The stratigraphic evolution of the Guadagnolo Fm, developed on the transition between the Latium-Abruzzi Platform and the Umbria Sabina Basin (central Apennines), was studied through facies and stable isotope analysis. Calcareous nannofossil biostratigraphy allows to identify the Burdigalian-Langhian boundary, constraining the sections to the lower to middle Miocene. This interval consists of marly deposits forming the intermediate member of the formation dominated by sponge spicules, molluscs, bryozoans, benthic and planktonic foraminifers. This member is deposited in a distal outer ramp where the abundance of siliceous sponges has been attributed to the high seawater fertility coinciding with the Monterey event, enhanced by regional nutrient flux due to continental runoff and volcanism. The upper member is Serravallian and consists of bryozoan-dominated cross-bedded calcarenites deposited in a shallower environment of the outer ramp.

A positive carbon isotope excursion was correlated with the Monterey event recorded in the Central Apennines carbonate ramps and from ODP sites. Five carbon maxima belonging to the Monterey Carbon Isotope Excursion have been identified. Four carbon isotope peaks fall in the spongolitic member, one in the upper member. The Carbon Maxima recorded within the spongolitic member show an attenuate isotope excursion compared with the pelagic and the carbonate platforms record. The weaker signal is due to the fractionation effect of primary producers of the photic zone and to the sponge release of ¹²C-enriched CO₂ deriving from the oxidation of organic matter. Conversely, the largest positive carbon isotope excursion is recorded in the upper member, representative of a shallower environment, and it is due to the absence of sponges and the increased contribution of photosynthetic biota. The shoaling of the depositional environment is related to the global cooling recorded after 14 Ma, as evident also from the δ¹⁸O positive shift at the base of the upper member of the Guadagnolo Fm.

通过岩相和稳定同位素分析研究了在Latium-Abruzzi平台和Umbria Sabina盆地（中亚平宁山脉）之间过渡形成的Guadagnolo Fm的地层演化。钙质纳米化石生物地层学可以识别布尔迪加利安-朗吉安边界，将这些剖面限制在中新世的中低层。该间隔由形成岩层中间成员的马来沉积物组成，其中以海绵针，软体动物，苔藓虫，底栖和浮游有孔虫为主。该构件沉积在远处的外部斜坡上，那里大量的硅质海绵被归因于与蒙特里事件相吻合的高海水肥力，由于大陆径流和火山作用引起的区域养分通量增加了这种能力。

正碳同位素偏移与中亚平宁山脉碳酸盐岩坡道和ODP站点记录的蒙特雷事件有关。已经确定了五个属于蒙特雷碳同位素游览的碳最大值。四个碳同位素峰落在海绵岩中，一个在上部。与中上层和碳酸盐台地记录相比，海绵状岩中记录的最大碳极谱显示出同位素的衰减。较弱的信号归因于光合带主要生成者的分馏作用以及海绵中释放出的富含¹² C的CO ₂来自有机物的氧化。相反，最大的正碳同位素偏移记录在上部，代表着较浅的环境，这是由于没有海绵并且光合生物群的贡献增加。沉积环境的变浅涉及全球后14马冷却记录，如明显还从δ ¹⁸在Guadagnolo FM的上部构件的基座O正移位。