CAJ | 학술논문

Nyegga 麻坑区位于中挪威海大陆坡边缘 Storegga 海底滑坡的北缘，本研究的甲烷成因自生碳酸盐岩采自该麻坑区的CN03、Tobic、DoDo和G11四个麻坑内的海底面之上。碳酸盐岩孔洞和裂隙非常发育，部分碳酸盐岩胶结有大量的化学自养贝壳，表面被红褐色-黑色的铁锰氢氧化物覆盖。碳酸盐矿物以泥晶高镁方解石和针状文石为主导，伴有极少量的白云石。草莓状黄铁矿和球粒分布广泛，揭示了碳酸盐岩形成时的还原环境及形成过程中微生物的参与。碳酸盐岩的δ13CPDB值为–58.67‰~–47.46‰，清楚地表明这些甲烷成因自生碳酸盐岩经甲烷厌氧氧化过程而形成，且微生物成因的甲烷为其主导碳源。碳酸盐岩的δ13C 值还有效地指示了麻坑间沉积物甲烷的δ13C值的差异。
Nyegga 마갱구위우중나위해대륙파변연 Storegga 해저활파적북연，본연구적갑완성인자생탄산염암채자해마갱구적CN03、Tobic、DoDo화G11사개마갱내적해저면지상。탄산염암공동화렬극비상발육，부분탄산염암효결유대량적화학자양패각，표면피홍갈색-흑색적철맹경양화물복개。탄산염광물이니정고미방해석화침상문석위주도，반유겁소량적백운석。초매상황철광화구립분포엄범，게시료탄산염암형성시적환원배경급형성과정중미생물적삼여。탄산염암적δ13CPDB치위–58.67‰~–47.46‰，청초지표명저사갑완성인자생탄산염암경갑완염양양화과정이형성，차미생물성인적갑완위기주도탄원。탄산염암적δ13C 치환유효지지시료마갱간침적물갑완적δ13C치적차이。
Nyegga pockmark field is located at the northern flank of the Storegga Slide on the mid-Norwegian margin.The carbonatesamples were collected on the seafloor inside the pockmarks CN03,Tobic, DoDo and G11. The carbonates are characteristic of a high abundance of various voids and fissures,andare covered by a thin black or red-brown coating of Mn/Fe hydroxides. Samples from Pockmark Tobic are cemented with numerous chemosynthetic bivalves. The carbonateminerals are predominated by micritic high-magnesian calcite and acicular aragonite, with little dolomite. Peloids and framboidal pyrites are abundant, indicating the reducing conditions and microbial-mediated processesduring precipitation of the carbonates. Theδ13CPDB values range from–58.67 to–47.46‰, clearly demonstrating that the carbonates are cold-seep carbonatesderived from the processes ofanaerobic methane oxidationcoupling with sulfate reduction, and microbial methane is the dominant carbon source. Meanwhileδ13C values of the carbonateseffectively reflect the difference inδ13C values of methane in the correspondent pockmarks.