Abstract The stratigraphy of mercury (Hg) in sections of the Araripe Basin straddling the Aptian-Albian transition, encompassing the Romualdo, Ipubi, Crato and Barbalha (formerly Rio da Batateira)Formations showed positive excursions of Hg concentrations without correlation with organic carbon (C-org) contents. These incursions occurred during the deposition of the Barbalha Formation, which occurred in the Aptian under warm climate and high bio-productivity; in the Crato Formation, in the Albian, and also during the deposition of the Romualdo Formation. The Hg enrichments suggest external sources of Hg to the basin. The positive Hg excursion in the Ipubi Formation, unlike the others, was shown to be correlated with an increase in the deposition of C-org, suggesting internal processes as major river of Hg accumulation in sediments. The positive Hg excursions independent of C-org accumulation are concomitant to periods of intense volcanic activity in the Kerguelen Large Igneous Provinces (LIP). The excursion observed in the Ipubi Formation, however, seems associated with an event of anoxia, resulting in sediments rich in C-org, scavenging Hg from the water column. The Hg chemostratigraphy helps to understand of the paleoenvironmental changes in the Araripe basin, allowing understanding some of the drivers of such changes as the influence of volcanic activity and events of anoxia, as well as major biological crises.

中文翻译：

---

巴西东北部阿拉里佩盆地阿普蒂安-阿尔比亚过渡带中，作为火山驱动环境变化的代表的汞化学地层学

摘要 Araripe 盆地横跨 Aptian-Albian 过渡带，包括 Romualdo、Ipubi、Crato 和 Barbalha（以前的 Rio da Batateira）地层的汞 (Hg) 地层显示汞浓度呈正偏移，与有机碳 (C -org) 内容。这些入侵发生在 Barbalha 组的沉积期间，该组发生在气候温暖、生物生产力高的 Aptian；在克拉托组、在阿尔比安以及在 Romualdo 组沉积期间。汞的富集表明盆地的外部汞来源。与其他地层不同，Ipubi 组中汞的正偏移与 C-org 沉积的增加有关，表明内部过程是沉积物中汞积累的主要河流。与 C-org 积累无关的汞正偏移伴随着凯尔盖朗大型火成岩省 (LIP) 的剧烈火山活动时期。然而，在 Ipubi 组中观察到的偏移似乎与缺氧事件有关，导致富含 C-org 的沉积物从水柱中清除汞。汞化学地层学有助于了解阿拉里佩盆地的古环境变化，从而了解火山活动和缺氧事件的影响以及重大生物危机等变化的一些驱动因素。导致沉积物中富含 C-org，从水柱中清除 Hg。汞化学地层学有助于了解阿拉里佩盆地的古环境变化，从而了解火山活动和缺氧事件的影响以及重大生物危机等变化的一些驱动因素。导致沉积物中富含 C-org，从水柱中清除 Hg。汞化学地层学有助于了解阿拉里佩盆地的古环境变化，从而了解火山活动和缺氧事件的影响以及重大生物危机等变化的一些驱动因素。