleyite Pb-Pb geochronology yielded indistinguishable crystallization ages of ca. 1735Ma for both the Dawusunangou layered intrusion and the Damiao anorthosite complex, suggesting coeval emplacement. Using the average bulk compositions of the two intrusions, mass balance calculations assuming 30-40% Dawusunangou and 70-60% Damiao would give a composition similar to high-Al basaltic magma. Collectively, these features indicate that the Dawusunangou layered intrusion represents the mafic residues after the segregation of the Damiao anorthosites from high-Al basaltic parental magma. A short-lived magma chamber is thought to have supplied the two intrusions. In situ crystallization with variable nucleation rates for plagioclase combined with the mafic minerals crystallizing in equilibrium proportions resulted in the formation of repeated dark and light layers of the Dawusunangou layered intrusion. The two intrusions are interpreted to have formed by multiple magma injections, instead of continuous differentiation of one melt. The parental magma was derived from a depleted mantle source with significant crustal contribution during magma evolution. The large Nd-Hf isotopic variations suggest contamination by Paleoarchean to Neoarchean crust.

Original languageEnglish
Article number48
Number of pages21
JournalContributions to Mineralogy and Petrology
Volume174
Issue number6
DOIs
Publication statusPublished - Jun 2019

Cite this

@article{6dbc238ea9ef46d2bf7cd0fed9e9a894,
title = "The link between an anorthosite complex and underlying olivine-Ti-magnetite-rich layered intrusion in Damiao, China: insights into magma chamber processes in the formation of Proterozoic massif-type anorthosites",
abstract = "Mafic-ultramafic intrusions comagmatic with Proterozoic massif-type anorthosites can provide insights into the parental magma from which large volumes of hyper-feldspathic rocks are produced. Recent deep drilling has unveiled a large olivine-Ti-magnetite-rich layered intrusion (named Dawusunangou) beneath the Damiao massif-type anorthosite complex in the North China Craton. The layered intrusion is composed of alternating olivine-Ti-magnetite-rich dark layers and plagioclase-rich light layers (ca. 35-80{\%} plagioclase), with the latter also containing pod- or lens-shaped pyroxene-Ti-magnetite-rich aggregates. This layered intrusion shows low Mg# and REE patterns similar to the overlying Damiao anorthosite complex. Baddeleyite Pb-Pb geochronology yielded indistinguishable crystallization ages of ca. 1735Ma for both the Dawusunangou layered intrusion and the Damiao anorthosite complex, suggesting coeval emplacement. Using the average bulk compositions of the two intrusions, mass balance calculations assuming 30-40{\%} Dawusunangou and 70-60{\%} Damiao would give a composition similar to high-Al basaltic magma. Collectively, these features indicate that the Dawusunangou layered intrusion represents the mafic residues after the segregation of the Damiao anorthosites from high-Al basaltic parental magma. A short-lived magma chamber is thought to have supplied the two intrusions. In situ crystallization with variable nucleation rates for plagioclase combined with the mafic minerals crystallizing in equilibrium proportions resulted in the formation of repeated dark and light layers of the Dawusunangou layered intrusion. The two intrusions are interpreted to have formed by multiple magma injections, instead of continuous differentiation of one melt. The parental magma was derived from a depleted mantle source with significant crustal contribution during magma evolution. The large Nd-Hf isotopic variations suggest contamination by Paleoarchean to Neoarchean crust.",
keywords = "Olivine, Layered intrusion, Massif-type anorthosites, High-Al basalt, Residual melt, North China Craton, HF ISOTOPE GEOCHEMISTRY, HEBEI PROVINCE, PALEOPROTEROZOIC EVOLUTION, CRUSTAL EVOLUTION, FRACTIONAL CRYSTALLIZATION, GEOLOGICAL SIGNIFICANCE, LARAMIE ANORTHOSITE, ULTRAMAFIC ROCKS, VOLCANIC-ROCKS, EASTERN HEBEI",
author = "Li-Xing Li and Hou-Min Li and Jian-Wei Zi and Birger Rasmussen and Stephen Sheppard and Yu-Bo Ma and Jie Meng and Zhe Song",
year = "2019",
month = "6",
doi = "10.1007/s00410-019-1586-2",
language = "English",
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journal = "Contributions to Mineralogy & Petrology",
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The link between an anorthosite complex and underlying olivine-Ti-magnetite-rich layered intrusion in Damiao, China : insights into magma chamber processes in the formation of Proterozoic massif-type anorthosites. / Li, Li-Xing; Li, Hou-Min; Zi, Jian-Wei; Rasmussen, Birger; Sheppard, Stephen; Ma, Yu-Bo; Meng, Jie; Song, Zhe.

In: Contributions to Mineralogy and Petrology, Vol. 174, No. 6, 48, 06.2019.

Research output: Contribution to journalArticle

TY - JOUR

T1 - The link between an anorthosite complex and underlying olivine-Ti-magnetite-rich layered intrusion in Damiao, China

T2 - insights into magma chamber processes in the formation of Proterozoic massif-type anorthosites

AU - Li, Li-Xing

AU - Li, Hou-Min

AU - Zi, Jian-Wei

AU - Rasmussen, Birger

AU - Sheppard, Stephen

AU - Ma, Yu-Bo

AU - Meng, Jie

AU - Song, Zhe

PY - 2019/6

Y1 - 2019/6

N2 - Mafic-ultramafic intrusions comagmatic with Proterozoic massif-type anorthosites can provide insights into the parental magma from which large volumes of hyper-feldspathic rocks are produced. Recent deep drilling has unveiled a large olivine-Ti-magnetite-rich layered intrusion (named Dawusunangou) beneath the Damiao massif-type anorthosite complex in the North China Craton. The layered intrusion is composed of alternating olivine-Ti-magnetite-rich dark layers and plagioclase-rich light layers (ca. 35-80% plagioclase), with the latter also containing pod- or lens-shaped pyroxene-Ti-magnetite-rich aggregates. This layered intrusion shows low Mg# and REE patterns similar to the overlying Damiao anorthosite complex. Baddeleyite Pb-Pb geochronology yielded indistinguishable crystallization ages of ca. 1735Ma for both the Dawusunangou layered intrusion and the Damiao anorthosite complex, suggesting coeval emplacement. Using the average bulk compositions of the two intrusions, mass balance calculations assuming 30-40% Dawusunangou and 70-60% Damiao would give a composition similar to high-Al basaltic magma. Collectively, these features indicate that the Dawusunangou layered intrusion represents the mafic residues after the segregation of the Damiao anorthosites from high-Al basaltic parental magma. A short-lived magma chamber is thought to have supplied the two intrusions. In situ crystallization with variable nucleation rates for plagioclase combined with the mafic minerals crystallizing in equilibrium proportions resulted in the formation of repeated dark and light layers of the Dawusunangou layered intrusion. The two intrusions are interpreted to have formed by multiple magma injections, instead of continuous differentiation of one melt. The parental magma was derived from a depleted mantle source with significant crustal contribution during magma evolution. The large Nd-Hf isotopic variations suggest contamination by Paleoarchean to Neoarchean crust.

AB - Mafic-ultramafic intrusions comagmatic with Proterozoic massif-type anorthosites can provide insights into the parental magma from which large volumes of hyper-feldspathic rocks are produced. Recent deep drilling has unveiled a large olivine-Ti-magnetite-rich layered intrusion (named Dawusunangou) beneath the Damiao massif-type anorthosite complex in the North China Craton. The layered intrusion is composed of alternating olivine-Ti-magnetite-rich dark layers and plagioclase-rich light layers (ca. 35-80% plagioclase), with the latter also containing pod- or lens-shaped pyroxene-Ti-magnetite-rich aggregates. This layered intrusion shows low Mg# and REE patterns similar to the overlying Damiao anorthosite complex. Baddeleyite Pb-Pb geochronology yielded indistinguishable crystallization ages of ca. 1735Ma for both the Dawusunangou layered intrusion and the Damiao anorthosite complex, suggesting coeval emplacement. Using the average bulk compositions of the two intrusions, mass balance calculations assuming 30-40% Dawusunangou and 70-60% Damiao would give a composition similar to high-Al basaltic magma. Collectively, these features indicate that the Dawusunangou layered intrusion represents the mafic residues after the segregation of the Damiao anorthosites from high-Al basaltic parental magma. A short-lived magma chamber is thought to have supplied the two intrusions. In situ crystallization with variable nucleation rates for plagioclase combined with the mafic minerals crystallizing in equilibrium proportions resulted in the formation of repeated dark and light layers of the Dawusunangou layered intrusion. The two intrusions are interpreted to have formed by multiple magma injections, instead of continuous differentiation of one melt. The parental magma was derived from a depleted mantle source with significant crustal contribution during magma evolution. The large Nd-Hf isotopic variations suggest contamination by Paleoarchean to Neoarchean crust.

KW - Olivine

KW - Layered intrusion

KW - Massif-type anorthosites

KW - High-Al basalt

KW - Residual melt

KW - North China Craton

KW - HF ISOTOPE GEOCHEMISTRY

KW - HEBEI PROVINCE

KW - PALEOPROTEROZOIC EVOLUTION

KW - CRUSTAL EVOLUTION

KW - FRACTIONAL CRYSTALLIZATION

KW - GEOLOGICAL SIGNIFICANCE

KW - LARAMIE ANORTHOSITE

KW - ULTRAMAFIC ROCKS

KW - VOLCANIC-ROCKS

KW - EASTERN HEBEI

U2 - 10.1007/s00410-019-1586-2

DO - 10.1007/s00410-019-1586-2

M3 - Article

VL - 174

JO - Contributions to Mineralogy & Petrology

JF - Contributions to Mineralogy & Petrology

SN - 0010-7999

IS - 6

M1 - 48

ER -