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洛阳龙门地区中寒武统张夏组为一套富含生物扰动的薄层微晶灰岩和厚层鲕粒灰岩沉积,根据沉积学和遗迹学特征,从中识别出6个遗迹组构,从下到上依次是:潮下低能碳酸盐岩台地中的Planolites montanus遗迹组构,潮下浅水较高能碳酸盐岩台地中的Palaeophycus tubularis-Thalassinoides horizontalis遗迹组构,高、低能交替的滨岸浅滩或开阔台地滩间坪或滩前沉积中的Skolithos linearis-Planolites montanus遗迹组构,深水低能开阔台地沉积中的模糊生物扰动遗迹组构,高能鲕粒浅滩中的Macaronichnus segregatis遗迹组构和潮下低能局限台地环境中的Palaeophycus heberti遗迹组构.龙门地区张夏组由无鲕粒滩的碳酸盐岩台地逐渐向发育厚层鲕粒滩的碳酸盐岩台地演化,沉积环境从滨岸浅滩逐渐演变为无鲕粒滩的开阔台地,并随着海退由深水、开阔台地逐渐变浅形成鲕粒滩、局限台地.
The Middle Cambrian Zhangxia Formation in the Longmen area of Luoyang is a suite of bioturbated thin-bedded microcrystalline limestone and thick oolite limestone deposits. According to sedimentology and relict features, six relic structures were identified, From bottom to top are the Planolites montanus relict structures in the subtidal low-energy carbonate platform, the Palaeophycus tubularis-Thalassinoides horizontalis relic structure in the sub-tidal shallow and higher-energy carbonate platform, The bankruptcy of Skolithos linearis-Planolites montanus in the alluvial or open platform beach, or the front of the beach, the fuzzy bioturbation structure in the deep-water low-open platform sediments, the Macaronichnus segregatis structure in the high-energy oolite shoal and the tide Palaeophycus heberti remains in a low-lying confined terrain environment.The Zhangxia Formation in the Longmen area gradually evolved from a carbonate platform without oolitic beach to a carbonate platform where thick oolitic beaches were developed, and the depositional environment evolved from the shore Shallows gradually evolved into an oolite-free platform open platform, and with the retreat from the deep water, open platform and gradually become shallow oolitic beach, limited platform.