Abstract Geological mapping in 1970 of lower Cambrian outcrop in the eastern Flinders Ranges of South Australia included the description and naming of the Moorowie Formation, representing the uppermost Hawker Group. The mapping is supported by 885 m of measured sections. An early Cambrian regressive-marine shelf-margin succession is described, from the massive Wilkawillina Limestone (base), the grey laminated limestones, syndepositional slump-induced intraformational folds and breccias, collapse talus, and graded sediment gravity flow deposits of the Mernmerna Formation, terrace-edge attrition megabreccias and reefs of the Moorowie Formation, passing up to the red beds of the Billy Creek Formation (top). Rapid changes in sedimentary facies are attributed to basement block movements and diapiric influence on sedimentation with abrupt vertical relief and paleoslope indicated by syndepositional slumping and platform margin collapse. Tuffs in the Mernmerna Formation record contemporaneous volcanism. Massive archaeocyathan limestones, ooid grainstones, peloid limestones, reef-sourced megabreccias and red shales define five members in the overlying Moorowie Formation, signalling shallow-marine regressive conditions and the development of a biologically diverse carbonate platform seaward of evaporitic lagoons and supratidal sabkhas. The megabreccias of the Moorowie Formation formed as thin semi-autochthonous debris aprons or shallow tidal-channel infills resulting from gradual and persistent wave attrition and repeated collapse of a carbonate terrace that was vigorously reworked by tidal currents. Shale interbeds within the Moorowie Formation represent lightly channelised shallow-marine ramp deposits, with adjacent mud flats, as easterly equivalents of the Oraparinna Shale, the earliest of which formed the substrate to the attrition megabreccias. Emergent evaporite diapirs near Mt John and Mt Frome are the probable sources of coarse siliciclastics within the carbonates. Some of the siliciclastics were likely transported onto the carbonate platform by sandstorms or migrating dunes. Late in the Cambro-Ordovician Delamerian Orogeny, earlier salt diapirs at depth were compressed and reactivated as highly mobile evaporite-rubble breccias and intruded as small plugs and dykes into fissures in a lithified and folded cover. The intrusive breccias include metasediment and metabasic xenoclasts attributable to the Callanna Group, while diapir-related faults also host minor copper, lead and barite mineralisation. Documentation of this unique record contributes to wider investigations of the Ediacaran-to-early-Cambrian succession of the Flinders Ranges sector of the Arrowie Basin, adding to its global heritage values, effective management and appreciation by the wider community.

中文翻译：

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Moorowie 组的地质环境，下寒武纪霍克群，钱伯斯峡谷，东弗林德斯山脉，南澳大利亚

摘要 1970 年对南澳大利亚弗林德斯山脉东部下寒武统露头的地质测绘包括对代表最上层霍克群的 Moorowie 组的描述和命名。该映射由 885 m 的测量截面支持。描述了早期寒武纪海退-海相陆架边缘序列，包括大量的 Wilkawillina 石灰岩（基底）、灰色层状石灰岩、同沉积坍塌引起的地层内褶皱和角砾岩、崩塌距骨和 Mermmerna 组的分级沉积物重力流沉积物， Moorowie 组的阶地边缘磨损大角砾岩和珊瑚礁，向上传递到 Billy Creek 组的红层（顶部）。沉积相的快速变化归因于基底块体运动和底辟对沉积的影响，具有突然的垂直起伏和古斜坡，表现为同沉积塌陷和台缘塌陷。Mermmerna 组中的凝灰岩记录了同期的火山活动。巨大的古生物灰岩、鲕粒灰岩、球状灰岩、源自礁石的巨型角砾岩和红色页岩在上覆的 Moorowie 组中定义了五个成员，表明浅海海退条件和生物多样性碳酸盐平台的发展，向海蒸发泻湖和潮上沙布哈。Moorowie 组的巨型角砾岩形成为薄的半本土碎屑围裙或浅的潮汐通道填充物，这是由于波浪的逐渐和持续磨损以及被潮汐流剧烈改造的碳酸盐台地的反复坍塌而形成的。Moorowie 组内的页岩夹层代表轻度沟渠化的浅海斜坡沉积物，相邻的泥滩作为东侧的 Oraparinna 页岩，最早形成了磨损巨型角砾岩的基底。Mt John 和 Mt Frome 附近的新兴蒸发底辟是碳酸盐中粗硅质碎屑的可能来源。一些硅质碎屑很可能被沙尘暴或迁移的沙丘运送到碳酸盐台地。在寒武纪-奥陶纪德拉梅里造山运动后期，较早的深部盐底辟被压缩并重新激活为高度流动的蒸发岩碎石角砾岩，并以小塞子和堤坝的形式侵入岩化和折叠覆盖层的裂缝中。侵入性角砾岩包括属于 Callanna 群的变沉积物和变基性异种碎屑，而底辟相关断层也包含少量的铜、铅和重晶石矿化。记录这一独特记录有助于更广泛地调查阿罗里盆地弗林德斯山脉地区的埃迪卡拉纪到早寒武纪的演替，增加其全球遗产价值、有效管理和更广泛社区的欣赏。侵入性角砾岩包括属于 Callanna 群的变沉积物和变基性异种碎屑，而底辟相关断层也包含少量的铜、铅和重晶石矿化。记录这一独特记录有助于更广泛地调查阿罗里盆地弗林德斯山脉地区的埃迪卡拉纪到早寒武纪的演替，增加其全球遗产价值、有效管理和更广泛社区的欣赏。侵入性角砾岩包括属于 Callanna 群的变沉积物和变基性异种碎屑，而底辟相关断层也包含少量的铜、铅和重晶石矿化。记录这一独特记录有助于更广泛地调查阿罗里盆地弗林德斯山脉地区的埃迪卡拉纪到早寒武纪的演替，增加其全球遗产价值、有效管理和更广泛社区的欣赏。