陕西宁强胡家坝地区晚埃迪卡拉世高家山生物群岩相变化与化石保存关系  

RELATIONSHIPS BETWEEN PETROGRAPHIC VARIATIONS AND FOSSIL PRESERVATION OF THE LATE EDIACARAN GAOJIASHAN BIOTA IN THE HUJIABA AREA,NINGQIANG,SHAANXI

作　　者：马冀[1] 刘卓[1] 蔡耀平[1] 李朋[1] 林晋炎[1] 华洪[1] 

机构地区：[1]西北大学早期生命研究所,大陆动力学国家重点实验室,西北大学地质学系,西安710069

出　　处：《古生物学报》2008年第2期222-231,共10页Acta Palaeontologica Sinica

基　　金：西北大学地质学系国家理科人才培养基地基金(NoJ0630537);西北大学研究生自主创新项目(No07YZZ27);国家自然科学基金(No40572015);国家重点基础研究发展规划项目(No2006CB806400);长江学者和创新团队发展计划联合资助

摘　　要：我国上扬子陕西宁强-勉县境内产出埃迪卡拉纪晚期高家山生物群,根据大量野外追踪、实地观察与室内岩相分析,对碎屑岩相黄铁矿化软躯体化石的出现与岩相横向变化之间的关系以及相应的埋藏相进行初步探讨,认为胡家坝露头带为相对远离风暴源的沉积序列,最利于化石的保存;高家山露头带则属于相对靠近风暴源的沉积序列,化石保存潜力不如胡家坝露头带的沉积序列。The Gaojiashan biota of Ningqiang County, Shaanxi Province, is Late Ediacaran in age and typically yields Nama-type fossils. Early diagenetic pyritization played a pivotal role in fossil preservation. The correlation between fossil preservation and petrographic variations, however, remains poorly understood. Detailed field observations and laboratory petrographic analysis resulted in a series of interpretations for the lateral variations of sedimentary environment and differentiation of taphofacies. Two fossil outcrop belts have been identi fied in the field. Our work suggests that the Hujiaba outcrop belt is of more distal origin which resul ted from storm sedimentation, and thus has a higher preservation potential for Gaojiashan fossils. While the Gaojiashan outcrop belt is of more proximal origin and hence less favorable for the exceptional preservation of Gaojiashan fossils.

关 键 词：高家山生物群 岩相变化 埋藏相 风暴岩 埃迪卡拉系 陕南 

分 类 号：Q911[天文地球—古生物学与地层学]