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J. C. Duchesne I. Roelandts D. Demaiffe D. Weis 《Contributions to Mineralogy and Petrology》1985,90(2-3):214-225
Two major monzonoritic dykes occur in the Egersund-Ogna anorthositic massif (S.W. Norway): the Lomland dyke, which varies
from norite to monzonite, and the Vettaland ferronoritic dyke. They are characterized by high Fe, Ti and P contents, low SiO2, variable K2O (0.5%–4.5%) and high Fe/Mg ratios. Small variations in REE distribution are observed inside the Lomland dyke [La/Yb=12;
LREE ca. 150–180 (chondrite-normalized values), neutral to slightly positive Eu anomaly]. Part of the Vettaland dyke is severely
depleted in Zr, Rb and REE and shows a positive Eu anomaly. All rocks are depleted in U and Th, and show very low Cr and Ni
contents, as well as high Sr contents (400–600 ppm). Variation within the Lomland dyke is satisfactorily ex-plained through
subtraction of an apatite-bearing noritic cumulate. The role of apatite is predominant in controlling the REE behaviour. Eutectic
partial melting of a Fe-rich noritic cumulate (containing apatite) under low pH2O conditions is suggested for the Vettaland dyke by REE modelling. Sr isotopic initial ratios are different in Lomland (ca.
0.708) and Vettaland (ca. 0.706) dykes. These values preclude direct derivation from the mantle as well as comagmatic relationship
with anorthosite. Contamination of a mantle derived magma by deep crustal material or anatexis of the LIL depleted lower crust
is compatible with the low U and Th contents, and with the Pb isotopic ratios. The Vettaland partial melting process is extended
to all monzonoritic types, the necessary heat being provided by the high temperature anorthositic crystal mush.
Chargé de Recherches du F.N.R.S (Belgium) 相似文献
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《《地质学报》英文版》1999,73(4):488-491
The Reservior Characteristics of Lower Ordovician Dolomites Below Pre-Mesozoic Unconformity in Yakela Fault-convex, Tarim Basin The Blueschist Belt in the Shuanghu Region, Central-Northern Tibet and Its Tectonic Implications Reef Palaeopool and Prediction of Buried Reefs in the Lower Permian Series from Shiwandashan Basin of Guangri Province Geochemistry of Rare Earth Elements in Late Paleozoic Coals in the North China Phase Transition and Composition Change of Minerals from Melting Experiment of Two Kinds of Metamorphics in Fuping Group, Pingshan, Hebei Province, China Palaeoecology and Palaeoenvironment of the Jehol Biota — A Palaeoecological and Palaeoenvironmental Reconstruction of Conchostracan Palaeocommunities in the Northern Hebei-Western Liaoning Area Research on Micro-FT.IR of Macerals of C-P Coals in the Bohal Bay Basin Self-similar Texture of the Mid—Longling—Ruili Strike-Slip System and the Location of Hydrothermal Deposits Metamorphism of the Eclogites from the ZK703 drillhole in Donghai, South Sulu (Jiangsu-Shandong) Ultrahigh-pressure Metamorphic Belt, Eastern China 相似文献
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