Abstract

This paper is devoted to the vein and dispersed carbonates from ejecta of mud volcanoes of Azerbaijan. The vein calcites are morphologically diverse and related to the healing of fracture systems. Most of them have δ¹³C (from –4 to +2‰) and δ¹⁸O (from +20 to +26‰) typical of marine carbonates. Some volcanoes contain fragments of the vein calcites enriched in light carbon (δ¹³C from –49.2 to –6‰), which could be formed in methane seep discharge sites during the Caspian Sea highstand period. In the dispersed carbonates from the clay pulp, the values of δ¹³C and δ¹⁸O change from –6.1 to +11.9‰ and from +23.8 to +32.7‰, respectively. It is shown that the studied carbonate matter has no genetic relation with the modern mud volcanic waters, which are characterized by high concentrations of \({\text{HCO}}_{3}^{-}\) (up to 8 g/L) and values of δ¹³C(TDIC) (δ¹³C_av= +20.0‰) and δ¹⁸O(H₂O) (δ¹⁸O_av= +4.0‰). Based on isotope characteristics and REE patterns, the vein calcites can be ascribed to the products of seawater-assisted postsedimentation transformation of sedimentary carbonates. The obtained data revealed a complete hydrodynamic isolation of mud volcanic channels from aquiferous complexes of host rocks.

中文翻译：

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阿塞拜疆库拉盆地泥火山喷出碳酸盐的地球化学和同位素特征

摘要

本文致力于阿塞拜疆泥火山喷出的碳酸盐和分散碳酸盐。静脉方解石形态多样，与骨折系统的愈合有关。他们中的大多数具有δ ¹³ C（从-4到+ 2‰）和δ ¹⁸ O（从20到+ 26‰）典型海相碳酸盐的。一些火山包含的片段的静脉方解石富集在光碳（δ ¹³ C来自-49.2至-6‰），这可能在甲烷渗漏放电部位里海高位周期期间形成。从粘土纸浆分散碳酸盐，δ的值¹³ C和δ ¹⁸O从–6.1变为+ 11.9‰，从+23.8变为+ 32.7‰。结果表明，所研究的碳酸盐物质与现代泥火山水没有遗传关系，其特征是高浓度的\（{\ text {HCO}} _ {3} ^ {-} \（8 g / L）和δ的值¹³ C（TDIC）（δ ¹³ C ^ _AV = + 20.0‰）和δ ¹⁸ ø（H ₂ O）（δ ¹⁸ ö _AV= + 4.0‰）。根据同位素特征和稀土元素分布规律，方解石可归因于沉积碳酸盐岩的海水辅助后沉降转化产物。获得的数据揭示了从火山岩含水复合物中完全隔离了泥火山通道的水动力。