2026/07/04 by F. Fanti, L. Consorti, M. Muscioni +8 · 1 voice
Earth and Planetary Sciences · #Paleontology and Evolutionary Biology #Paleontology and Stratigraphy of Fossils #Geological formations and processes
paper · doi:10.1016/j.gloplacha.2026.105589
Konservat-Lagerstätten provide exceptional records of past ecosystems, yet the environmental and climatic processes governing their formation in extreme climatic regimes remain a significant, unresolved conundrum. Here we present a novel, process-based mechanism for the Villaggio del Pescatore Konservat-Lagerstätte (northeastern Italy; Late Cretaceous, 80 Ma), which preserves a diverse terrestrial and aquatic biota. Integrating high resolution synchrotron micro-analyses, bulk geochemistry, detailed taphonomy and palaeoclimate simulations we identify a dynamic, monsoon-paced tidal flat ecosystem within a carbonate coastal margin. Field and core records comprise metrescale packages of laterally persistent light–dark laminae; microstratigraphic, spectral and statistical analyses indicate a semidiurnal tidal regime with neap–spring modulation. MicroXRF/XRD mapping reveals that individual microlaminae within couplets share the same elemental inventory refuting a seasonal varve origin. Laminae chronometry, tied to the tidal interpretation, constrains net accumulation of the fossil bearing rhythmites to decadal (~40 year) timescales. Geochemical proxies record alternating terrigenous rich, high TOC intervals and drier, better oxygenated intervals. Palaeoclimate model ensembles diagnose a vigorous, summer dominated monsoon domain at ~29° N under greenhouse boundary conditions. We document that episodic monsoon enhanced flood and tropical cyclone pulses delivered sediment, nutrients, carcasses and plant debris to a microbially active, carbonate tidal flat; microbial mats rapidly stabilised and promoted early cementation, enabling exceptional soft tissue preservation. We propose a genetic model in which monsoon–cyclone forcing, tidal trapping and microbial sealing combine to produce decadal, daily resolved vertebrate Lagerstätten in greenhouse settings, offering predictive targets for similar deposits and deep time analogues for modern coastal change.