The well-exposed Upper Kimmeridgian to Lower Tithonian sequences of the Boulonnais Region (Northern France) are revisited with an integrated litho-, bio- and chemostratigraphic study of the Cran du Noirda (CDN) and Pointe de la Crèche (PDC) sections. Three foraminiferal and two ostracods zones are identified and tied to the ammonite zones previously established in the Boulonnais. The Upper Kimmeridgian Pseudolamarckina pseudorjasanensis foraminifera Zone is of particular interest, as we establish that it may be recognized in very distant regions throughout the Subboreal, Boreal, and Arctic provinces. The comprehensive analysis of the TOC content and Rock Eval pyrolysis allows to underline the deposition of a Lower Tithonian Organic-Rich Interval (ORI) associated with the wheatleyensis – scitulus (p.p.) ammonite zones. Furthermore, the palaeoecological analysis of the identified foraminiferal assemblages suggests the occurrence of four dysoxic events during the Late Kimmeridgian to Early Tithonian. Foraminiferal assemblages with genera adapted to low-oxygen conditions are present in intervals with high values of δ¹³C_TOC. During the Late Kimmeridgian to Early Tithonian, organic-rich deposits are widespread across the Western European Archipelago and the Laurasian Seaway. The establishment of hypoxic conditions above the sea-floor was favoured by high marine productivity and stratification of the water column. Conversely, periods of low relative sea-level resulted in the redeposition of sediments from the margins into the basin, while water depth was insufficient to allow the development of reduced conditions.

通过对Cran du Noirda（CDN）和Pointe de laCrèche（PDC）断面的岩性，生物和化学地层学综合研究，重新研究了布隆奈地区（法国北部）的暴露良好的上Kimmeridgian到下Tithonian层序。确定了三个有孔虫区和两个成虫区，并将其与先前在Boulonnais中建立的亚mon石区绑定在一起。由于我们确定在上亚伯利亚省，北方省和北极省的非常遥远的地区都可以认识到上基默尼迪亚伪造假山毛孔菌区特别有意思。对TOC含量和岩石评估热解的综合分析可以突显与Wheatleyensis – scitulus相关的较低的Tithonian有机富集层期（ORI）的沉积。（pp）炸药区。此外，对已确定的有孔虫类群的古生态分析表明，在基米底尔吉安晚期至提通盆地早期发生了四次低氧事件。与属有孔虫组合适于低氧条件存在于与δ的高值的时间间隔¹³ Ç _TOC。在Kimmeridgian晚期至Tithonian早期，富含有机物的沉积物遍布西欧群岛和Laurasian Seaway。海洋生产力高和水柱分层有利于在海底之上建立低氧条件。相反，相对海平面低的时期导致沉积物从边缘重新沉积到盆地中，而水深不足以使条件降低的发展。