石灰岩分类新方案

New Classification Scheme of Limestones

石灰岩分类是石灰岩成因及沉积相研究的基础,但目前在中国尚无一种普遍接受的石灰岩分类方案。由于不同的研究者采用不同的方案,造成了同一类石灰岩有不同的名字,或同一个名字含义不同等混乱现象。在充分研究前人分类方案的基础上,提出了一个新的石灰岩分类方案。根据结构组分类型及含量等特征,将石灰岩分为灰泥石灰岩、含颗粒灰泥石灰岩、颗粒质灰泥石灰岩、颗粒石灰岩(包括灰泥颗粒石灰岩、亮晶颗粒石灰岩)、礁石灰岩(包括亮晶礁石灰岩、灰泥礁石灰岩)、礁砾屑石灰岩(包括亮晶礁砾屑石灰岩、灰泥礁砾屑石灰岩)。每一类还可根据颗粒类型或造礁生物类型进一步细分。此外,还可采用三级命名法,根据矿物成分进一步细分。

Classification of limestones is the foundation for study of limestone origin and sedimentary facies. Because of the existence of various problems in previous classification schemes of limestones, no classification scheme of limestones is widely accepted at present in China. So different scholars adopt different classification schemes, resulting in chaos in naming and classification of limestones, such as dif- ferent names for one limestone, or different implications for one name. On the basis of analysis of previous classification schemes, this pa- per proposes a new classification scheme of limestones. Based on the types and content of textural components, limestones are divided into limemudstone, grain-bearing limemudstone, grainy limemudstone, grainstone （including limemud grainstone and sparry grainstone）, reef limestone （including limemud reef limestone and sparry reef limestone）, reef elast limestone （including span＇y reefclast limestone and limemud reefclast limestone）. Each type can be divided further based on grain type and reef-building organism type or based on mineral components by Class-3 nomenclature.