TY - JOUR

T1 - The role of eclogites in the redistribution of water in the subcontinental mantle of the Siberian craton

T2 - results of determination of the water content in minerals from the Udachnaya pipe eclogites

AU - Kolesnichenko, M. V.

AU - Zedgenizov, D. A.

AU - Ragozin, A. L.

AU - Litasov, K. D.

AU - Shatsky, V. S.

N1 - Publisher Copyright: © 2018

PY - 2018/7/1

Y1 - 2018/7/1

N2 - A comprehensive study of 26 mafic mantle xenoliths from the Udachnaya kimberlite pipe was carried out. The contents of major and trace elements, equilibrium temperature parameters, and water content in the rock-forming minerals were determined. The temperatures of formation of the studied rocks are estimated at 800–1300 °C. According to IR spectroscopy data, the water content in clinopyroxenes from the studied eclogites varies from values below the detection limit to 99 ppm. The IR spectra of garnets lack bands of water. The water content in clinopyroxene and orthopyroxene from garnet websterite is 72 and 8 ppm, respectively. The water content in the average rock, calculated from the ratio of the rock-forming minerals, varies from a few to 55 ppm. No relationship among the water content, equilibrium temperatures, and rock composition is established. The low water contents in the eclogites are close to the earlier determined water contents in peridotites from the same pipe and are, most likely, due to the re-equilibration of the eclogites with the rocks of the peridotitic lithospheric mantle. The dehydration of the protolith during its subduction and the partial melting of eclogites before their removal by kimberlitic magma to the surface might be an additional cause of the low water contents in the mantle eclogite xenoliths.

AB - A comprehensive study of 26 mafic mantle xenoliths from the Udachnaya kimberlite pipe was carried out. The contents of major and trace elements, equilibrium temperature parameters, and water content in the rock-forming minerals were determined. The temperatures of formation of the studied rocks are estimated at 800–1300 °C. According to IR spectroscopy data, the water content in clinopyroxenes from the studied eclogites varies from values below the detection limit to 99 ppm. The IR spectra of garnets lack bands of water. The water content in clinopyroxene and orthopyroxene from garnet websterite is 72 and 8 ppm, respectively. The water content in the average rock, calculated from the ratio of the rock-forming minerals, varies from a few to 55 ppm. No relationship among the water content, equilibrium temperatures, and rock composition is established. The low water contents in the eclogites are close to the earlier determined water contents in peridotites from the same pipe and are, most likely, due to the re-equilibration of the eclogites with the rocks of the peridotitic lithospheric mantle. The dehydration of the protolith during its subduction and the partial melting of eclogites before their removal by kimberlitic magma to the surface might be an additional cause of the low water contents in the mantle eclogite xenoliths.

KW - eclogite

KW - lithospheric mantle

KW - Siberian craton

KW - water

KW - NOMINALLY ANHYDROUS MINERALS

KW - H2O STORAGE CAPACITY

KW - PERIDOTITE MASSIF

KW - HIGH-PRESSURE

KW - LITHOSPHERIC MANTLE

KW - CONTINENTAL-CRUST

KW - YAKUTIAN KIMBERLITES

KW - DIAMOND-BEARING ECLOGITE

KW - EARTHS UPPER-MANTLE

KW - KIMBERLITE PIPE

UR - http://www.scopus.com/inward/record.url?scp=85049984148&partnerID=8YFLogxK

U2 - 10.1016/j.rgg.2018.07.004

DO - 10.1016/j.rgg.2018.07.004

M3 - Article

AN - SCOPUS:85049984148

VL - 59

SP - 763

EP - 779

JO - Russian Geology and Geophysics

JF - Russian Geology and Geophysics

SN - 1068-7971

IS - 7

ER -