Jose Kling

Long‐term tephrostratigraphies of volcanic islands such as the Azores are often limited to young and incomplete subaerial records. Here, we present a Pleistocene‐Holocene marine tephra archive around the eastern islands of the Azores based on 22 marine gravity cores. We provide a new extensive data set comprising major element glass compositions of 350 marine tephra layers and 26 tephra samples collected from subaerial outcrops on São Miguel Island. The marine tephra record is dominated by trachytic glass compositions with lesser amounts of trachy‐basaltic/basaltic materials. We categorize the marine deposits into four facies: primary fall (F1), primary flow (F2), eruption‐related secondary flow (F3), and non‐eruption‐related secondary flow deposits (F4). Cores collected close to the islands contain a high proportion (>50%) of volcaniclastic material deposited during secondary processes. Using machine‐learning algorithms, we assign potential volcanic sources to individual tephra layers. Furthermore, our spatial characterization of primary/secondary deposits demonstrates the importance of carefully selecting core locations during sea‐going campaigns, as the preservation and distribution of primary and reworked tephras considerably differ depending on several factors (e.g., on paleo‐wind directions, island topography, seafloor bathymetry, and distance from source volcanoes). We also report the occurrence of mafic primary fall tephras tens to hundreds kilometers away from the closest island, indicating a potential hazard from mafic Plinian eruptions in the Azores. This study aims to improve the estimation of the eruptive frequency of the archipelago and opens new pathways for more detailed studies concerning long‐term volcanic cyclicity in the region.

A variety of subaerial and submarine events, including mass‐wasting and volcanism, can generate sediment gravity flows and fallout deposits that are preserved in deep‐water stratigraphic records. This study examines whether event beds with differing depositional and transport histories exhibit distinct thickness‐frequency distributions. Analyzing over 4,500 event beds from seven drilling sites near Montserrat, the Izu Arc, the Kyushu‐Palau Ridge, and Gran Canaria, the analyses explore variations in event‐bed characteristics across different climatic periods, volcanic stages, and geomorphological settings. Statistical methods include characterizing thickness‐frequency distributions and assessing subset similarity using t ‐tests and smoothed distribution patterns. The data‐driven results indicate discernible differences where dominant geological processes vary. For example, volcanic growth stages at the Kyushu–Palau Ridge produced thicker, coarser, and more frequent event beds compared with quiescent stages. Similarly, beds from the north slope of Gran Canaria—where submarine canyons enhanced sediment delivery—were nearly twice as thick as those from the south. In contrast, indistinguishable characteristics between the rear and frontal Izu Arc subsets after 3 Ma are attributed to the development of an extensional zone supplying material to both arc sides. Comparable distributions were also observed within intervals with minimal geological differences. The reliability of this analytical approach depends on high‐quality sediment recovery, as drilling‐related disturbances may obscure primary depositional signals. Beyond stratigraphic characterization, the method shows broader potential for identifying the provenance of volcanic glass shards through geochemical comparisons and for evaluating the statistical compatibility of data sets from neighboring sites, ensuring sufficient sample size for robust integrated analyses.

This toolbox implements various tools for working with simple, non-marked, one dimensional point processes. The highlight of this toolbox is the new goodness-of-fit test developed for parametric models.