This paper evaluates previously proposed diagnostic criteria that can be used to determine whether or not there is active migration of the opal-A to opal-CT transition zone (TZ_A/CT). The criteria are based on the interpretation of 2D and 3D seismic surveys and are therefore geometrical. They involve an assessment of the relationship of the TZ_A/CT with polygonal fault systems, differential compaction structures and tectonic folds. The most robust evidence for an inactive ‘reaction front’ between opal-A and opal-CT bearing sediments is the discordance of the TZ_A/CT relative to present-day isotherms. Any of these may be persuasive as diagnostic criteria for the upward arrest of the diagenetic transformation at a regional scale, but actual truncation of the TZ_A/CT at the modern seabed is definitive for arrested diagenesis. This study argues that diagenetic assessment based solely on a single criterion independently is not reliable as an indicator for the current state of a silica transition. As a conclusion, the analysed seismic/structural criteria should be synthesised to provide a more credible interpretation for silica diagenesis. The use of modern 2D and 3D seismic data for the reconstruction of the diagenetic history of opaline silica bearing sediments offers a new approach to the study of silica diagenesis at a regional scale.

中文翻译：

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停滞与活跃的二氧化硅成岩反应边界——地震诊断标准的回顾

本文评估了先前提出的诊断标准，该标准可用于确定蛋白石 A 是否存在向蛋白石 CT 过渡区 (TZ _A/CT ) 的主动迁移。该标准基于 2D 和 3D 地震勘测的解释，因此是几何的。它们涉及评估 TZ _A/CT与多边形断层系统、差异压实结构和构造褶皱的关系。蛋白石-A 和蛋白石-CT 沉积物之间不活跃的“反应前沿”的最有力证据是 TZ _A/CT相对于当今等温线的不一致。这些中的任何一个都可能具有说服力，作为在区域尺度上阻止成岩转化的诊断标准，但实际截断 TZ_{现代海床的A/CT}是阻止成岩作用的决定性因素。该研究认为，单独基于单一标准的成岩作用评估作为二氧化硅转变当前状态的指标是不可靠的。作为结论，应综合分析所分析的地震/结构标准，以便为二氧化硅成岩作用提供更可信的解释。使用现代 2D 和 3D 地震数据来重建含乳白色二氧化硅的沉积物的成岩历史，为在区域尺度上研究二氧化硅成岩作用提供了一种新方法。