The Cretaceous/Palaeogene Boundary (KPgB) represents one of the five major mass extinctions in Earth's history, and determining the nature of associated environmental change and biotic recovery is critical for understanding the history of life on our planet. To explore that, we examined the distributions of selected biomarkers (n-alkanes, acyclic isoprenoids, steranes and hopanes), organic and carbonate δ¹³C values, total organic carbon contents and major and trace elements in a distal section spanning the KPgB (Agost, SE Spain). The studied Agost section is an ~32 cm-thick bathyal sequence of marlstones, clays and marly limestones, and high sedimentation rates allow high (cm) resolution analysis. These analyses exhibit sample-to-sample variability, but there are few significant differences between pre- and post-KPgB biomarker assemblages, suggesting a rapid recovery of the non-fossilizing phytoplankton community after the KPgB. Despite the persistence of life, the organic matter assemblage is rather variable through the first 10 kyr after the impact event. This interval is associated with changing terrigenous and petrogenic inputs as well as varying redox conditions as reflected by the enrichment factor of uranium (U_EF) vs that of molybdenum (Mo_EF) as well as biomarker indices (gammacerane and homohopane indices). Moreover, sterane distributions do differ between pre- and post-KPgB sediments. Thus, the KPgB impact did affect environmental conditions and non-fossilizing algal and bacterial communities even in distal sites, but these organisms appear to have rapidly recovered, within 10 kyr after the KPgB.

白垩纪/古近纪边界（KPgB）代表了地球历史上五个主要的物种灭绝事件之一，确定相关的环境变化和生物恢复的性质对于理解我们星球上的生命历史至关重要。为了探索，我们检查选定生物标志物的分布（Ñ烷烃，无环类异戊二烯，甾烷和藿烷），有机和碳酸盐δ ¹³C值，总有机碳含量以及跨越KPgB（Agost，SE西班牙）的远端区域中的主要和微量元素。研究的Agost剖面是厚约32厘米的深水层层序的泥灰岩，粘土和灰泥灰岩，高沉积速率可以进行高分辨率（cm）的分析。这些分析显示出样品间的变异性，但在KPgB之前和之后的生物标志物组合之间几乎没有显着差异，这表明在KPgB之后非僵化的浮游植物群落迅速恢复。尽管生命持续存在，但有机物的组合在撞击事件发生后的第一个10年内变化很大。这个间隔与陆源和成岩输入的变化以及氧化还原条件的变化有关，这反映在铀的富集因子上（U _EF）与钼（Mo _EF）以及生物标志物指数（γ-角ane烷和高庚烷指数）相比。此外，前KPgB沉积物和后KPgB沉积物的甾烷分布确实不同。因此，KPgB的影响确实影响了环境条件以及甚至在远端部位的非僵化藻类和细菌群落，但是这些生物似乎在KPgB之后的10年内迅速恢复。