Recrystallization and hydrothermal growth of high U–Th zircon in the Weondong deposit, Korea

Record of post-magmatic alteration

Changyun Park, Yun Goo Song, Donghoon Chung, Il Mo Kang, Chuluunbaatar Khulganakhuu, Keewook Yi

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

In this study, we investigate zircons with high U and Th contents of 12,000–24,000 and 11,000–40,000 ppm, respectively, from leucocratic granite in the Weondong region of South Korea. Hydrothermally epitaxial growth textures are observed in addition to four distinct textures with different backscattered electron (BSE) intensities within single zircon crystals. We describe the internal textures of the zircon crystals and define the chemical characteristics of each textural domain. The zircon crystals show internally recrystallized and externally crystallized textures, supporting the concept of post-magmatic fluid control. After crystallization of the primary zircon by late magmatism, four types of secondary textures were developed. The type-I domain shows patchy forms within the primary domain due to the structural and chemical recrystallization of self-irradiated zircon by a fluid-dominated diffusion reaction process. The type-II domain is characterized by a pure zircon composition, mineral inclusions (mainly thorite), and micropores due to chemical recrystallization by a coupled dissolution–reprecipitation process during interaction with aqueous fluids. The type-III domain is the purest zircon, is interconnected with type-II, and formed by a second coupled dissolution–reprecipitation process. The type-IV domain is the hydrothermal recrystallization/overgrowth texture formed by the direct crystallization process from fluorine-enriched, zircon-saturated aqueous fluid. These results indicate that the zircon crystals were formed sequentially or intermittently through multi-genetic processes by post-magmatic fluids. Furthermore, we conclude that F-enriched post-magmatic fluid migrated large amounts of zirconium, resulting in the typical overgrowth texture of zircon.

Original languageEnglish
Pages (from-to)268-285
Number of pages18
JournalLithos
Volume260
DOIs
Publication statusPublished - 2016 Sep 1

Fingerprint

zircon
Deposits
Textures
texture
Fluids
fluid
crystal
Crystals
Crystallization
crystallization
Fluorine
fluorine
Epitaxial growth
Minerals
magmatism
granite
electron
Electrons
mineral
Chemical analysis

All Science Journal Classification (ASJC) codes

  • Geology
  • Geochemistry and Petrology

Cite this

Park, Changyun ; Song, Yun Goo ; Chung, Donghoon ; Kang, Il Mo ; Khulganakhuu, Chuluunbaatar ; Yi, Keewook. / Recrystallization and hydrothermal growth of high U–Th zircon in the Weondong deposit, Korea : Record of post-magmatic alteration. In: Lithos. 2016 ; Vol. 260. pp. 268-285.
@article{9e93b66091754a0490780c6d08674da2,
title = "Recrystallization and hydrothermal growth of high U–Th zircon in the Weondong deposit, Korea: Record of post-magmatic alteration",
abstract = "In this study, we investigate zircons with high U and Th contents of 12,000–24,000 and 11,000–40,000 ppm, respectively, from leucocratic granite in the Weondong region of South Korea. Hydrothermally epitaxial growth textures are observed in addition to four distinct textures with different backscattered electron (BSE) intensities within single zircon crystals. We describe the internal textures of the zircon crystals and define the chemical characteristics of each textural domain. The zircon crystals show internally recrystallized and externally crystallized textures, supporting the concept of post-magmatic fluid control. After crystallization of the primary zircon by late magmatism, four types of secondary textures were developed. The type-I domain shows patchy forms within the primary domain due to the structural and chemical recrystallization of self-irradiated zircon by a fluid-dominated diffusion reaction process. The type-II domain is characterized by a pure zircon composition, mineral inclusions (mainly thorite), and micropores due to chemical recrystallization by a coupled dissolution–reprecipitation process during interaction with aqueous fluids. The type-III domain is the purest zircon, is interconnected with type-II, and formed by a second coupled dissolution–reprecipitation process. The type-IV domain is the hydrothermal recrystallization/overgrowth texture formed by the direct crystallization process from fluorine-enriched, zircon-saturated aqueous fluid. These results indicate that the zircon crystals were formed sequentially or intermittently through multi-genetic processes by post-magmatic fluids. Furthermore, we conclude that F-enriched post-magmatic fluid migrated large amounts of zirconium, resulting in the typical overgrowth texture of zircon.",
author = "Changyun Park and Song, {Yun Goo} and Donghoon Chung and Kang, {Il Mo} and Chuluunbaatar Khulganakhuu and Keewook Yi",
year = "2016",
month = "9",
day = "1",
doi = "10.1016/j.lithos.2016.05.026",
language = "English",
volume = "260",
pages = "268--285",
journal = "Lithos",
issn = "0024-4937",
publisher = "Elsevier",

}

Recrystallization and hydrothermal growth of high U–Th zircon in the Weondong deposit, Korea : Record of post-magmatic alteration. / Park, Changyun; Song, Yun Goo; Chung, Donghoon; Kang, Il Mo; Khulganakhuu, Chuluunbaatar; Yi, Keewook.

In: Lithos, Vol. 260, 01.09.2016, p. 268-285.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Recrystallization and hydrothermal growth of high U–Th zircon in the Weondong deposit, Korea

T2 - Record of post-magmatic alteration

AU - Park, Changyun

AU - Song, Yun Goo

AU - Chung, Donghoon

AU - Kang, Il Mo

AU - Khulganakhuu, Chuluunbaatar

AU - Yi, Keewook

PY - 2016/9/1

Y1 - 2016/9/1

N2 - In this study, we investigate zircons with high U and Th contents of 12,000–24,000 and 11,000–40,000 ppm, respectively, from leucocratic granite in the Weondong region of South Korea. Hydrothermally epitaxial growth textures are observed in addition to four distinct textures with different backscattered electron (BSE) intensities within single zircon crystals. We describe the internal textures of the zircon crystals and define the chemical characteristics of each textural domain. The zircon crystals show internally recrystallized and externally crystallized textures, supporting the concept of post-magmatic fluid control. After crystallization of the primary zircon by late magmatism, four types of secondary textures were developed. The type-I domain shows patchy forms within the primary domain due to the structural and chemical recrystallization of self-irradiated zircon by a fluid-dominated diffusion reaction process. The type-II domain is characterized by a pure zircon composition, mineral inclusions (mainly thorite), and micropores due to chemical recrystallization by a coupled dissolution–reprecipitation process during interaction with aqueous fluids. The type-III domain is the purest zircon, is interconnected with type-II, and formed by a second coupled dissolution–reprecipitation process. The type-IV domain is the hydrothermal recrystallization/overgrowth texture formed by the direct crystallization process from fluorine-enriched, zircon-saturated aqueous fluid. These results indicate that the zircon crystals were formed sequentially or intermittently through multi-genetic processes by post-magmatic fluids. Furthermore, we conclude that F-enriched post-magmatic fluid migrated large amounts of zirconium, resulting in the typical overgrowth texture of zircon.

AB - In this study, we investigate zircons with high U and Th contents of 12,000–24,000 and 11,000–40,000 ppm, respectively, from leucocratic granite in the Weondong region of South Korea. Hydrothermally epitaxial growth textures are observed in addition to four distinct textures with different backscattered electron (BSE) intensities within single zircon crystals. We describe the internal textures of the zircon crystals and define the chemical characteristics of each textural domain. The zircon crystals show internally recrystallized and externally crystallized textures, supporting the concept of post-magmatic fluid control. After crystallization of the primary zircon by late magmatism, four types of secondary textures were developed. The type-I domain shows patchy forms within the primary domain due to the structural and chemical recrystallization of self-irradiated zircon by a fluid-dominated diffusion reaction process. The type-II domain is characterized by a pure zircon composition, mineral inclusions (mainly thorite), and micropores due to chemical recrystallization by a coupled dissolution–reprecipitation process during interaction with aqueous fluids. The type-III domain is the purest zircon, is interconnected with type-II, and formed by a second coupled dissolution–reprecipitation process. The type-IV domain is the hydrothermal recrystallization/overgrowth texture formed by the direct crystallization process from fluorine-enriched, zircon-saturated aqueous fluid. These results indicate that the zircon crystals were formed sequentially or intermittently through multi-genetic processes by post-magmatic fluids. Furthermore, we conclude that F-enriched post-magmatic fluid migrated large amounts of zirconium, resulting in the typical overgrowth texture of zircon.

UR - http://www.scopus.com/inward/record.url?scp=84975810927&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84975810927&partnerID=8YFLogxK

U2 - 10.1016/j.lithos.2016.05.026

DO - 10.1016/j.lithos.2016.05.026

M3 - Article

VL - 260

SP - 268

EP - 285

JO - Lithos

JF - Lithos

SN - 0024-4937

ER -