干旱区生态环境知识资源中心(Arid): Synsedimentary to early diagenetic rejuvenation of barite-sulfides ore deposits: Example of the Triassic intrakarstic mineralization in the Lodeve basin (France)

Arid

DOI	10.1016/j.marpetgeo.2020.104464
	Synsedimentary to early diagenetic rejuvenation of barite-sulfides ore deposits: Example of the Triassic intrakarstic mineralization in the Lodeve basin (France)
	Laurent, D.; Lopez, M.; Combes, P-J; Guerrot, C.; Spangenberg, J. E.; Gaucher, E. C.
通讯作者	Laurent, D
来源期刊	MARINE AND PETROLEUM GEOLOGY
ISSN	0264-8172
EISSN	1873-4073
出版年	2020
卷号	119
英文摘要	The exhumed Lodeve Basin (Herault, France) provides a rich suite of outcrops showing diagenetic Ba-Pb-Fe-Cu fronts trapped in karst system in Cambrian dolomites during the Triassic post-rift exhumation of the basin. The sedimentological analysis on 10 sites in the basin reveals that barites-sulfides fronts formed during humid-arid climate fluctuations and the emplacement of a shallow lake environment. The fabric of ore deposits, the microthermometry of fluid inclusions entrapped within barites and the strontium/sulfur isotopic compositions of barite-sulfides associations indicate two distinct groups of mineralizations, Type I and Type II, which are contemporaneous but resulting from different processes. The synsedimentary mineralization of the Type I, the presence of only primary single-phase liquid fluid inclusions within barite crystals and the gradual increase of delta S-34 for both barites and chalcopyrites with depth (from -7 to +18.9 parts per thousand V-CDT) suggest ore precipitation close to the vadose zone under bacterial sulfate reduction (BSR) in a confined sulfate-rich playa lake aquifer. The similar Sr-87/S-86 ratios between barites and the overlying Triassic evaporites indicate that the barium and strontium derived directly from the overlying sulfate-rich lake. For the Type II, the high homogenization temperature of fluid inclusions entrapped within barite (modal Th between 60 and 80 degrees C) and the association with hydrocarbon markers, confirm the participation of deeper basinal brines in addition to downward percolating sulfates derived from the lake environment. The high positive values of delta S-34 for both barites and sulfides are typical of a precipitation linked to the combined action between anaerobic oxidation of methane and sulfate reduction (AOM-SR) at the sulfate-methane transition zone (SMTZ) during hydrocarbon migration. Similar Sr-87/Sr-86 ratios between Middle Triassic barites and previous Late Permian barites confirm that the source of metals precipitated at the SMTZ originated from the dissolution of anterior ore deposits located in the sulfate-depleted zone. This study links very shallow metallogenesis processes to reworking of MVT ore deposits by the action of sulfate-reducing bacteria around hydrocarbon seeps in a karstic environment.
英文关键词	Karst Ore deposit Diagenetic barite Playa lake Sulfate reduction Fluid inclusions Sulfur and strontium isotopes
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000548925200008
WOS关键词	CONTINENTAL-MARGIN SEDIMENTS ; ANAEROBIC METHANE OXIDATION ; SYNTHETIC FLUID INCLUSIONS ; SULFATE REDUCTION ; DEEP BIOSPHERE ; BLAKE RIDGE ; BIOGEOCHEMICAL PROCESSES ; ISOTOPE FRACTIONATION ; MASS-SPECTROMETRY ; DISSOLVED BARIUM
WOS类目	Geosciences, Multidisciplinary
WOS研究方向	Geology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/325054
作者单位	[Laurent, D.; Lopez, M.; Combes, P-J] Univ Montpellier, Geosci Montpellier, F-34090 Montpellier, France; [Guerrot, C.] BRGM LAB, F-45060 Orleans, France; [Spangenberg, J. E.] Univ Lausanne, Inst Earth Surface Dynam IDYST, Lausanne, Switzerland; [Gaucher, E. C.] TOTAL Sci & Tech Ctr Jean Feger CSTJF TOTAL, F-64000 Pau, France
推荐引用方式 GB/T 7714	Laurent, D.,Lopez, M.,Combes, P-J,et al. Synsedimentary to early diagenetic rejuvenation of barite-sulfides ore deposits: Example of the Triassic intrakarstic mineralization in the Lodeve basin (France)[J],2020,119.
APA	Laurent, D.,Lopez, M.,Combes, P-J,Guerrot, C.,Spangenberg, J. E.,&Gaucher, E. C..(2020).Synsedimentary to early diagenetic rejuvenation of barite-sulfides ore deposits: Example of the Triassic intrakarstic mineralization in the Lodeve basin (France).MARINE AND PETROLEUM GEOLOGY,119.
MLA	Laurent, D.,et al."Synsedimentary to early diagenetic rejuvenation of barite-sulfides ore deposits: Example of the Triassic intrakarstic mineralization in the Lodeve basin (France)".MARINE AND PETROLEUM GEOLOGY 119(2020).