Abstract An integrated study of micro- and nannoplankton distribution, O and C isotopes and palaeomagnetic record of nine Carpathian sections provided a key interpretation tool to characterize the Jurassic–Cretaceous (J/K) boundary transition. Biostratigraphy supported by saccocomids, radiolarians, calpionellids, dinoflagellates and nannofossils helped to distinguish biostratigraphic zones which could have been correlated both with stable isotopes and with magnetostratigraphy. The Alpina Event (lorica size change) accompanied by Nannoconus wintereri and N. steinmannii minor FO's designates the J/K boundary. Sedimentary model in N Mediterranean Tethys margin consists of elevated blocks with slow (1–2 mm/ka) Rosso Ammonitico carbonate sedimentation separated by dysoxic depressions. Tectonic instability has been indicated by Upper Jurassic fluxoturbidites. Late early Tithonian (M21n to M20r) saccocomid abundance increases with positive δ18O isotope ratios, similar excursion between M20n and M19r accompanied late Tithonian crassicollarian boom. The δ13C variation (>0.2‰) confronted with microplankton quantity variations: positive excursion occurred both during early Tithonian Saccocoma sp., and during late Tithonian calpionellid and nannoconid blooms. Higher up in the Berriasian “Maiolica” sequence, lighter δ13C values prevailed. During late Tithonian (Praetintinnopsella-to earliest Crassicollaria zones; M20n1n to M19r), Saccocoma microfacies has been substituted by a calpionellid one. Reorganization of Tethyan oceanic currents during opening of the Hispanic corridor started planktonic carbonate particle „rain“ resulting in the Maiolica facies dominance. Sedimentary rate raised ten times. Calpionella alpina lorica size change event was synchronneous with FO's of Nannoconus wintereri and N. steinmannii minor and with negative δ18O trend of latest Tithonian (Colomi Subzone) warming. Expressiveness of eccentricity and obliquity cycles indicates climatic optimum conditions.

中文翻译：

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喀尔巴阡沉积层序中侏罗纪-白垩纪边界记录

摘要 对九个喀尔巴阡剖面的微浮游生物分布、O 和 C 同位素以及古地磁记录的综合研究为描述侏罗纪-白垩纪 (J/K) 边界过渡提供了关键的解释工具。由囊状动物、放射虫、calpionellids、甲藻和纳米化石支持的生物地层学有助于区分可能与稳定同位素和磁地层学相关的生物地层区。Alpina 事件（lorica 大小变化）伴随着 Nannoconus Wintereri 和 N. steinmannii minor FO's 指定了 J/K 边界。北地中海特提斯边缘的沉积模型由缓慢 (1–2 mm/ka) Rosso Ammonitico 碳酸盐沉积的高架块组成，被缺氧洼地隔开。上侏罗统流浊积岩表明构造不稳定性。提通阶晚期（M21n 到 M20r）囊状体丰度随着 δ18O 同位素比的增加而增加，M20n 和 M19r 之间的类似偏移伴随着提通阶晚期跨领繁荣。δ13​​C 变化 (>0.2‰) 面临着微浮游生物数量的变化：在早期 Tithonian Saccocoma sp. 和晚期 Tithonian calpionellid 和 nannoconid 绽放期间都发生了正偏移。在 Berriaasian “Maiolica”序列的更高处，较轻的 δ13C 值占主导地位。在提通阶晚期（Praetintinnopsella 到最早的 Crasassicollaria 区；M20n1n 到 M19r），Saccocoma 微相已被 calpionellid 微相取代。在西班牙走廊开放期间，特提斯洋流的重组开始了浮游碳酸盐颗粒“雨”，导致 Maiolica 相占优势。沉积率提高了十倍。Calpionella alpina lorica 的大小变化事件与冬季南锥孢和 N. steinmannii minor 的 FO's 同步，并且与最新提通期（Colomi Subzone）变暖的负 δ18O 趋势同步。离心率和倾斜周期的表现力表明气候最佳条件。