TY - JOUR

T1 - Physicochemical Parameters of Ultrabasic Magmatic Systems of the Northeastern Siberian Platform (Data on Melt Inclusions in Chromian Spinel)

AU - Simonov, V. A.

AU - Vasil’ev, Yu R.

AU - Kotlyarov, A. V.

AU - Nikolenko, E. I.

AU - Alifirova, T. A.

AU - Sharygin, V. V.

AU - Aulbach, S.

N1 - Симонов В.А., Васильев Ю.Р., Котляров А.В., Николенко Е.И., Алифирова Т.А., Шарыгин В.В., АУЛБАХ С. Физико-химические параметры ультраосновных магматических систем северо-востока Сибирской платформы (данные по расплавным включениям в хромшпинелиде) // Геология и геофизика. – 2022. – Т. 63. - № 12. – С. 1630-1652. Работа выполнена в рамках государственного задания ИГМ СО РАН при поддержке Министерства науки и высшего образования Российской Федерации, договора № 14.Y26.31.0029, гранта РФФИ (18-45-140027).

PY - 2022/12/1

Y1 - 2022/12/1

N2 - Experimental studies and analysis of silicate inclusions testify to the magmatic genesis of part of chromian spinel from the Triassic deposits of the northeastern Siberian Platform. The compositions of melt inclusions in the chromian spinel show the participation of alkaline (potassic) magmas in their crystallization. Most data indicate the presence of magmatic systems similar to melts in the Guli ultrabasic massif in the northern Siberian Platform. Studies of the distribution of trace and rare-earth elements in the melt inclusions show the existence of several magmatic systems. These are, first of all, magmas that formed Guli-type ultrabasic massifs and gave rise to meimechites and picrites in the Maimecha–Kotui province. There are also plume-related magmatic systems with kimberlites, lampro-phyres, and/or other continental “hot spots”. The composition of the melt inclusions suggests the existence of several types of the primary sources of chromian spinel in the northeastern Siberian Platform, which confirms the earlier data on the heterogeneous composition of the deposits of the diamondiferous Carnian (Upper Triassic) Stage. Applying computer modeling with the well-known COMAGMAT, PETROLOG, and WinPLtb programs as well as the Ol–Sp geothermometers based on the melt inclusions in chromian spinel from the Triassic deposits of the northeastern Siberian Platform, we have determined the P–T conditions of crystallization of minerals in the igneous rocks being the sources of the examined chromites. The temperature of liquidus crystallization of chromian spinel is 1324–1275 ºC. The P–T conditions of formation of olivine and clinopyroxene inclusions in it are estimated at ca. 4.5–4.1 kbar, 1510–1150 ºC and 3.2–1.0 kbar, 1285–1200 ºC, respectively.

AB - Experimental studies and analysis of silicate inclusions testify to the magmatic genesis of part of chromian spinel from the Triassic deposits of the northeastern Siberian Platform. The compositions of melt inclusions in the chromian spinel show the participation of alkaline (potassic) magmas in their crystallization. Most data indicate the presence of magmatic systems similar to melts in the Guli ultrabasic massif in the northern Siberian Platform. Studies of the distribution of trace and rare-earth elements in the melt inclusions show the existence of several magmatic systems. These are, first of all, magmas that formed Guli-type ultrabasic massifs and gave rise to meimechites and picrites in the Maimecha–Kotui province. There are also plume-related magmatic systems with kimberlites, lampro-phyres, and/or other continental “hot spots”. The composition of the melt inclusions suggests the existence of several types of the primary sources of chromian spinel in the northeastern Siberian Platform, which confirms the earlier data on the heterogeneous composition of the deposits of the diamondiferous Carnian (Upper Triassic) Stage. Applying computer modeling with the well-known COMAGMAT, PETROLOG, and WinPLtb programs as well as the Ol–Sp geothermometers based on the melt inclusions in chromian spinel from the Triassic deposits of the northeastern Siberian Platform, we have determined the P–T conditions of crystallization of minerals in the igneous rocks being the sources of the examined chromites. The temperature of liquidus crystallization of chromian spinel is 1324–1275 ºC. The P–T conditions of formation of olivine and clinopyroxene inclusions in it are estimated at ca. 4.5–4.1 kbar, 1510–1150 ºC and 3.2–1.0 kbar, 1285–1200 ºC, respectively.

KW - P–T conditions of magmatic processes

KW - Ultrabasic magmatic systems

KW - melt inclusions in chromian spinel

KW - northeastern Siberian Platform

UR - https://www.scopus.com/inward/record.url?eid=2-s2.0-85144707780&partnerID=40&md5=a658c2efc72b139d4752cb813286922d

UR - https://www.mendeley.com/catalogue/7611cfb7-e738-3bb4-8cbc-3f77ecafa47a/

U2 - 10.2113/RGG20204313

DO - 10.2113/RGG20204313

M3 - Article

VL - 63

SP - 1354

EP - 1373

JO - Russian Geology and Geophysics

JF - Russian Geology and Geophysics

SN - 1068-7971

IS - 12

ER -