Volcano distribution and tectonics: A planetoidic perspective

ABSTRACT Volcanic activity is ultimately controlled by processes that take place many kilometers beneath the surface of a planet. The deeper processes are unlikely to reach the surface without some degree of modification at shallower levels. Nevertheless, traces of those deeper processes may still be found when examining the final products at the surface. In this work, it is shown that it is possible to gain insights concerning the integrated contribution of deep structures through the study of the spatial distribution of volcanic vents at the surface. The method here described relies on the systematic use of increasing smoothing factors in Gaussian kernel estimations. The sequences of probability density functions thus generated are equivalent to images obtained with an increasing wavelength, which therefore have the power to penetrate deeper below the surface. Although the resolution of this method is much smaller than the resolution provided by seismic or other geophysical surveys, it has the advantages of ease of implementation, extremely low cost, and remote application. Thus, the reported method has great value as a first-order exploration tool to investigate the deep structure of a planet, and it can make important contributions to our understanding of the volcano-tectonic relationship, not only on Earth, but also across the various bodies of the solar system where volcanic activity has been documented.

Urban water supply infrastructure in Grudziądz (northern Poland): from the Middle Ages to the pre-modern times

This article presents the history of the water supply system in Grudziądz (Poland) over the centuries, from the Middle Ages to the end of the nineteenth century. The location of Grudziądz on the high escarpment of the Vistula River made it difficult to supply water to the town. The innovative technical facilities, such as a water-work and water supply tower had to be constructed because the gravitational waterworks could not be applied. The basis for the research was the analysis of historical sources. In this study, non-invasive methods were used (aerial prospection, LiDAR scanning and geophysical surveys with Ground Penetrating Radar), since the hydrotechnical objects are located in a functioning urban space and no excavations could be carried out. The research included: (i) the measurements, exploration and preparation of photo-documentation of the water tower, (ii) providing a digital model of the tower, (iii) finding the tunnel inside the tower, and (iv) attempting to locate the tunnel's course outside the tower.

First considerations on post processing kinematic GNSS data during a geophysical oceanographic cruise

<p class="Abstract">Differential GNSS positioning on vessels is of considerable interest in various fields of application as navigation aids, precision positioning for geophysical surveys or sampling purposes especially when high resolution bathymetric surveys are conducted. However ship positioning must be considered a kinematic survey with all the associated problems. The possibility of using high-precision differential GNSS receivers in navigation is of increasing interest, also due to the very recent availability of low-cost differential receivers that may soon replace classic navigation ones based on the less accurate point positioning technique. The availability of greater plano-altimetric accuracy, however, requires an increasingly better understanding of planimetric and altimetric reference systems. In particular, the results allow preliminary considerations on the congruence between terrestrial reference systems (which the GNSS survey can easily refer to) and marine reference systems (connected to National Tidegauge Network). In spite of the fluctuations due to the physiological continuous variation of the ship's attitude, GNSS plot faithfully followed the trend of the tidal variations and highlighted the shifts between GNSS plot and the tide gauges due to the different materialization of the relative reference systems.</p><p class="Abstract"><span lang="EN-US"><br /></span></p>

Significance of petroleum seepages in hydrocarbon exploration-case study of Khourian Desert, Central Iran

Hydrocarbon exploration has long been based on such costly and time-intensive methods as geophysical surveys, geological studies, and drilling. In recent years, however, researchers have started to consider such inexpensive alternatives as surface geochemistry for hydrocarbon exploration. Some 100 years ago, the leakage of hydrocarbons onto the surface in the form of micro- and macro-seepages motivated researchers toward drilling a well in the Khourian Desert in the south of Semnan Province, Iran. Upon drilling the well, researchers found evidences of non-released (free) hydrocarbons. These findings drove further study of the area using surface geochemistry while considering the nearby hydrocarbon accumulation in Qom Formation. Conventional and indirect surface geochemical methods provide an insight into the relationship between surface and subsurface hydrocarbons. In the present work, the results of the Rock–Eval pyrolysis showed total organic carbon (TOC) values in the range of 0.31–4.13 wt.% and S1 peaks between 0.07 and 27.35. Sulfur isotope analysis showed a sulfur isotopic value of −0.4. The study of hydrocarbon-oxidizing bacteria showed the presence of bacterial colonies in MSM at 1.22 × 106 cfu/g of soil sample. We further investigated surface changes due to the presence of free hydrocarbons and pH variations (4.9–8) resulted from the changes in the concentrations of calcium carbonate and iron. According to the results and given the presence of organic sulfur in the samples, the occurrence of Gach-i-turush and alike phenomena was proposed in this area. The results of geo-microbial prospecting method, surface secondary changes, and sulfur isotope studies were well in agreement with the characteristics of the existing hydrocarbon reserves in this area. Surface geochemical surveys can precede other geochemical and geophysical surveys to identify surface anomalies and hence focus on more probable locales of hydrocarbon accumulation in the Khourian Desert, central Iran.

Opening a New Frontier in the Study of Neolithic Settlement Patterns of Eastern Thessaly, Greece

The Innovative Geophysical Approaches for the Study of Early Agricultural Villages of Neolithic Thessaly (ARISTEIA-IGEAN) Project made an extensive use of geospatial technologies in the study of the natural environment and social dynamics of Neolithic settlements within the coastal region of eastern Thessaly, Greece. The goal of the project was to offer a broad and non-destructive remote sensing coverage of a number of Neolithic settlements to study habitation practices that were developed in various ecological niches and to document site-specific cultural and environmental characteristics. The methods and techniques used in the IGEAN project included satellite remote sensing, Remotely Piloted Aircraft Systems (RPAS), ground-based geophysical surveys exploring new generation prospection instrumentation, and soil analyses. The manifold research agenda proved to be effective for the detailed mapping of soils in which archaeological residues of past occupation reside. The full open-access geospatial data is served online at http://igean.ims.forth.gr/. The IGEAN project exposed a large degree of variation in the occupation of the landscape and the usage of space in both small and large settlements. The study was able to capture an integrated image of the habitation settings and highlight the large degree of divergence in the intra-site settlement patterns of these agrarian societies. The synthesis of the results opens up further research questions regarding early agricultural villages of Neolithic Thessaly.

Invasion, retaliation, concealment and silences at Dead Man’s Flat, South Australia: A consideration of the historical, archaeological and geophysical evidence of frontier conflict

This article presents the results of historical research, as well as archaeological and geophysical surveys, in order to explore a number of frontier conflict events at Dead Man’s Flat in South Australia (SA). The historical records reveal the cruelty and complexity of the period and expose the concealments, contradictions, euphemistic language, denials and silences that are typical of the Australian frontier. Further disparities are revealed in more recent commemorative efforts. Archaeological investigations in the study area provided an ‘absence of evidence’. Whilst the geophysical survey revealed that there are potential graves located on the flat, no interment was located in the area commemorated by local non- Indigenous community members. The combined results of this multi-method approach uncovered new dissonances, raised new questions and provided new exegeses about the frontier in this region. For traditional owners, the sum of the evidence reveals a history of invasion, killings and massacre, theft, deceit and cover-up – Dead Man’s Flat is, therefore, a place to be approached with deep respect in order to honour the experiences of their ancestors.

Resolving Dimensions: A Comparison Between ERT Imaging and 3D Modelling of the Barge Crowie, South Australia

Three-dimensional (3D) modelling is becoming a ubiquitous technology for the interpretation of cultural heritage objects. However most 3D models are based on geomatic data such as surveying, laser scanning or photogrammetry and therefore rely on the subject of the study being visible. This chapter presents the case study of Crowie, a submerged and partially buried barge wrecked near the town of Morgan in South Australia. Crowie was reconstructed using two alternative approaches; one based on a combination of historic photographs and computer graphics and the second based on geophysical data from electrical resistivity tomography (ERT). ERT has been rarely used for maritime archaeology despite providing 3D representation under challenging survey conditions, such as in shallow and turbid water. ERT was particularly successful on Crowie for mapping the external metal cladding, which was recognisable based on very low resistivity values. An alternative 3D model was created using historic photographs and dimensions for Crowie in combination with information from acoustic geophysical surveys. The excellent correspondence between these models demonstrates the efficacy of ERT in shallow maritime archaeology contexts.

Investigations at the Trypillia settlement near Hlybochok village in Cherkasy Oblast

The Trypillia settlement is located at the western edge of Hlybochok village (former Zvenyhorodka district of Cherkasy Oblast), at the plateau of the western bank of the Hirskyi Tikych River. According to the geophysical surveys, the settlement size reached 100 ha. Its dwellings were organized into two ellipses. The remains of two dwellings (ploshchadki) were excavated in 1994—1995. Ploshchadka No. 1 was located in the southern part of the external construction ellipse, while ploshchadka No. 2 was located in the second internal ellipse at the eastern part of the site. The remains of both houses had a rectangular shape and included several layers of burnt clay. Houses had fireplaces on the lower storey. The second house also included an elevation of rectangular shape with grinding stones. Living areas are associated with the upper storey of houses. The majority of materials, mainly kitchen and table pottery, were found between the layers of burnt clay. Kitchen pottery (6—7 %) is represented by conical bowls and pots with S-shaped profiles with poor ornamentation. Table pottery (92—93 %) is represented by ceramics ornamented with black monochromic painting. Nearly 45 % of pottery forms and 25 % of ornamentation schemes were reconstructed. Ceramic shapes are represented by bowls, goblets, biconical, spherical and conical vessels, amphorae, pear-shaped vessels, leads, craters, pots and binocular-shaped vessels. Anthropomorphic figurines were found in fragments. The Hlybochok settlement is referred to the late phase of Nebelivska group (the end of BII period) of the development of the Western Trypillia culture. The settlement is dated to the range of 3925—3825 BC. The Nebelivska group marks the migration of the Western Trypillia culture populations to the north-eastern direction, towards the Middle Dnieper region. Its further development between the Ros and the Dnieper rivers resulted in the formation of Kanivska local group, which pottery is also characterized by the influence of the Eastern Trypillia traditions. In the indigenous area the Nebelivska local group was replaced by the Tomashivska group.

Web technologies in cartographic support of geological exploration

Web technologies are now an integral part of the implementation of research work in various branches of science. The geological and geophysical direction is no exception, where the planning and execution of geological and geophysical surveys depend on the accuracy, reliability and relevance of the transmitted information.The article deals with the possibilities of web technologies for cartographic support of geological exploration – a complex of scientific and production works, designed to determine the industrial significance of mineral deposits (ore, hydrocarbon, etc.). Examples are given of the use of geoportal solutions for the publication of data on the territory of study.Taking into account the current level of web technologies development, a proprietary web-service was created to provide operational access to geodata during geological and geophysical work. The presented solution is implemented using PostgreSQL DBMS, PostGIS geospatial data processing module, Leaflet JavaScript library. The resulting interactive map allows to perform operational monitoring of field crews during seismic exploration, provides information on the stages of data processing and interpretation. Also it allows to implement a unified geoinformation space for joint work of specialists from different industries.

Combination of ground penetrating radar and seismic surveys of the tailings dam

Identification of water-saturated zones in the tailings dams is an actual scientific and practical task in terms of providing, first of all, their mechanical strength and filtration stability. Use of active sounding geophysical study methods allows obtaining sufficiently detailed information about the peculiarities of the internal structure of the tailings dam and the degree of water saturation of the composing soils. The paper presents the results of in-situ experiments on the study of the tailings dam of the mining enterprise by ground penetrating radar (GPR) and seismic methods. A comparative analysis of the conducted studies has allowed clarifying the internal structure and assessing the dam’s condition, paying special attention to the identification of local zones of increased water saturation and filtration. Based on the calculated correlation coefficient of electromagnetic and seismic wave velocity values, it was revealed that synchronization of geophysical surveys allows significantly increasing the reliability of in-situ determinations, as well as obtaining more reliable data. The results of the studies are the basis for predicting the most vulnerable places (zones) of a bulk ground hydraulic facility, as well as the localization of water-saturated areas in the body of the ground structures with greater reliability and performance.