_applied_  
_sciences_  
_Article_  
Machine Learning in Discriminating Active Volcanoes of the  
Hellenic Volcanic Arc  
**[PERSON] \({}^{\ast}\)\({}^{\copyright}\) and [PERSON] \({}^{\copyright}\)**  
HUMAIN-Lab, Department of Computer Science, International Hellenic University, 65404 Kavala, Greece; [EMAIL_ADDRESS]  
\({}^{\star}\) Correspondence: [EMAIL_ADDRESS]; Tel. : +30-6945260121  
**Abstract** Identifying the provenance of volcanic rocks can be essential for improving geological maps in the field of geology and providing a tool for the geochemical fingerprinting of ancient artifacts like millstones and anchors in the field of geoarchaeology. This study examines a new approach to this problem by using machine learning algorithms (MLAs). In order to discriminate the four active volcanic regions of the Hellenic Volcanic Arc (HVA) in Southern Greece, MLAs were trained with geochemical data of major elements, acquired from the GEOROC database, of the volcanic rocks of the Hellenic Volcanic Arc (HVA). Ten MLAs were trained with six variations of the same dataset of volcanic rock samples originating from the HVA. The experiments revealed that the Extreme Gradient Boost model achieved the best performance, reaching 93.07% accuracy. The model developed in the framework of this research was used to implement a cloud-based application which is publicly accessible at This application can be used to predict the provenance of a volcanic rock sample, within the area of the HVA, based on its geochemical composition, easily obtained by using the X-ray fluorescence (QRF) technique. machine learning: Hellenic Volcanic Arc; geochemistry; geoarchaeology; geochemical fingerprinting  
**1. Introduction**  
The Hellenic Volcanic Arc (HVA) in Southern Greece consists of four volcanic regions (Figure 1), namely the Methana region, which includes Methana, Aigina, and Poros in the west; the Melos region, consisting of Melos, Antimelos, and Kimolos in the southwest; the Santorini region, consisting of Santorini, Kolumbus, and Christianoi in the southeast; and the Nisyros region consisting of Nisyros, Giali, and Pergous in the east. All active volcanoes of the HVA were formed by a converging tectonic setting, producing Island Arc Basalts (IABs) belonging to the calc-alkaline and high-K calc-alkaline series. The first activity took place during the Pliocene (5 m.y.) and continues to the present day [1, 2, 3]. The extent of the HVA is well-mapped on the surface [1], but little is known about its extent under the seafloor. A large part of the HVA is buried under the sediments of the Southern Aegean Sea. Future deep-sea drilling for mineral prospecting will provide rock samples to produce more precise geological borders for the HVA. In order for these rock samples to be used for mapping, they have to be correlated to one of the four active volcanic regions. Furthermore, volcanic rocks from the HVA have been used to produce artifacts like millstones and anchors from prehistoric times. These artifacts can be found scattered all around the Mediterranean. One of the questions about these artifacts in archaeology is the source of the original material. By answering that question, ancient trade routes can be revealed. One obvious approach used to correlate volcanic rocks and fingerprint ancient artifacts is to use the geochemistry of these rocks to identify their provenance. By studying the binary K\({}_{2}\)O versus SiO\({}_{2}\) diagram [4] of the HVA compiled from 1500 data samples (Figure 2) [2], major overlaps of the data points can be seen. It is obvious that no discrimination between the volcanic regions of the HVA can be established based on this diagram. Figure 1: The Hellenic Volcanic Arc: 1. Methane group, 2. Melos group, 3. Santorini group, and 4. Nisyros group. Figure 2: K\({}_{2}\)O versus silica classification diagrams [4] for (**a**) Nisyros group (**b**) Santorini group (**c**) Melos group and (**d**) Methane group.