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Satellite observations of the Antarctic surface since the 1990s, coupled with geophysical surveys of the flow and form of its giant ice sheet, have revealed accelerating loss of ice to the oceans. This, coupled with a reduction in floating sea ice surrounding the continent and the occurrence of unprecedented heatwaves, point to a continent being changed irreversibly by fossil-fuel burning and the global heating that results. A changing Antarctic continent will have global consequences, including sea level rise of possibly more than 1 meter in this century (and much more afterward) and by a reduced ability to naturally reflect incoming solar energy—which would lead to further heating by absorption on land and at sea as the ice pack retreats. [ABSTRACT FROM AUTHOR]

We expound on a hydrographic and geophysical survey in the south of the Archipelago of San Andres, Providencia, and Santa Catalina (ASAPSC) in the Colombian Caribbean Sea. In 2017 and 2018, high-resolution data were acquired from the Caribbean Center for Oceanographic and Hydrographic Research (CIOH). The hydrographic data were processed and filtered per International Hydrographic Organization (IHO) standards and the geomagnetic data were processed, corrected, and filtered to improve the interpretation. We could then characterise the submarine relief, analyse the geomagnetic anomalies in the area, and identify different relief forms of volcanic origin. Regarding geomagnetic work, a spectral analysis of the anomalies revealed highly magnetic bodies in deep water and residual magnetic anomalies strongly related to the seabed morphology. Magnetic highs associated with the basement highs and volcanic cones were detected. Complementary spectral analysis showed that the shallowest magnetic sources were in the first 500 m, whereas the deepest magnetic sources were between the depths of 4 and 5 km. The geomagnetic data were also validated using Euler deconvolution analysis, which confirmed these magnetic anomalies. Thus, a direct relationship between the magnetic anomalies and bathymetry of the seafloor was confirmed, reinforcing the theory of the volcanic origin of these islands. [ABSTRACT FROM AUTHOR]

This paper explores some challenges of archaeological interpretation and classification through an enclosure at Inchnadamph in Sutherland, northwestern Scotland, a site that has proven difficult to interpret. Despite a small number of archaeological interventions, including topographic and geophysical survey and excavation, the site remains enigmatic. We discuss the different interpretations suggested for the site in turn, concluding that the enclosure does not fit readily into existing classification schemes. This raises issues surrounding the use of classification systems, prior assumptions, and the need for critical thinking in interpretation. These are universal issues, applicable beyond the Scottish example chosen, and this paper highlights concerns and difficulties encountered by all who deal with the classification of sites and monuments. Ultimately, this challenges some of our preconceptions and sheds light on the limits of our knowledge, as well as the limits of our classification systems. [ABSTRACT FROM AUTHOR]

In the field of the restoration of monumental heritage, non-destructive geophysical techniques have gained an already widely acknowledged importance. The possibility to understand the state of preservation of the artefacts without resorting to a destructive action is extremely useful in identifying unknown or presumed emergencies in order to better lead the restoration operations. At present geophysics is underutilised and furthermore, common techniques may not be optimal for some specific targets or sites. Therefore, more controlled research is needed to better understand the applicability of these methodologies when searching for cultural heritage applications in various material types. The purpose of this paper is to provide a new approach that involves the joint use of several geophysical methods for the study of the probable causes of deterioration on a monument of considerable historical and artistic importance. The monument is the Basilica of Santa Croce in Lecce. It is a baroque church internationally well-known. The starting point of this research was the evidence that some structures of the façade are more damaged and present signs of subsidence. The study of the causes of damage was dealt with a geophysical survey using ground-penetrating radar and electrical resistivity tomography. The results demonstrate the effectiveness of the choice of the two methods and allow to obtain information on buried structures both inside the church and on the façade and to locate and identify anomalies related to a restoration intervention carried out in the 80s. Furthermore, a microclimatic analysis performed inside the Basilica shows a probable connection between the humidity present on the surface and the conductive layers present in the subsoil and highlighted with the electrical method. [ABSTRACT FROM AUTHOR]

To better understand the location and help in the conservation of buried structures in the ancient site of Tusculum, in Central Italy, archaeological and multi-methodological geophysical studies were developed in the recent last years. These studies included geophysical surveys, which were combined with topographical survey and direct archaeological excavations. Tusculum is one of the largest Roman archaeological sites in the Alban Hills, located in the Latium region (Italy), about 25 km South-East of Rome. This settlement was inhabited since pre-Roman times, up to the middle ages. The objective of the Tusculum Project is to verify the town-planning of Tusculum and to obtain information about the location, shape, depth and size of the hypothesised buried buildings. With these aims, multi-methodological geophysical surveys have been carried out in the time range 2016–2019 to locate the archaeological remains in different portions of the studied area and to verify the orientation of the underground aqueduct system. GPR and gradiometric surveys were carried out to investigate the archaeological remains, while ERT surveys, were employed to find evidence of undiscovered parts of the underground aqueduct system. These results, along with geological studies and historic evidence, are being examined by archaeologist to understand the limits of the town and how water was supplied to such a large, populated settlement. The obtained results show very good correspondence between the buried architecture, the geophysical anomalies and the archaeological excavations. A number of unexpected buried buildings were discovered, which were excavated in 2017 and 2018, which showed remains of buried public thermal bath and a large church with surrounding funerary area built in the Middle Ages. [ABSTRACT FROM AUTHOR]

The geological map of the Klenov Pluton (Moldanubian Batholith), and its 3D visualization, brings the new findings in the context of granite emplacement within late-Variscan settings. The Klenov Pluton has a peraluminous composition resulting from partial melting of metasedimentary sources and subsequent differentiation. The new ages 327.14 ± 0.21 Ma and 327.80 ± 0.37 Ma, reflect the narrow time-span of magma emplacement and cooling. The 327 Ma Klenov Pluton was emplaced syntectonically as a 'sheet-like' granite intrusion at depth ca. 10 kilometers during the later stages of the Pelhřimov Core Complex exhumation (at ca. 329 to 327 Ma) associated with ~N--S oriented compression. Gravity modelling suggests that the Klenov Pluton has an asymmetric shape where its western flank is parallel to the ~NW moderately dipping Pelhřimov Core Complex. The eastern margin of the Pluton is shallower and has been later modified by ~SE-side-up normal faulting (Lodhéřov Fault Zone). [ABSTRACT FROM AUTHOR]

Evidence of precontact agricultural practices demonstrating how and where crops were grown is often scant because of poor preservation and modern land use practices. As a result, relatively few sites have been identified that document farm fields or garden beds. We document remnants of a ridge and furrow agricultural system found at Angel Mounds, an important regional Mississippian site, in Indiana, USA. Researchers have identified many different cultigens from Angel Mounds, but the location, type, and age of fields had not been identified previously. Our research team recovered data indicating that the third terrace of Angel Mounds supported ridge and furrow agriculture where villagers grew maize, beans, and gourds for several centuries. This study suggests that agricultural evidence is extant in buried contexts and that these features are easily overlooked using traditional geophysical and survey techniques. [ABSTRACT FROM AUTHOR]

Airborne spectral gamma-ray survey data were processed using Th-normalization technique for oil and gas exploration in the Qaret El-Soda area, Western Desert of Egypt. This technique was applied to suppress the effects of surface lithology, which are the main factors influencing the variation of radioelement content in rocks. Normalization of K and U by thorium yielded residual potassium and residual uranium estimates. Possible occurrences of new hydrocarbon microseepages were determined by mapping low values of residual potassium and high values of residual uranium relative to potassium, which are indicated as DRAD values, which were obtained by subtracting residual potassium from residual uranium values (eUresid – Kresid). Lower residual values of K, which were associated with higher DRAD anomaly values, highlight areas of prospective hydrocarbon accumulations. The obtained results from quantitative analysis and interpretation of aeromagnetic data show sufficiently thick sediments, probably suitable for the accumulation of hydrocarbons. This means that the study area may possess a potential for hydrocarbon exploration if supported by other detailed geophysical and geochemical exploration techniques. [ABSTRACT FROM AUTHOR]

The expedition led by Francisco Vázquez de Coronado from west-central Mexico into the American Southwest from 1540 to 1542 had a profound and lasting impact on everybody involved. The exploration sought an overland route to Asia and to establish trade relations. The enterprise was also the first major contact between foreigners/others and Indigenous peoples of northern Mexico and the American Southwest. Research at Piedras Marcadas Pueblo, an ancestral village of the Southern Tiwa in central New Mexico, has material evidence and artifact patterns reflecting the cultural groups on the exploration and those with whom the expeditionaries ultimately fought. Geophysics surveys and metal detection have found evidence of a major battlesite at the pueblo. Specific artifact types, such as European metal items, slingstones hurled by their Mexican allies, and piles of rocks thrown back by Pueblo defenders all attest to the conflict and the hard-fought Tiwa resistance. [ABSTRACT FROM AUTHOR]

The results of the geophysical surveys carried out in the city of Ugento, specifically in the St. Antonio area and into the Medieval Castle, are presented in this paper. The aim of this study is to integrate the results of Ground-Penetrating Radar and Electrical Resistivity Tomography surveys in order to support archaeological investigations aimed at the elaboration of a detailed archaeological map of the Messapian, Roman and Medieval settlement. Indeed, the obtained data were jointly analysed with archaeological data already known and were georeferenced on the general plans of the site in order to obtain an overall view of the anomalies detected by geophysical instrumentation and related to buried ancient structures. In particular, the geophysical surveys carried out in the St. Antonio area made it possible to reconstruct a stretch of the Messapian city walls and nearby necropolis, while the investigations inside the Castle allowed for the acquisition of very interesting data about previous phases dated to the Middle Ages (and maybe also the Messapian or Roman ages) and about the geo-morphological characteristics of the site. [ABSTRACT FROM AUTHOR]

The results of the geophysical surveys carried out in 2019 in the Abbey of Santa Maria di Cerrate (Lecce) are presented in this paper. The objective of this study was to achieve a better knowledge of the site, since it was only partially investigated by small archaeological excavation samples. The geophysical measurements were conducted inside and outside the church in order to identify buried ancient structures, using both the georadar and geoelectrical survey methodologies. The results of GPR (ground-penetrating radar), ERT (electrical resistivity tomography) and IP (induced polarisation) were jointly analysed with archaeological data already known and were georeferenced on the general plans of the site in order to obtain an overall view of the anomalies detected by geophysical instrumentation and probably linked to buried ancient structures. [ABSTRACT FROM AUTHOR]

This paper presents an archaeological reconsideration of the chapel of St Pancras at St Augustine's Abbey, Canterbury, using published and archival sources from over a century of excavation and archaeological survey. The evidence considered, including previously unpublished elevations and geophysical survey, sheds new light on the chapel's structure and its context, of which it presents the fullest account yet published. Using all available sources, it is argued that the earliest phase of the ruinous building neither dates from the Roman period, nor from the mid- to late 7th century, as previously argued by other scholars, but from between 597 and 609. The same evidence supports the interpretation that the structure was rebuilt in the 7th and 8th centuries. As such, the first phase of St Pancras may be both the oldest 'Anglo-Saxon' ecclesiastical building visible today, and founded, consecrated and used by Saint Augustine of Canterbury himself. It provides, therefore, unique testimony to a pivotal moment in British history and offers previously unrecognized material evidence for the foundation of the English Church. [ABSTRACT FROM AUTHOR]

This paper reports the results of the integrated geophysical surveys performed inside the Monastery of St Chiara in Nardó in southern Italy. Ground-penetrating radar (GPR) and electrical resistivity tomography (ERT) investigations were carried out to find the tomb of Sister Chiara D'Amato, whose location has been lost over the centuries. Sister Chiara Isabella D'Amato was a charismatic and holy figure. She died in 1693. She was buried inside the monastery but her body has never been found. The data acquisition was performed along with a series of closely spaced lines for GPR and using a non-standard array for ERT. Data were processed and visualised as two-dimensional vertical sections and depth slices or three-dimensional volumes (GPR and ERT) to allow an integrated interpretation of the geophysical results. The analysis of the geophysical data sets revealed a series of anomalies that could be ascribed possible archaeological structures, probably related to the earliest ages of the sacred building as well as other anomalies (bedrock, fractures) of presumable natural origin. In particular, one geophysical anomaly was suspected of being connected to burial and consequently further investigated with the use of a video endoscope. The results reveal the presence of a void but it has not yet been clarified whether it is the burial of Sister Chiara or not as it is awaiting the excavation. [ABSTRACT FROM AUTHOR]

The site of Sembiran on the northern coast of Bali was an important trading harbor with demonstrated intensive links to the Indian subcontinent, the Western Indian Ocean, and Mainland Southeast Asia between the second century BC and the second century AD. Using a combination of excavation and geophysical survey, we have newly mapped a dense network of subsurface structures, which we interpret to be foundations for harbor infrastructure dated to the eighth to ninth centuries AD that were subsequently covered by shoreline aggradation. An assemblage of eighth to twelfth centuries AD Chinese tradeware in dated contexts from our excavations of these shoreline structures and additional trenches further inland suggests a renewal in trade activities at Sembiran, coinciding with the growth of Chinese maritime trade in Island Southeast Asia. [ABSTRACT FROM AUTHOR]

The application of appropriate geophysical survey is very pertinent in planning for a successful development of civil engineering structures. In this study, an uphole seismic refraction survey and borehole logs were used to determine the foundation bed’s characteristics for civil engineering development, while a portable gamma spectrometer was used to assess the environmental safety worthiness in some parts of Bayelsa State, Nigeria. The seismic refraction revealed a two-layer model, composing of an unconsolidated layer and a consolidated layer. The overburden thickness of the unconsolidated stratum varied from 2.2 to 7.5 m. The borehole logs showed alternating sequence of clay and sand up to a depth of 60 m. The radiometric survey revealed that thorium and the average radioactivity ratios of U/K, Th/K and U/Th are above the global standards by factors of 1.4, 6.4, 11.0 and 2.3 in sequence. Though the overburden in the study area is thin, it is advisable to excavate some aerated soil materials within the unconsolidated layer to minimize the effects of clay on the structure’s foundation. Furthermore, periodic environmental safety monitoring and assessment is recommended in the study area. [ABSTRACT FROM AUTHOR]

The selection of the most appropriate method(s) for a specific engineering geophysical site characterisation can be challenging due to the complexity and potential ambiguity of the factors influencing the utility and cost-effectiveness of the methods. This paper, using matter-element analysis techniques with analytic hierarchy process (AHP), proposes a demonstration matter-element model for selecting the most appropriate geophysical methods, and establishes the general flow and calculation process for geophysical method selection. On the basis of the analysis of the factors influencing the utility and cost-effectiveness of geophysical methods, an evaluation criteria system is constructed. To demonstrate the application of this process, the proposed matter-element geophysical methods selection mode is applied to the selection of geophysical methods for an engineering geophysical site characterisation project that ultimately involved the acquisition of electrical resistivity tomography (ERT), multichannel analysis of surface wave data (MASW) and ground penetrating radar (GPR). The optimal results, based on the matter-element model, indicate the recommended geophysical methods are consistent with the field methods ultimately employed. The research proposes a new quantitative and objective computing approach to the selection of geophysical methods. The matter-element model can minimise subjective influences to a certain extent, and is conducive to enhancing the utility and cost-effectiveness of a geophysical survey. [ABSTRACT FROM AUTHOR]

On October 2016, during a geophysical survey in the Naples harbour aimed at evaluating its geo-archaeological potential, a wooden-hulled shipwreck was found along with a large amount of wreckage material. Cartographic evidence and preliminary underwater survey of the shipwreck have led its identification as the corvette Flora, which was deliberately burned 8 January 1799, along with five other ships and about 100 minor vessels of the Bourbon fleet before the French army arrived in Naples. This represents the first find and in situ underwater observation of an 18th-century sailing vessel in the bay of Naples. Our research contributes to knowledge of the events that led to the destruction of the fleet in 1799 and provides new, still preliminary, insights into the construction details of Bourbon vessels. [ABSTRACT FROM AUTHOR]

Multi-disciplinary exploration methods are used to explore for possible ore deposits in the Sonqor area, Iran, which lies within the Sanandaj-Sirjan Zone, and contains significant iron, copper and gold mineralisation. Hydrothermal alteration was mapped using field, remotely sensed, geophysical and geochemical data as well as Landsat-8 Operational Land Imager, Landsat Enhanced Thematic Mapper plus, and two Advanced Space Borne Thermal Emission and Reflection Radiometer images. Image processing techniques, viz band ratio, principal component analysis (PCA), and various spectral analysis methods were applied to map the distribution of hydrothermally altered rocks (geochemical halos) associated with porphyry (e.g. Cu–Au) mineralisation. The geochemical halos enabled vectoring to mineralised zones with mapping of advance argillic, argillic, carbonates, Fe-oxides, phyllic, propylitic and silicification using minerals such as alunite (K/Na), muscovite, kaolinite, illite, chlorite, goethite, hematite, jarosite, calcite and silica/quartz. The band ratio combination of sensors for mapping altered areas show promising results, similar to other more advanced methods. PCA exposed variations in the spatial distribution of more hydroxyl-based minerals like alunite/jarosite, whereas the geophysical magnetic survey identified the main lineaments, possible faults and magmatic intrusion boundaries. While geochemical methods show the potential occurrence of elements like Fe, Au and Fe-bearing Ti in the southeast and southern parts, and skarn-type anomalies in the northern part of Sonqor, leaking of specific geochemical elements (such as Fe, Au and Fe-bearing Ti) produce false anomalies. Copper, Pb and Zn anomalies in the central part show the possibility of sulfide-based mineralisation. Space-based satellite technologies were used to identify mineral prospects in the Sonqor area, within the iron, copper and gold-rich Sanandaj-Sirjan Zone, Iran. The Sonqor area, part of the Zagros Orogen, is within the extensive Alpine–Himalayan orogenic belt formed by collision of the Arabian continent with the Iranian microcontinent in the Late Cretaceous to Cenozoic. The western part of the Sonqor area has first rank Hg, Au, Ag, Ta and Sb anomalies with abundant detachment faults. Dacite domes with surrounding alteration have potential for Au epithermal mineralisation (Dashkasan type); the central part may yield Cu, Zn and Pb sulfide mineralisation. The Sonqor geological map suggests good potential for Au, Fe and Fe–Ti mineralisation at the contact between limestones in the eastern and southeastern parts, but greenschist and amphibolite facies metamorphism necessitates caution in interpretation of geochemical anomalies. [ABSTRACT FROM AUTHOR]

The identification and characterisation of faults in urban environments is important to inform seismic and landslide hazard, yet urban development often obscures geological and geomorphological evidence of fault traces. On the other hand, urban development also generates a wealth of borehole data, which, when combined with geophysical surveys, can enable a view into the subsurface. Here we combine geomorphological and geological mapping, gravity surveying, and 3D geological modelling to identify, map and characterise several faults in Beachlands, Auckland, some of which have large offsets. Our work has identified one new fault, the Motukaraka Fault, and confirmed the presence of two proposed faults, the Waikopua North and Te Puru faults. The Motukaraka and Waikopua North faults are both steeply dipping normal faults, which strike NNW and downthrow Mesozoic basement to the west. The Motukaraka Fault has an offset of 250 m (±100 m) and the Waikopua North Fault a combined offset of 240 m (±50 m) across two parallel fault segments. The Te Puru fault strikes northeast near the northern extent of the Waikopua Fault, and downthrows Mesozoic basement to the northwest by 60–100 m. Further investigations are required to determine whether these buried faults are active. [ABSTRACT FROM AUTHOR]

The research area falls at the downstream level of Bhalujhora landslide area in Alay which is located in Pasakha, Bhutan. Local Government authority proposed for construction of custom station between the commercial town Phuentsholing and Pasakha Industrial estate. However, downstream region which connects the core town to industrial estate are severely affected by the flash floods every year and the runoff causes huge sediment deposits leading risk for community and substantial damages to the infrastructures. The site is seasonally eroded and subsequently deposited by the sediments from upstream. Although, the formation level for infrastructure are proposed on the deposit layer, the assessment of soil parameters is necessary for design and planning to ensure the overall safety and long-term economic benefits. Through this study, the subsurface soil parameters are assessed by in-situ open pit investigation, geophysical survey and Standard Penetration Test (SPT), while the engineering properties of the sediment deposits were determined from laboratory tests. The field investigation was important to decide the suitability of foundation type and depth. Further, soil parameters were determined to classify the soil type, understand permeability characteristics, and predict shear strength parameters and compaction behaviour. The result shows that the sediments consist of mixture of natural aggregates and sand mixed with silt and clay. An estimate of sediment accumulation was carried out to determine the volume of the sediment deposited. The outcome will allow the relevant stakeholders to decide the management of the risk from this future disaster and propose alternative use of the sediment materials in road works. [ABSTRACT FROM AUTHOR]

Shell middens, or shell-matrix deposits, occur in large numbers across the coastlines of the world from the mid-Holocene (ca. 6000–5000 cal BC) onwards, often forming substantial mounds. However, they become smaller, rarer or absent as one goes back into earlier periods, suggesting a world-wide process of economic intensification. Since sea level was generally much lower during these earlier periods, a critical question is the extent to which mounded shell middens could have accumulated on now-submerged palaeoshorelines, and if so, how they were affected by the potentially destructive impact of sea-level rise. Further, and important to modern practice, it is essential that archaeologists consider how such sites can be discovered through underwater investigation. Here we offer a proof of concept that shell middens can survive submergence and can be detected, using systematic investigation of a rare example of a confirmed underwater shell midden at the Mesolithic site of Hjarnø (ca. 5300–4300 cal BC) in Denmark. We compare the excavation results with the results of geophysical survey, explore the problems of distinguishing underwater cultural shell middens from natural shell beds and conclude that shell middens can survive inundation by sea-level rise and can be detected by remote sensing, but require at least minimally invasive sampling to establish their cultural status. We suggest the methods developed may be applicable to coastal and marine sites impacted by postglacial sea-level rise worldwide. [ABSTRACT FROM AUTHOR]

The Caribbean island of Carriacou is notable for its recurrent drought, paucity of large, native land animals, and well-developed bank and barrier reef system. These environmental conditions presented challenges and opportunities to the Amerindians, Europeans, and enslaved Africans who settled here through time. While available evidence suggests human presence has altered island ecology through agriculture, deforestation, erosion, species introductions, and extinction, overall human ecodynamics remain poorly understood. In 2018, the Carriacou Ecodynamics Archaeology Project (CEAP) initiated a field program investigating long-term human-environment interaction to reconstruct Carriacou's landscape history. The CEAP seeks to develop high-resolution records for anthropogenic habitat modification and change in biotic communities from initial Amerindian settlement (ca. AD 400) through the colonial period (1740s–1974) up to the present. Pilot investigations comprising pedestrian survey, test pitting, site mapping, and geophysical survey targeted the coastal archaeological site Sabazan, where ca. 1,600 years of pre- and post-contact settlement are recorded. Here, we present the results of this first field season, demonstrating the potential of geophysical survey approaches in the Caribbean and the need for renewed, focused attention to Carriacou's archaeological resources which are being rapidly lost due to coastal erosion. [ABSTRACT FROM AUTHOR]

We present a new seafloor sedimentological map of Bagnoli-Coroglio SIN (Sites of National Interest) in the Gulf of Pozzuoli (Napoli), Italy, based on the analysis of the acoustic backscatter, calibrated with grain size distribution of sampled surficial marine deposits. Geophysical and ground-truthing (geological) data were acquired during a series of marine surveys designed for a seafloor characterisation aimed at remediation of the marine environment offshore the dismissed industrial area of Bagnoli. This study describes the acquisition and processing of the multibeam echo-sounder (Reson SeaBat 7125 high-resolution) backscatter data recorded during geophysical survey and illustrates the approach followed in the construction of a high-resolution seafloor map of the Bagnoli-Coroglio offshore. [ABSTRACT FROM AUTHOR]

A newly discovered network of later Bronze Age fortified sites of unusually large size are discussed, with a primary focus on results of excavations at the site of Gradište Iđoš. Closely associated with the rivers Mureš, Tisza, and Danube, these sites are located in the southeast of the Carpathian Basin in central Europe. On current evidence, the main period of construction and occupation took place between 1400–1100 b.c., probably constituting successor communities of the tell-centred societies of the Middle Bronze Age. Geophysical survey and excavation results from Gradište Iđoš, the largest site in this network in Serbia, are presented in this paper within their regional context. We discuss preliminary insights into the structural development of the site, alongside a correlation of new 14C dates with relative ceramic chronological markers and the results of faunal analysis. These results provide new perspectives on settlement systems at the dawn of Urnfield cultural traditions in this region. [ABSTRACT FROM AUTHOR]

A combination of geospatial, geophysical and statistical models using satellite data, the weighted index overlay (WIO) method and two-dimensional electrical resistivity tomography (2D-ERT) is applied to generate the highest potential groundwater area and to further explore the groundwater in Dehradun, India. The results show that of 19.7 km2 total basin area, 0.26% falls under the "poor" category as a prospect zone for groundwater, 4.3% is "moderate", 10.10% "moderately good", 4.9% "good" and 0.17% "very good". In addition, the demonstration of the geophysical survey is presented, in which Purkal Youth Society Division (PYSD) site is categorized as a shallow aquifer zone and the Guru Nanak Fifth Centenary School (GNFCS) site is a deeper aquifer zone. Our study emphasizes remote sensing and geographic information system integrated with a geophysical survey to support prospecting the most probable area and confirm the existence of groundwater. [ABSTRACT FROM AUTHOR]

In this study, we have analyzed the comparative potential of reflectance and emittance bands of advanced spaceborne thermal emission and reflection radiometer (ASTER) sensor for detecting surface exposures of Proterozoic rocks and gossan capping of gold mineralization. In this regard, few new image analysis products are derived. These are matched filtering factor-modified ratio (MFR) image and the inverse of a difference image of the ratio and matched filtering map (IDRM). These image products are used with the conventional ratio images, relative band depth images and index-based principal component (PC) images of reflectance and emittance bands of ASTER for delineating metasediments of the study area. We have found that reflectance band products are superior for mapping metasediments and gossan capping than the emissivity products, which are only suitable to enhance quartzite. Self-potential (SP) geophysical survey is carried out around the identified gossan site as SP is sensitive to sulphide mineralization. Results of the SP survey indicated presence of sulphide enrichment underneath the gossan. [ABSTRACT FROM AUTHOR]

In 1940, with the fall of France imminent, Britain prepared secret 'Auxiliary Units' tasked with guerrilla activities [Scallywagging] in the invading army's rear. Patrols of four to eight highly skilled men used below-ground Operational Bases (OBs) in remote locations to avoid detection. No official records are released, but OBs were 'Mark I', enlarged deer setts, smuggler caves, etc., and Mark II, prefabricated designs by the Royal Engineers. This paper details three sites in Suffolk: one unknown Mark I was destroyed, a Mark II was partially intact and a Mark II was fully intact, all in secluded woods. Geophysical surveys found metal detectors optimal for location, with mid-frequency GPR/ERT optimal for characterisation. Archaeological finds included home-made braziers, 1940 kerosene heater stove, metal pans, ventilation systems and escape tunnels. This study shows OBs varied in construction and condition, with surveys detecting and characterising them, bringing WWII British 'invasion' history into the wider scientific community and public domain. [ABSTRACT FROM AUTHOR]

A project to investigate stories of escape attempts at the Second World War Prisoner of War camp at Cultybraggan in Perthshire undertook geophysical survey and excavation to try to locate escape tunnels. While the limited fieldwork did not locate any traces of the tunnels themselves, the work provided insights into the psychology and practice of escape attempts amongst the German PoWs. [ABSTRACT FROM AUTHOR]

More than 80 Cenozoic low sulphidation Au–Ag epithermal deposits and prospects are known in Northland, the Hauraki Goldfield (Coromandel Volcanic Zone) and the Taupō Volcanic Zone of the North Island. Reconnaissance exploration since the 1970s has included magnetic surveys, and stream sediment and rock-chip geochemical surveys. Prospect-scale exploration over the same period has included rock and soil geochemical surveys, magnetic and resistivity/induced polarisation geophysical surveys and drilling, including the study of hydrothermal alteration mineralogy (by thin section and XRD) plus fluid inclusion systematics, to help reconstruct the former hydrothermal system and identify zoning related to mineralisation. Since the 1990s, digital regional exploration and research data sets have enabled GIS-based targeting of prospective areas. At the prospect scale, multi-element ICP and ICP-MS analyses, hyperspectral short wave infrared spectral analyses and portable XRF geochemical analyses of field samples and drill core have been used to complement assay data for identifying spatial trends in geochemistry and mineralogy that help vector to mineral occurrences. Exploration since the 1970s has discovered new Au and Ag resources in extensions of some previously mined deposits (e.g. Golden Cross and Karangahake) and in new deposits in adjacent areas (e.g. Favona, Trio and Correnso in the Waihi area). [ABSTRACT FROM AUTHOR]

Geophysical survey of the transepts and crossing needs to be confirmed by excavation, as does the "holy well" lying almost centrally in the crossing but not aligned on the abbey church; this clearly predates the early 13th-century church, but by how long? The initial founder, the English Robert fitz Stephen, gave way to Rhys ap Gruffydd, Prince of Deheubarth, and it was under the Lord Rhys that the abbey moved to its permanent site in 1201. Stephen Williams, the first excavator of the abbey site in 1887-90, identified Henfynachlog as its original setting - which recent research has not confirmed, though the Cistercians, and particularly the family of Clairvaux, regularly used timber buildings until they had reached I stabilitas i . [Extracted from the article]

Historic Fort Wayne is located on the Detroit River in a landscape of heavy industry and marginalized urban neighborhoods (figure 1). Geophysical survey south of the Fort Wayne Mound—a Late Woodland Period burial mound enclosed by the Fort—indicates that pre-contact residential structures may be preserved at the site. Residential sites with mortuary monuments are uncommon in southeastern Michigan and represent an opportunity to better understand variation in Late Woodland settlement. Our approach combines existing archaeological research, historical records, and non-invasive geophysical survey in a culturally sensitive Native American site context presently unavailable for conventional archaeological excavation. We examine archaeological and historical records from Springwells and Late Woodland period settlements in the region to contextualize geophysical evidence from the site. The research prioritizes protection of Native American heritage sites in urban contexts together with ongoing archaeological interpretation of the Late Woodland cultural Landscape. [ABSTRACT FROM AUTHOR]

Documentary evidence describes how in 1549, during the suppression of the chantries under Edward VI, the medieval chapel in Malham township was destroyed. Combining this evidence with aerial photographs and geophysical surveys, a potential site for the ancient chapel and cemetery was identified. Between 2015-2017 archaeological excavations confirmed that this site was the ancient chapel. The notes update the original article about Malham chapel in Northern History, 52 (2015), which was written before the excavations began. [ABSTRACT FROM AUTHOR]

Documentary evidence describes how in 1549, during the suppression of the chantries under Edward VI, the medieval chapel in Malham township was destroyed. Combining this evidence with aerial photographs and geophysical surveys, a potential site for the ancient chapel and cemetery was identified. Between 2015-2017 archaeological excavations confirmed that this site was the ancient chapel. The notes update the original article about Malham chapel in Northern History, 52 (2015), which was written before the excavations began. [ABSTRACT FROM AUTHOR]

In many geological scenarios, the interpretation of multiple geophysical datasets through the use of joint inversion has become a common practice provided all data share compatible spatial resolution. Unfortunately, this requirement has also limited the application of airborne electromagnetic (AEM) data in joint inversion. For instance, we commonly assume that airborne gravity and magnetic datasets largely originate at a depth of a few kilometres, whereas co-located AEM signals can only penetrate a few hundred metres, thus rendering spatially incompatible datasets. We believe, however, that a fraction of these datasets originate from the same structures and provide a common ground for structural joint inversion strategies. We aim to explore the viability of jointly inverting such datasets using potential and AEM field data acquired in Western Australia with three comparative experiments. First, we generate conventional 2D separated models for each dataset to gauge their individual resolution capability. We then perform the 2D cross-gradient joint inversion of gravity and magnetic datasets. Finally, we adapt the structural joint inversion to include the AEM resistivity model as a constraint. We show that there is an area commonly sensed by the three datasets and that the coupled resolution influences both shallow and deep structures of the joint models. This yields a coherent integrated interpretation of shallow and deep structures of the studied section, which is validated when compared to a nearby seismic traverse section. Airborne collection of electromagnetic and potential field data is a common strategy for extensive resource exploration and reconnaissance. Since these datasets contain information about different properties at different depths, they are normally considered complementary and are interpreted separately. Using airborne data acquired in Western Australia, we explore the viability of their joint inversion and show the advantages of their combined analysis and interpretation. [ABSTRACT FROM AUTHOR]

Geophysical surveys are commonly used in areas where the presence of ancient civilizations is historically documented. These investigations are able to detect through indirect methods the presence of bodies or structures in the subsoil measuring the variations of some physical parameters, obtaining information about archaeological remains without causing harm to them. In the present study, we investigated the presence of anthropogenic buried cavities partially filled with rubble material, in an area located in the northern part of Cava Ispica, one of the most important archaeological sites located in south-eastern Sicily. The results of seismic refraction prospections, processed with tomographic methods, are presented and discussed. The entire valley contains prehistoric burial sites, Christian catacombs and residential units of various kinds. Despite the numerous searches made over past years, much still remains to be discovered. The seismic refraction tomographic data, analyzed in 3D, revealed the presence of low velocity values (<400 m/s) areas that, considering the lithotypes locally present and the features of other archaeological structures discovered during previous surveys, can be ascribed to the presence of possible cavities. The obtained results show how such geophysical inspections represent an important preliminary tool for archaeological surveys. [ABSTRACT FROM AUTHOR]

Large scale geophysical survey has identified two classic henges in the Wharfe Valley and excavation at the henge at Yarnbury has proved its Bronze Age date, reuniting it with antiquarian finds hitherto lacking secure provenance. These henges are placed in their archaeological context suggesting that Wharfedale may have been an important route in cross-Pennine contacts during the third and second millennia BC and that the Neolithic archaeology of this upland region may be more mainstream than peripheral. [ABSTRACT FROM PUBLISHER]

A new survey of Scolland’s Hall in Richmond Castle identifies it as an early example of an integrated hall, chamber and garderobe. The hall was entered at one corner and the entrance to the chamber was at the opposite corner, suggesting that it had a low end and high end of the conventional form better known from buildings of the thirteenth century and later. The chamber was relatively small and had a mural fireplace set in the middle of the longer wall. It had a door to a projecting balcony, while a further balcony was provided overlooking the River Swale alongside the undercroft. The building is dated to the 1080s. It is argued that the features which appear to be unusual at Scolland’s Hall – the location of the hall at first-floor level, the organization into a low and high end, the integration of the hall and chamber, and the use of viewing balconies – have parallels in other near-contemporary buildings. [ABSTRACT FROM PUBLISHER]

The systematic exploration of large archaeological sites in the Mediterranean has evolved considerably since the “big dig” excavations. Pedestrian field surveying and remote sensing applications, including satellite and airborne image analysis, are now practical and relatively cost-efficient methods of characterizing large and diachronically diverse landscapes on regional scales. However, the use of geophysical techniques as a means for exploring manifold archaeological contexts is still in its infancy. In this paper, we highlight the advantages of archaeological geophysics to conduct regional surveys in the Mediterranean. Through a multi-site geophysical fieldwork campaign to investigate the patterns and dynamics of ancient cities in Greece, we show how geophysics offer new opportunities for characterizing the spatial attributes and regional dynamics of urban landscapes, and, in doing so, we make an argument for its wider adoption on regional survey projects. [ABSTRACT FROM PUBLISHER]

The results of an integrated geophysical survey at the archaeological site of Abu Serga church, Cairo, Egypt are presented and discussed. The aim was to investigate the ground conditions of the Church of Abu Serga (St. Sergius), the Cairo’s oldest, dated from 4th Century church, which is located at Qasr el-Shama in old Cairo in Egypt. In particular the objective is to study the subsurface geological structures at the location of the church, and to detect and possibly map any ancient remains concealed under the monument. The survey was conducted using two geophysical methods: the ground penetrating radar (GPR), which is a fully non-destructive method, and the electrical resistivity tomographies (ERTs). The usefulness of combining conventional geophysical mapping techniques and high resolution imaging methods in delineating shallow targets of archaeological interest at such complex archaeological sites, is studied. Ground penetrating radar time slices and 3D electrical tomography depth slices were used for the verification of specific anthropogenic anomalies, which were detected on the geophysical maps Processing of geophysical maps included filtering with the gradient and first derivative operators in the space domain and the upward continuation and Butterworth filters in the wave number domain. The integration of the geophysical measurements revealed that the present Crypt is not the original holy Crypt. The anomalous reflector is detected at depth of about 5 m below the sanctuary floor, in the form of buried ceiling of the original Crypt. The present Crypt is just a small low subterranean church belong to the 2nd century. High resistivity anomalies and distinct GPR signals were also observed deeper in the inner parts of the church. They are attributed to possible remains of ancient walls and surrounding tunnels, or other man-made structures concealed under the floor of the monument. The geophysical survey at Abu Serga church also demonstrates that the general features of the foundation soil are heterogeneous with abundance of fractures; the water table is very high at 1.8m below the sanctuary floors. The benefits of combined geophysical surveys in case of archaeological investigations at complex sites are highlighted. [ABSTRACT FROM AUTHOR]

Property damage results from liquefaction that occurs easily in soft sandy layers. Moreover, liquefaction damage tends to be more serious at locations where earthquake ground motions are locally amplified. It is commonly understood that ground stiffness is correlated with S-wave velocity (Vs); in addition, the structure of the local subsurface is important for predicting local earthquake ground motion. Surface wave and S-wave reflection surveys are efficient, non-destructive techniques used to obtain two-dimensional S-wave velocity distributions and to map subsurface structures. In this study, we performed surface wave and S-wave reflection surveys to investigate the Hinode area of Itako, Ibaraki, Japan. This area suffered serious liquefaction damage during the Great Eastern Japan Earthquake of 2011. Using subsurface boundaries imaged by the reflection surveys and the Vs structures obtained by surface wave analyses, it is possible to extrapolate geological and hydraulic information obtained by boring and cone penetration tests (CPTs). The combined information was used to delineate the layer in which liquefaction occurred, identified as an artificial layer of sandy dredged material, formed after 1970. The results of this study confirmed the effectiveness and applicability of geophysical surveys to the evaluation of the liquefaction potential. These methods enable us to predict the spatial distribution of liquefiable soils for future large earthquakes. [ABSTRACT FROM AUTHOR]

The spatial distribution of the strength inside the earth-fill is identified by the sounding tests. In this research, the Swedish weight sounding (SWS) is employed, and the spatial high-density test is performed to identify the spatial correlation structure. Furthermore, the synthesised approach of the SWS and surface wave method, which is one of the geophysical method, is proposed to compensate the shortage of each approach. Consequently, the correlation structure of an earth-fill could be identified accurately, and the high resolution of the spatial distribution could be visualised based on the survey results. [ABSTRACT FROM PUBLISHER]

Artesian springs, which form carbonate mounds at the surface, occur in groups along the southwestern edge of the Great Artesian Basin (GAB), in northern South Australia. Their underground structure and relationship to faulting are not well understood. This study investigated four mound spring groups (Beresford Spring, Warburton Spring, the Bubbler Spring group, and Freeling Springs), which have different geological settings, using a range of geophysical techniques: self-potential (SP), magnetotellurics (MT) and time-domain electromagnetics (TEM). The results confirmed that despite generally similar mound morphologies at the surface, spring vents in different groups have different mechanisms for sourcing water from the GAB aquifer. SP measurements effectively showed where most of the vertical flow occurs at all groups, while MT and TEM models identified the location of faults, other geological structures and the thickness of the Bulldog Shale aquitard. Beresford and Warburton springs are similar in that the spring locations at both are directly related to points on a regional-scale fault, which appears to provide a low permeability pathway to the surface. At the Bubbler Springs group, a regionally aligned fault identified in MT data seems to be bounding an area where the aquifer is much closer to the surface (and the overlying aquitard has been thinned) where the spring abundance is highest. SP responses indicate that shallow flow paths feeding individual vents are unrelated to the fault. At Freeling Springs, the SP suggests that groundwater is flowing up within shallow aquifers, and that spring location is offset from this upward flow, instead located on range-front faults that provide the final conduit to the surface. [ABSTRACT FROM PUBLISHER]

The Lake Tanganyika South petroleum exploration block covers the southern portion of the Tanzanian side of Lake Tanganyika and is located within the East African Rift System. The rifting process has formed rotated fault blocks which provide numerous play types in the resulting basins. Interpretation of 2D seismic data from 1984 indicated that sufficient sediment thickness is present for hydrocarbon generation. The prospectivity of the lake sediment sequence is enhanced by large oil discoveries further north along the rift system at Lake Albert in Uganda. Airborne gravity gradiometry (AGG) has been used in the Lake Albert region to delineate the structural framework of sedimentary basins. Based on this analogy, in 2010 Beach Energy commissioned CGG to fly a FALCON AGG and high-resolution airborne magnetic survey over the Lake Tanganyika South block to provide data for mapping the basin architecture and estimating the depth to magnetic basement. A total of nearly 28000 line kilometres of data were acquired. The subsequent interpretation incorporated the AGG and magnetic data with available 2D seismic data, elevation model data, bathymetry, Landsat and regional geology information. The integrated data interpretation revealed that the Lake Tanganyika rifting structures occur as half-grabens that were formed through reactivation of Precambrian fault structures. Two major depocentres were identified in the magnetic depth-to-basement map in the north and in the west-central part of the survey area with sediment thicknesses in excess of 4 km and 3 km, respectively. Smaller, shallower depocentres (with less than 3 km of sediment) occur in the southwestern region. This information was used to plan a 2100 km 2D marine seismic survey that was recorded in 2012. An interpretation of the results from the seismic survey confirmed a rifting structure similar to that encountered further north at Lake Albert in Uganda. Several targets were identified from the seismic sections for follow-up. [ABSTRACT FROM AUTHOR]

The Eureka volcanogenic massive sulphide (VMS) lens forms part of the Stockman Project in north-east Victoria. Eureka was discovered in early 2013, heralding the first new VMS mineralised zone to be discovered at the project since 1979. Key drivers to the detection of Eureka included the combination of downhole electromagnetics (EM) and a robust geological model. The lens is located 350m to the north-east of the Currawong deposit, at a vertical depth of 360 m. Surface EM methods played a significant role in the discovery of the nearby Currawong and Wilga deposits during the late 1970s. Despite this, modern day airborne and fixed-loop transient EM (FLTEM) surveys failed to detect Eureka, most likely due to its depth, moderate conductance and loop-edge effects masking anomalies. The key component in discovering the lens was the interpretation of two subtle downhole transient electromagnetics (DHTEM) responses from 2012 exploration drillholes. These responses were further strengthened by structural and short wave infrared modelling, presenting a compelling multi-component drill target. The lens was discovered soon thereafter, with a discovery intercept of 22.65m at 1.2% Cu, 0.7% Pb, 3.9% Zn, 43 g/t Ag and 1.3 g/t Au. [ABSTRACT FROM AUTHOR]

Wepresent a case study of prestack depth imaging for data from the South China Sea using an enhancedworkflow with cutting edge technologies. In the survey area, the presence of complex geologies such as carbonate pinnacles and gas pockets creates challenges for processing and imaging: the complex geometry of carbonates exhibits 3D effect for wave propagation; deriving velocity inside carbonates and gas pockets is difficult and laborious; and localised strong attenuation effect from gas pockets may lead to absorption and dispersion problems. In the course of developing the enhanced work flow to tackle these issues, the following processing steps have the most significant impact on improving the imaging quality: (1) 3D ghost wavefield attenuation, in particular to remove the ghost energy associated with complex structures; (2) 3D surface-related multiple elimination (SRME) to remove multiples, in particular multiples related to complex carbonate structures; (3) full waveform inversion (FWI) and tomography-based velocity model building, to derive a geologically plausible velocity model for imaging; (4) Q-tomography to estimate the Q model which describes the intrinsic attenuation of the subsurface media; (5) de-absorption prestack depth migration (Q-PSDM) to compensate the earth absorption and dispersion effect during imaging especially for the area below gas pockets. The case study with the data from the South China Sea shows that the enhanced work flowconsisting of cutting edge technologies is effective when the complex geologies are present. [ABSTRACT FROM AUTHOR]

The Taranaki Basin is the only hydrocarbon producing basin in New Zealand. The North Taranaki Basin has widespread two-dimensional (2D) seismic coverage and numerous wells that have not encountered commercial accumulations. This is attributed to the structural complexity in the central graben and the absence of necessary information to help understand the basin's evolution. An active petroleum system has been confirmed by hydrocarbon shows and non-commercial oil and gas discoveries (Karewa-1 and Kora-1). A broadband long offset three-dimensional (3D) seismic survey was acquired and processed by Schlumberger in 2013 to evaluate the hydrocarbon potential of the North Taranaki Basin. Innovative acquisition techniques were combined with advanced processing and imaging methods. Raypath distortions and depth uncertainty were significantly reduced by processing through tilted transverse isotropy (TTI) anisotropic Kirchhoff prestack depth migration with a geologically constrained velocity model. The survey provided the necessary information to understand the petroleum system and provide evidence for material hydrocarbon accumulations. In this investigation, we assessed the hydrocarbon potential of the North Taranaki Basin using the newly acquired data. 3D seismic interpretation and amplitude-versus-offset (AVO) analysis support the renewed potential of the basin and demonstrate effectiveness of these technologies that together can achieve encouraging results for hydrocarbon exploration. [ABSTRACT FROM AUTHOR]

The Far South project is located 5 km south along strike from the Deep South mine, where gold mineralisation is commonly associated with semi-massive pyrrhotite and pyrite. Data from a sub-audio magnetic (SAM) survey, set up in galvanic configuration, were acquired over the project principally to map stratigraphy and structure using the on-time magnetometric conductivity (MMC) and total magnetic intensity (TMI) responses. The off-time galvanic source electromagnetic (GSEM) data were subsequently extracted from the raw data and four late-time anomalous responses were identified. Two of these responses are strong late-time anomalies up to 350m in strike length, clearly visible in the 60 ms time gate, and the remaining two are weaker mid-time, subtler and less diagnostic responses. Modelling of the GSEM responses was attempted using conventional electromagnetic (EM) modelling techniques, where certain assumptions had to be made for the survey geometry and current path. The assumed current path has an effect on the coupling of the inducing current with the target, so in order to validate the assumptions and GSEM modelling results, follow-up movingloop and fixed-loop electromagnetic (MLEM and FLEM) surveys were required. These surveys confirmed well-defined conductive responses over all four follow-up areas. Modelling of the GSEM data over the two strongest anomalies is in good agreement with modelling of the MLEM/FLEM data. Modelling at a third target showed some similarity to results obtained by modelling the follow-up EM survey data, and one target was not defined clearly enough in the GSEM data to allow modelling and had to be modelled solely on the follow-up FLEM data. The results of these efforts confirm the ability to identify and produce a reasonably useful model of strong conductive targets from SAM GSEM data, indicating that the rapid acquisition SAM system is an effective tool for quick reconnaissance in sulphide exploration. Subsequent drilling identified sulphide mineralisation at all four conductors. [ABSTRACT FROM AUTHOR]

Compared to other world regions, the employment of archaeological geophysics in Sub-Saharan Africa has been particularly modest. By reviewing the few published case studies from the last fifty years, this paper emphasises the contributions of geophysical surveying to field research so far, while also addressing major changes in its practice through time. It is argued that geophysical methods are essential tools for enhancing archaeological visibility in the continent, opening up new perspectives for understanding and interpreting sites. It is expected that geophysics will play an ever-growing role in the investigation of ancient settlements and landscapes in the region, with large-scale surveys and integrative archaeological research programmes becoming commonplace practices. [ABSTRACT FROM PUBLISHER]

In many Precambrian provinces, the understanding about the tectonic history is restrained by the limited exposure of rocks so that aerogeophysical data can provide information below the surface cover of sediments, soil, and water to build a tectonic model of the region. However, the tectonic evolution of cratons and shear zones is very complex due to scarce aerogeophysical and geological data. The integrated observation of geology, aerogammaspectrometry, and aeromagnetometry of the Brazilian Shield, states of Santa Catarina, Paraná, and southern São Paulo, is enhanced by a 2011 high-resolution aerogeophysical survey. The Ponta Grossa and Florianópolis dike swarms show two sets of linear high magnetic signal. Peralkaline–carbonatitic complexes are observed in all images, e.g. Jacupiranga, Tunas, and Anitápolis. Three main geotectonic provinces are apparent in the shield. The Dom Feliciano Belt has two domains in terms of radioelements K, Th, and U. This belt includes granitic rocks of the Florianópolis Batholith, Brusque Group schists, and Itajaí Basin of sedimentary and volcanic rocks. The Luís Alves Craton has mostly the Santa Catarina Granulitic Complex and other gneisses. The craton has patches of high emission rates and extends to the northeastern extreme of the studied area with a high-contrast magnetic signal in most of the unit. The Ribeira Belt also has high in gammaspectrometric images, although less homogeneous than the Dom Feliciano Belt. This belt contains granitic complexes, gneisses, and schists and has a low magnetic signal with patches of high analytical signal amplitude. Shear zones delimit different geotectonic units, but are also significant in the Ribeira Belt. The Luís Alves Craton is the most complex unit, as seen in ternary K + eTh + eU images, requiring the future discrimination of small features. This novel study of the Brazilian Shield based on new geophysical data supports the classification of the proposed main geotectonic units. [ABSTRACT FROM AUTHOR]