TY - JOUR

T1 - Zr-Th-REE Mineralization Associated with Albite–Aegirine-Bearing Rocks of the Burpala Alkaline Intrusion (North Baikal Region, South Margin of the Siberian Craton)

AU - Izbrodin, Ivan Aleksandrovich

AU - Doroshkevich, Anna Gennadievna

AU - Starikova, Anastasia Evgenyevna

AU - Malyutina, Alexandra Vladislavovna

AU - Moroz, Tatyana Nikolaevna

AU - Sharygin, Igor Sergeevich

N1 - The geology of the region was studied within the framework of the state assignment of IGM SB RAS (22041400241-5), while mineralogical studies were supported by the Russian Science Foundation (RSF) under grant #22-17-00078-P (https://rscf.ru/en/project/22-17-00078/, accessed on 12 July 2025).

PY - 2025/7/16

Y1 - 2025/7/16

N2 - The rocks of the Burpala alkaline intrusion contain a wide range of rare minerals that concentrate rare earth elements (REEs), Nb, Th, Li, and other incompatible elements. One of the examples of the occurrence of such mineralization is albite–aegirine rocks located at the contact zone between the intrusion and the host terrigenous–sedimentary rock. In albite–aegirine rocks, cubic crystals of “metaloparite”, partially or completely substituted by bastnäsite-(Ce) and polymorphic TiO2 phases (anatase and rutile) mainly represent the rare metal minerals. In albite–aegirine rocks, trace element minerals are predominantly represented by cubic crystals of “metaloparite”, which are partially or completely replaced by bastnäsite-(Ce) and polymorphic TiO2 phases such as anatase and rutile. Additionally, Th-bearing zircon (up to 17.7 wt% ThO2) and a variety of unidentified minerals containing REEs, Th, and Nb were detected. The obtained data indicate that bastnäsite-(Ce) is the result of the recrystallization of “metaloparite” accompanied by the formation of Th-bearing zircon and Nb-bearing rutile (up to 9.9 wt% Nb2O5) and the separation of various undiagnosed, unidentified LREE phases. Our studies show that remobilization of LREEs, HFSEs, and local enrichment of rocks in these elements occurred due to the effects of residual fluid enriched in fluorine and carbon dioxide.

AB - The rocks of the Burpala alkaline intrusion contain a wide range of rare minerals that concentrate rare earth elements (REEs), Nb, Th, Li, and other incompatible elements. One of the examples of the occurrence of such mineralization is albite–aegirine rocks located at the contact zone between the intrusion and the host terrigenous–sedimentary rock. In albite–aegirine rocks, cubic crystals of “metaloparite”, partially or completely substituted by bastnäsite-(Ce) and polymorphic TiO2 phases (anatase and rutile) mainly represent the rare metal minerals. In albite–aegirine rocks, trace element minerals are predominantly represented by cubic crystals of “metaloparite”, which are partially or completely replaced by bastnäsite-(Ce) and polymorphic TiO2 phases such as anatase and rutile. Additionally, Th-bearing zircon (up to 17.7 wt% ThO2) and a variety of unidentified minerals containing REEs, Th, and Nb were detected. The obtained data indicate that bastnäsite-(Ce) is the result of the recrystallization of “metaloparite” accompanied by the formation of Th-bearing zircon and Nb-bearing rutile (up to 9.9 wt% Nb2O5) and the separation of various undiagnosed, unidentified LREE phases. Our studies show that remobilization of LREEs, HFSEs, and local enrichment of rocks in these elements occurred due to the effects of residual fluid enriched in fluorine and carbon dioxide.

KW - Burpala alkaline intrusion

KW - North Baikal alkaline province

KW - Th-bearing zircon

KW - aegirine metasomatites

KW - “metaloparite”

UR - https://www.mendeley.com/catalogue/8498548a-7ef2-3990-a897-c33e044719c6/

UR - https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=105011665587&origin=inward

U2 - 10.3390/min15070742

DO - 10.3390/min15070742

M3 - Article

VL - 15

JO - Minerals

JF - Minerals

SN - 2075-163X

IS - 7

M1 - 742

ER -