Welcome to the OA Earth-prints Repository!

A digital low power pulse compressed ionosonde was developed at the Istituto Nazionale di Geofisica e Vulcanologia (INGV), Rome, Italy. The aim of this Advanced Ionospheric Sounder, AIS-INGV, is to reduce the transmitted power and, consequently, weight, size, power consumption and hardware complexity. To compensate the power reduction the most advanced HF radar techniques such as the pulse compression and a phase coherent integration are used. The ionosonde is completely programmable and a PC supports the data acquisition, control, storage and on-line processing. The first prototype was installed at Gibilmanna Ionospheric Observatory (Sicily), an interesting location in the center of Mediterranean area. The new ionosonde will contribute to ionospheric database and real time knowledge of South European ionospheric conditions for space weather applications. In this work the first results (ionograms and autoscaled characteristics) are presented and briefly discussed.

A new digital ionosonde called AIS-INGV (Advanced Ionospheric Sounder) was designed both for research and for routine service of HF radio wave propagation forecast. Nearly the entire system was developed in the Laboratorio di Geofisica Ambientale at the Istituto Nazionale di Geofisica e Vulcanologia (INGV), Rome. It exploits advanced techniques for signal analysis, recent technological devices and PC resources. This paper describes design concepts and performance of the new ionosonde.

The Italian Ionospheric Antarctic Observatory of Terra Nova Bay (74.70S, 164.11E) was recently equipped with the AIS-INGV ionosonde developed at the Istituto Nazionale di Geofisica e Vulcanologia (INGV), Rome, (Italy). This paper aims to describe briefly which are the main characteristics of the instrument and show the good quality and reliability of the recorded ionograms.

The ionosonde is a system which exploits the radar technique: it applies electromagnetic waves with variable frequency in the HF band to measure the ionospheric layers electron density, height and other parameters. This paper is a technical report on the new digital ionosonde (AIS-INGV), which was designed both for research purposes and for the routine service of the HF radiowave propagation forecast. It has been developed almost completely within the Laboratorio di Geofisica Ambientale (LGA) at the Istituto Nazionale di Geofisica e Vulcanologia (INGV). It exploits advanced techniques for the signal analysis, recent technological devices and PC resources. The report is divided into two parts; the first is a general description of the design development, the second is a more detailed description of the blocks and circuits actually built and tested, directed to a specialist reader.

www.earth-prints.org aims to satisfy the increasing demand of fast, up-to-date, easy-accessible, and free-of-charge sources of information in all branches of Geosciences. It allows earth scientists to deposit electronic documents into its collections and to index them by subjects and keywords. Earth-prints provides a time-stamp to all deposited materials to insure precedence rights to original ideas and scientific results. It deals with copyright issues through Creative Common standards that offer a wide variety of licenses. All deposited material is made immediately available to the public. Subscribers will be sent a daily newsletter according to the topics they have signed in. The archive has a three-level hierarchical structure. The top level includes Atmosphere, Cryosphere, Hydrosphere, Solid Earth, and General. It then branches into several disciplines within the other two levels. Different collections take in different kinds of material, such as pre-prints, oral presentations, extended abstracts, published papers, conference papers, books and book chapters, posters, and Web products and databases. Earth-Prints main language is English but it accepts documents in other languages also, giving visibility to data and studies at local scale that are indeed of general interests. An abstract in English is always required. We will present a virtual tour into the many features of Earth-prints to provide all its potential users with an easy acquaintance of the system and make them explore its capabilities. Although the archive is based on latest information technology it requires no specific knowledge to be used because it manages all procedures for access, navigation, upload of documents and information retrieval through a user-friendly interface. What is the limit of open archive development? We think that the one and only limit of open archives is the eagerness of its users to share information and knowledge.

We set up a computational tool to numerically model static and quasi-static deformation generated by faulting sources embedded in plane or spherical domains. We use a Finite Element (FE) approach to automatically implement arbitrary faulting sources and calculate displacement and stress fields induced by slip on the fault. The package makes use of the capabilities of CalculiX, a non commercial FE software designed to solve field problems (see for details), and is freely distributed by request.

This book contains the proceedings of the 1st WSEAS International Conference on Environmental and Geological Science and Engineering (EG'08) which was held in Malta, September 11-13, 2008. This conference aims to disseminate the latest research and applications in Renewable Energy, Mineral Resources, Natural Hazards and Risks, Environmental Impact Assessment, Urban and Regional Planning Issues, Remote Sensing and GIS, and other relevant topics and applications. The friendliness and openness of the WSEAS conferences, adds to their ability to grow by constantly attracting young researchers. The WSEAS Conferences attract a large number of well-established and leading researchers in various areas of Science and Engineering as you can see from http://www.wseas.org/reports. Your feedback encourages the society to go ahead as you can see in http://www.worldses.org/feedback.htm The contents of this Book are also published in the CD-ROM Proceedings of the Conference. Both will be sent to the WSEAS collaborating indices after the conference: www.worldses.org/indexes In addition, papers of this book are permanently available to all the scientific community via the WSEAS E-Library. Expanded and enhanced versions of papers published in this conference proceedings are also going to be considered for possible publication in one of the WSEAS journals that participate in the major International Scientific Indices (Elsevier, Scopus, EI, ACM, Compendex, INSPEC, CSA .... see: www.worldses.org/indexes) these papers must be of high-quality (break-through work) and a new round of a very strict review will follow. (No additional fee will be required for the publication of the extended version in a journal). WSEAS has also collaboration with several other international publishers and all these excellent papers of this volume could be further improved, could be extended and could be enhanced for possible additional evaluation in one of the editions of these international publishers. Finally, we cordially thank all the people of WSEAS for their efforts to maintain the high scientific level of conferences, proceedings and journals.

This study presents magnetic anomaly data from a new high-resolution, low-altitude helicopter-borne magnetic survey recently collected on and offshore Tenerife in the Canary Archipelago. The Italian Istituto Nazionale di Geofisica e Vulcanologia (INGV) in collaboration with the Museo Nacional de Ciencias Naturales of the CSIC of Spain conducted the survey in 2006. The data for Tenerife and surrounding marine areas were processed into digital total intensity magnetic anomalies for geomagnetic epoch 2006.4. Relative to previously available higher altitude magnetic survey data, the new survey mapped higher resolution anomalies with significantly improved spatial details, especially over the Las Cañadas caldera and Teide-Pico Viejo complex in the central part of the island. A good correlation is evident between known structural geology and the magnetic anomalies, where the new shorter wavelength anomalies facilitate more detailed and comprehensive geologic interpretations.

We present a new seismotomography investigation providing a 3-D overall model of Vp, Vs and Vp/ Vs for Mt. Etna, the largest and most active volcano in Europe. We estimated and jointly evaluated P-and S-wave velocity patterns together with the Vp/Vs ratio, particularly useful to discriminate the presence of groundwater, gas, and melts and thus very precious for volcano investigations. We applied the LOTOS software to ~ 4600 crustal earthquakes that occurred in the Etnean area during the last 26 years, the longest time-interval ever analysed for Mt. Etna. This wide dataset has allowed us to characterize the volcano velocity structure getting over possible singularities due to specific eruptive phases. Our results further refined the high velocity body widely recognized in the southeastern sector of Mt. Etna by furnishing new clues on the possible former magma pathways. Moreover, the obtained 3D seismic velocity model depicted new anomalies revealing the presence of: (i) two shallow underground aquifers in the northern Etnean sector; (ii) a volume of strongly fractured rocks filled of fluids along the eastern flank; (iii) a quite deep region of probable fluid accumulation apparently not linked to the volcanic activity in the western sector. Seismic tomography based on arrival times of the P-and S-waves from local earthquakes is a powerful tool actively used for studying volcanic systems. For several volcanoes around the world, tomography allowed to successfully reconstruct the shallow-depth volcanic structure (see e.g., Refs. 1-4). Tomographic analyses have furnished, in particular, accurate pictures of the feeding systems and very precious constraints for modelling the volcanic processes also highlighting that each volcano has some peculiar features that makes it unique. In the last decades, tomographic studies have strongly benefited from the strengthening of seismic networks and computational progresses that, particularly for volcanic regions, allowed to carefully reconstruct 3D velocity models by furnishing P-and S-wave velocities and the Vp/Vs ratio, a key parameter to discriminate the presence of groundwater, gas, and melts (Refs. 5-7 , among others). On these grounds, in the present study we collected data from more than 4600 earthquakes recorded between 1997 and 2022 in order to perform a new tomographic inversion of Mt. Etna (South Italy) by applying the software LOTOS 8. Mt. Etna is the largest and most active volcano in Europe 9. It is a composite strato-volcano rising 3300 m above the sea level in eastern Sicily (Fig. 1). Mt. Etna is located at the intersection between several major structural units, where the Apennine-Maghrebian thrust belt, the Hyblean Plateau of the Africa foreland and extensional structures on the western side of the Ionian basin coexist (Fig. 1). Its activity primarily consists of nearly continuous degassing from summit craters, strombolian phases of highly variable intensity, and frequent basaltic lava flows, representing a main source of volcanic hazard in the area. Moreover, flank eruptions during which the magma bypasses the central plumbing system, intrudes as dikes and erupts along the volcano flanks, periodically occur. This kind of event produces a massive deformation affecting the entire morphology of the edifice (e.g., Refs. 10-12). In particular, in the last decade it has experienced a significant increase in eruption frequency together with the development of some of the most energetic paroxysmal sequences recorded at Mt. Etna in recent times 13. These include the three-year-long sequence of lava fountaining occurred between 2011 and 2013 14 and the very recent sequence of eruptions that took place between December 2020 and February 2022 15. Moreover, also during the writing of this paper, some episodes of explosions with ash emissions were recorded.

Active normal faults and fault systems potentially responsible for earthquakes with Magnitude up to 7 have been detected in the central Apennines since the 90s of the last century. Strong historical earthquakes have been associated to some active faults by means of paleoseismological analysis or by the comparison between the damage distribution and the fault geometry. On the other hand, several faults showing evidence of Late Quaternary activity cannot be related to high-magnitude historical earthquakes and are therefore defined as silent. The level of hazard associated to these silent faults is commonly considered as high. Within this light, the fault affecting the south-western slope of Mt. Morrone, in the Abruzzi Apennines, can certainly be considered as silent. Indeed, this tectonic structure, made of two parallel, northwest-southeast trending fault segments, is considered as potentially responsible for M ≥ 6.5 earthquakes, but its last activation probably occurred about 1,800 years ago, in the 2nd century AD. Geological and geomorphological surveys have been performed along the Mt. Morrone south-western slope in order to achieve data useful for the definition of (i) the kinematics and (ii) the slip rate of the mentioned fault system. Our analyses allowed us to confirm that this tectonic structure is characterized by a mainly normal kinematics with a minor left-lateral oblique component, fitting an about N 20° trending extensional deformation. The slip rate of the westernmost fault segment has been estimated through the offset of three orders of alluvial fan deposits attributed to the late Pleistocene by means of radiocarbon dating and tephrochronological age determinations. The slip rate estimate ranges between 0.27 and 0.36 mm/yr. The lack of displaced deposits in the footwall of the fault has hindered the estimation of the slip rate related to the eastern fault segment. The geometry of the two fault segments allowed us to hypothesize that they probably represents the splaying at surface of the same deep-seated fault. Therefore, assuming an ditribution of the slip between the two fault segments, a total slip rate for the Mt. Morrone fault system ranging between 0.54 and 0.72 mm/yr may be defined. Moreover, our observations allowed us to confirm that the maximum expected magnitude of an earthquake which may originate along this ~21,5 km-long fault system, according to Wells and Coppersmith (1994), is ~ 6.6.

Carbon dioxide is a key gas to monitor at volcanoes because its concentration and isotopic signature can indicate changes to magma supply and degassing behavior prior to eruptions, yet carbon isotopic fluctuations at volcanic summits are not well constrained. Here we present δ 13 C results measured from plume samples collected at Stromboli volcano, Italy, by Uncrewed Aerial Systems (UAS). We found contrasting volcanic δ 13 C signatures in 2018 during quiescence (0.36 ± 0.59‰) versus 10 days before the 3 July 2019 paroxysm (5.01 ± 0.56‰). Prior to the eruption, an influx of CO 2-rich magma began degassing at deep levels (∼100 MPa) in an open-system fashion, causing strong isotopic fractionation and maintaining high CO 2 /S t ratios in the gas. This influx occurred between 10 days and several months prior to the event, meaning that isotopic changes in the gas could be detected weeks to months before unrest. Plain Language Summary Volcanoes produce gases which change composition depending on how active the volcano is. One of these gases, carbon dioxide, is known to change in proportion to other gases before an eruption occurs, but little is known about how the isotopes of carbon change leading up to an eruption. Using drones to reach the gaseous plume of Stromboli volcano, Italy, we have captured carbon dioxide both during an inactive phase in 2018 and during the lead-up to a highly explosive eruption called a paroxysm in 2019. There is a stark difference in the carbon isotopes measured 10 days before the 3 July 2019 paroxysm as opposed to those measured in 2018. This is caused by the arrival of CO 2-rich magma which progressively degassed, leading to lighter carbon isotopes in the residual magma over time. This process could have started anywhere from 10 days to several months before the paroxysm. This provides a warning signal which can be detected weeks to months before an active period begins.