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对在南海北部大陆坡新发现的冷泉碳酸盐结核进行了研究．结果表明,碳酸盐结核由含铁白云石、菱铁矿、少量文石和方解石以及非碳酸盐矿物针铁矿、石英和黏土矿物组成．含铁白云石和菱铁矿呈微晶结构,显示了直接从冷泉流体中沉淀出来的特征．含铁白云石/菱铁矿的δ~(13)C值为-18．24‰～-36．07‰,δ~(18)O值为0．42‰～2．76‰,中等亏损的~(13)C表明碳来源于热解成因气或混合气,是指示该海域存在甲烷冷泉的重要证据．结核表面分布有管状蠕虫遗迹,蠕虫生活环境与冷泉流体的存在有关．半固结结核中分布有蜂状排溢孔和流体通道,其未被碳酸盐或沉积物充填．研究表明,碳酸盐结核区海底可能存在孔径为200～600μm仍在喷溢的天然气微渗漏系统．
The cold spring carbonate tuberculosis newly discovered on the continental slope in the northern South China Sea was studied. The results show that carbonate nodules consist of iron-bearing dolomite, siderite, a small amount of aragonite and calcite, and non-carbonate mineral goethite, quartz and clay minerals. Ferrous dolomite and siderite are microcrystalline structures that show the characteristics of precipitation directly from the cold spring fluid. The δ ~ (13) C value of iron-bearing dolomite / siderite is -18.24 ‰ ~ -36.07 ‰, the δ ~ (18) O value is 0.42 ‰ ~ 2.76 ‰, and the average loss ~ (13) C indicates that carbon comes from pyrogenic gas or gas mixture, which is an important indicator of the presence of methane cold springs in this area. Tubercular distribution of tubular worms ruins, living environment and the presence of cold spring fluid. Semi-solidified nodules distribute bee-like vent holes and fluid channels that are not filled with carbonate or sediment. Studies have shown that there may be natural gas microleakage systems with a pore size of 200-600 μm in the carbonate nodules.