Abstract Jurassic deposits of shallow to marginal marine (delta) environments are widely reported from different continents of the world. This study shows inter-relationship of the animal-sediment behaviours in shallow and marginal marine conditions, suggesting an interpretation of the possible ichnodisparity. The Jurassic succession exposed at Washtawa Dome and Adhoi Anticline of Wagad highland, Kachchh comprises an approximately 341 m thick succession, divided into two formations – Lower Washtawa and Upper Wagad Sandstone. Eight sparsely to highly bioturbated sedimentary units show twenty-three identifiable ichnospecies from fifteen ichnogenera representing five ichnoassemblages broadly attributable to the Skolithos and the Cruziana ichnofacies, and developed in shallow-marine strandplain shoreface and delta depositional facies. The relative frequency statistical data reveals the dominant occurrence of feeding structures generated by polychaetes preferentially in quartz arenites. These structures represent sub-horizontal, sub-vertical and complex burrows, and show twelve and six categories of architectural designing Callovian-Oxfordian of shallow-marine shoreface and Oxfordian-Kimmeridgian shallow-water delta successions, respectively. The lower ichnodiversity and ichnodisparity associated with the Oxfordian-Kimmeridgian deltaic intervals represents a decrease in the exploitation of under-used ecospace, due to unfavourable environmental conditions rather than an expression of evolutionary radiation.

中文翻译：

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侏罗纪浅至边缘海相沉积物的地质分析：以印度西部瓦加德高地为例

摘要 世界不同大陆广泛报道了浅层到边缘海洋（三角洲）环境的侏罗纪沉积物。这项研究显示了浅海和边缘海洋条件下动物沉积物行为的相互关系，暗示了对可能的鱼类差异的解释。Kachchh Wagad 高地的 Washtawa Dome 和 Adhoi 背斜出露的侏罗纪层序包括约 341 m 厚的层序，分为两个地层——下Washtawa 和上Wagad 砂岩。八个稀疏到高度生物扰动的沉积单元显示了来自 15 个鱼属的 23 种可识别的鱼种，代表了可广泛归因于 Skolithos 和 Cruziana 地层相的五个鱼形组合，并在浅海浅滩岸面和三角洲沉积相中发育。相对频率统计数据揭示了石英砂岩中多毛类优先产生的喂食结构占主导地位。这些结构代表了亚水平、亚垂直和复杂的洞穴，分别展示了浅海岸面卡洛维安-牛津阶和牛津阶-金默里阶浅水三角洲序列的十二类和六类建筑设计。由于不利的环境条件而不是进化辐射的表达，与牛津阶-基默里吉阶三角洲区间相关的较低的物种多样性和物种差异代表了未充分利用的生态空间的开发减少。这些结构代表了亚水平、亚垂直和复杂的洞穴，分别展示了浅海岸面卡洛维安-牛津阶和牛津阶-金默里阶浅水三角洲序列的十二类和六类建筑设计。由于不利的环境条件而不是进化辐射的表达，与牛津阶-基默里吉阶三角洲区间相关的较低的物种多样性和物种差异代表了未充分利用的生态空间的开发减少。这些结构代表了亚水平、亚垂直和复杂的洞穴，分别展示了浅海岸面卡洛维安-牛津阶和牛津阶-金默里阶浅水三角洲序列的十二类和六类建筑设计。由于不利的环境条件而不是进化辐射的表达，与牛津阶-基默里吉阶三角洲区间相关的较低的物种多样性和物种差异代表了未充分利用的生态空间的开发减少。