The migration rule of the ore-forming fluids in the Meso-Cenozoic Basins, Southwestern Tianshan, China

The Wulagen pb-zn deposit and the Sareke copper deposit, two most representative strata-bound glutenite deposits in the Meso-Cenozoic Basins in Southwestern Tianshan, are the subjects of our study. The Wulagen pb-zn deposit occurred in the coarse sandy fine conglomerates in the Section 5 of the Lowe...

Full description

Bibliographic Details
Main Authors: JIA Runxing, FANG Weixuan
Format: Article
Language:zho
Published: Institute of Geomechanics, Chinese Academy of Geological Sciences 2021-08-01
Series:Dizhi lixue xuebao
Subjects:
Online Access:https://journal.geomech.ac.cn//article/doi/10.12090/j.issn.1006-6616.2021.27.04.046
_version_ 1828003515577925632
author JIA Runxing
FANG Weixuan
author_facet JIA Runxing
FANG Weixuan
author_sort JIA Runxing
collection DOAJ
description The Wulagen pb-zn deposit and the Sareke copper deposit, two most representative strata-bound glutenite deposits in the Meso-Cenozoic Basins in Southwestern Tianshan, are the subjects of our study. The Wulagen pb-zn deposit occurred in the coarse sandy fine conglomerates in the Section 5 of the Lower Cretaceous Kizilsu group(K1kz5) and have underwent weak tectonic reworking in the late period; The Sareke copper deposit occurred in anagenites in the upper section of Upper Jurassic Kuzigongsu formation (J3k2), and the northern part shows obvious tectonic reworking and enrichment mineralization, while the southern part shows discoloration and superposition mineralization after magmatic hydrothermal alteration. In order to study the migration law of ore-forming fluids and magmatic hydrothermal fluids in rocks, the porosity and permeability of the representative rocks dominated by sedimentation, tectonic reworking and magmatic hydrothermal alteration in the two mining areas were measured respectively. The test results show that the rocks in the Wulagen deposit area generally have low porosity and permeability than those in the Sareke deposit; the rocks in the Wulagen lead-zinc deposit and the northern part of the Sareke copper deposit have low porosity and permeability than their footwall rocks; the porosity and permeability of the rocks subjected to magmatic hydrothermal alteration in the southern part of the Sareke copper deposit are obviously lower than those not subjected to magmatic alteration, and the porosity and permeability of the footwall rocks of diabase dike are significantly lower than those of the upper rocks. According to the analysis of rock (ore) fabric, the changes of porosity and permeability after diagenesis and mineralization are closely related to the action of ore-forming fluids or magmatic hydrothermal fluids. In the Meso-Cenozoic strata-bound deposits in the southwestern Tianshan Mountains, rock strata with high porosity and permeability are preferred to be permeated, diffused, filled and metasomatized when ore-forming fluids rise along the cutting layer faults. The larger the gravel diameter is in the rock, the larger the gravel gap is; the greater the hardness of the rock, the easier it is to form structural cracks in the later tectonic deformation, and the more favorable it is for mineralization. This is also the important reason that the metal sulfide particles in the northern part of the Sareke copper deposit are obviously larger than those in the Wulagen lead-zinc deposit. In the process of magma intrusion, the alteration of the footwall quartz sandstone by the magmatic hydrothermal fluids is stronger than that of the hanging wall. The above results indicate that the stronger the mineralization of ore-forming fluids or magmatic hydrothermal fluids are in sedimentary basins, the lower the porosity and permeability of affected rocks will be after diagenesis and mineralization. The porosity and permeability of rocks can indirectly reflect the strength of mineralization and provides a theoretical basis for searching for ore shoots.
first_indexed 2024-04-10T06:59:52Z
format Article
id doaj.art-c080693de17d407599819095c384c4f8
institution Directory Open Access Journal
issn 1006-6616
language zho
last_indexed 2024-04-10T06:59:52Z
publishDate 2021-08-01
publisher Institute of Geomechanics, Chinese Academy of Geological Sciences
record_format Article
series Dizhi lixue xuebao
spelling doaj.art-c080693de17d407599819095c384c4f82023-02-28T01:27:52ZzhoInstitute of Geomechanics, Chinese Academy of Geological SciencesDizhi lixue xuebao1006-66162021-08-0127452954110.12090/j.issn.1006-6616.2021.27.04.046The migration rule of the ore-forming fluids in the Meso-Cenozoic Basins, Southwestern Tianshan, ChinaJIA RunxingFANG WeixuanThe Wulagen pb-zn deposit and the Sareke copper deposit, two most representative strata-bound glutenite deposits in the Meso-Cenozoic Basins in Southwestern Tianshan, are the subjects of our study. The Wulagen pb-zn deposit occurred in the coarse sandy fine conglomerates in the Section 5 of the Lower Cretaceous Kizilsu group(K1kz5) and have underwent weak tectonic reworking in the late period; The Sareke copper deposit occurred in anagenites in the upper section of Upper Jurassic Kuzigongsu formation (J3k2), and the northern part shows obvious tectonic reworking and enrichment mineralization, while the southern part shows discoloration and superposition mineralization after magmatic hydrothermal alteration. In order to study the migration law of ore-forming fluids and magmatic hydrothermal fluids in rocks, the porosity and permeability of the representative rocks dominated by sedimentation, tectonic reworking and magmatic hydrothermal alteration in the two mining areas were measured respectively. The test results show that the rocks in the Wulagen deposit area generally have low porosity and permeability than those in the Sareke deposit; the rocks in the Wulagen lead-zinc deposit and the northern part of the Sareke copper deposit have low porosity and permeability than their footwall rocks; the porosity and permeability of the rocks subjected to magmatic hydrothermal alteration in the southern part of the Sareke copper deposit are obviously lower than those not subjected to magmatic alteration, and the porosity and permeability of the footwall rocks of diabase dike are significantly lower than those of the upper rocks. According to the analysis of rock (ore) fabric, the changes of porosity and permeability after diagenesis and mineralization are closely related to the action of ore-forming fluids or magmatic hydrothermal fluids. In the Meso-Cenozoic strata-bound deposits in the southwestern Tianshan Mountains, rock strata with high porosity and permeability are preferred to be permeated, diffused, filled and metasomatized when ore-forming fluids rise along the cutting layer faults. The larger the gravel diameter is in the rock, the larger the gravel gap is; the greater the hardness of the rock, the easier it is to form structural cracks in the later tectonic deformation, and the more favorable it is for mineralization. This is also the important reason that the metal sulfide particles in the northern part of the Sareke copper deposit are obviously larger than those in the Wulagen lead-zinc deposit. In the process of magma intrusion, the alteration of the footwall quartz sandstone by the magmatic hydrothermal fluids is stronger than that of the hanging wall. The above results indicate that the stronger the mineralization of ore-forming fluids or magmatic hydrothermal fluids are in sedimentary basins, the lower the porosity and permeability of affected rocks will be after diagenesis and mineralization. The porosity and permeability of rocks can indirectly reflect the strength of mineralization and provides a theoretical basis for searching for ore shoots.https://journal.geomech.ac.cn//article/doi/10.12090/j.issn.1006-6616.2021.27.04.046meso-cenozoic basinvoidage and permeabilitytectonic deformation of basinore-forming fluidsouthwestern tianshan
spellingShingle JIA Runxing
FANG Weixuan
The migration rule of the ore-forming fluids in the Meso-Cenozoic Basins, Southwestern Tianshan, China
Dizhi lixue xuebao
meso-cenozoic basin
voidage and permeability
tectonic deformation of basin
ore-forming fluid
southwestern tianshan
title The migration rule of the ore-forming fluids in the Meso-Cenozoic Basins, Southwestern Tianshan, China
title_full The migration rule of the ore-forming fluids in the Meso-Cenozoic Basins, Southwestern Tianshan, China
title_fullStr The migration rule of the ore-forming fluids in the Meso-Cenozoic Basins, Southwestern Tianshan, China
title_full_unstemmed The migration rule of the ore-forming fluids in the Meso-Cenozoic Basins, Southwestern Tianshan, China
title_short The migration rule of the ore-forming fluids in the Meso-Cenozoic Basins, Southwestern Tianshan, China
title_sort migration rule of the ore forming fluids in the meso cenozoic basins southwestern tianshan china
topic meso-cenozoic basin
voidage and permeability
tectonic deformation of basin
ore-forming fluid
southwestern tianshan
url https://journal.geomech.ac.cn//article/doi/10.12090/j.issn.1006-6616.2021.27.04.046
work_keys_str_mv AT jiarunxing themigrationruleoftheoreformingfluidsinthemesocenozoicbasinssouthwesterntianshanchina
AT fangweixuan themigrationruleoftheoreformingfluidsinthemesocenozoicbasinssouthwesterntianshanchina
AT jiarunxing migrationruleoftheoreformingfluidsinthemesocenozoicbasinssouthwesterntianshanchina
AT fangweixuan migrationruleoftheoreformingfluidsinthemesocenozoicbasinssouthwesterntianshanchina