Abstract The Ordovician Daylesford Limestone at Bowan Park and the Fossil Hill Limestone at Cliefden Caves have diagenetic and pedogenic features of microkarst, paleosols and calcrete associated with subaerial disconformities in their stratigraphic sequences, all of which, as an ensemble, have global geoheritage significance. The original shelly limestones, lime mudstones, and coralline limestones have selectively dissolved to form vugular limestone whose cavities have filled with sparry calcite and/or crystal silt. The limestones also have been calcretised to develop massive and laminar calcrete and calcrete ooids. Below disconformity surfaces are bleached limestone, crystal-silt and spar-filled fossil moulds and enlarged moulds, micro-breccia-filled moulds and fissures filled with crystal silt, calcrete pellets and calcrete ooids. The disconformity surfaces are irregular or undulating interfaces between lithologies, fissures and fissure-fills, and calcrete. Above disconformities there are limestone lithoclasts, remanié fossils, calcreted limestone, veined limestone, calcrete ooids, laminated calcrete, lithoclast grainstone, or calcrete-ooid grainstone, and lithoclasts with fossils moulds filled with crystal silt and/or spar. The lithological, stratigraphic and possibly landscape differences, make the subaerial diagenesis/pedogenesis in the Daylesford Limestone subtly different to that of the Fossil Hill Limestone. Subaerial disconformities and associated diagenesis/pedogenesis, as recorded in these formations, are not widely reported globally nor well represented in Ordovician limestones. The microkarst features provide insights into the types of subaerial diagenesis/pedogenesis during the Ordovician and into climate, landscape setting, paleohydrology, and groundwater/rainwater alkalinity. Consequently, the story of the Ordovician microkarst, paleosols and calcrete ooids is unique and globally of geoheritage significance as examples of subaerial alteration in an ancient high-rainfall, tropical climate volcanic island environment in a tectonically active region.

中文翻译：

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新南威尔士州博万公园和克利夫登洞穴奥陶系石灰岩的地下不整合、微岩溶和古土壤及其地质意义

摘要 博万公园奥陶系戴尔斯福特石灰岩和克利夫登洞化石山石灰岩具有微岩溶、古土壤和钙质岩溶的成岩和成土特征，地层层序存在地下不整合，具有全球地质遗产意义。原始的贝壳灰岩、石灰泥岩和珊瑚灰岩有选择地溶解形成孔洞石灰岩，其空腔充满了方解石和/或结晶粉砂。石灰岩也被钙化，形成块状和层状的钙质和钙质鲕粒。在不整合面之下是漂白的石灰岩、晶体粉砂和晶石填充的化石模具和扩大的模具、微角砾岩填充的模具和充满晶体粉砂、钙质颗粒和钙质卵石的裂缝。不整合面是岩性、裂隙和裂隙充填物以及钙质混凝土之间不规则或起伏的界面。上面的不整合有石灰岩碎石、残骸化石、钙化石灰岩、脉状石灰岩、钙质灰砾岩、层状钙质灰岩、碎屑颗粒岩或钙质-卵形颗粒岩，以及带有充满结晶粉砂和/或晶石的化石模具的碎屑岩。岩性、地层和可能的景观差异，使戴尔斯福特石灰岩的地下成岩作用/成土作用与化石山石灰岩的地下成岩作用/成土作用略有不同。在这些地层中记录的地下不整合和相关的成岩作用/成土作用在全球范围内没有得到广泛报道，也没有在奥陶纪石灰岩中得到很好的体现。微岩溶特征提供了对奥陶纪地下成岩作用/成土作用类型以及气候、景观环境、古水文和地下水/雨水碱度的见解。因此，奥陶纪微岩溶、古土壤和钙质卵石的故事是独一无二的，具有全球地质遗产意义，作为构造活跃地区古老的高降雨量、热带气候火山岛环境中地下蚀变的例子。