High-resolution Ground-penetrating Radar Research Articles

Identification of subsurface archaeology at Mutaredh, United Arab Emirates, using ground penetrating radar

The United Arab Emirates holds great historical importance, as evidenced by many archaeological sites, such as the Jebel Hafit Tombs and the Hili Archeological Park in Al Ain. At the western edge of Mutaredh Oasis, a major new archaeological site was discovered in 2023 during a construction project. Several important archeological features have been documented, including an earthen mosque and boundary walls, Iron Age irrigation systems, and a circular stone tomb dating to the Bronze Age. However, the eastern edge of the Mutaredh site has remained unexplored to date. Ground Penetrating Radar (GPR) has been proven to be a successful method in mapping archaeological remains. Accordingly, a high-resolution GPR survey was carried out to identify the continuity of the unearthed archeological elements and delineate new unexplored features. A comprehensive 3D model of buried archaeological features was constructed using the acquired high-resolution GPR data in the eastern part of the Mutaredh site. Several selected anomalies have been observed, similar to the uncovered features in the western part of the Mutaredh site and structures documented in other nearby archaeological sites. The geometry and extension of these anomalies have enabled the possible identification of a further two Bronze Age circular tombs, as well as the delineation of a system of water channels (falaj), and irrigation networks with tree pits from the Iron Age. Moreover, walls probably belonging to the Late Islamic Age are identified. These findings suggest that Mutaredh has been a site of intensive human activity from the Bronze Age through to the Late Islamic period. Given the density of identified anomalies, further significant features are anticipated to lie buried in the immediate surrounding areas, promising continued insights into the area’s rich archaeological heritage. The findings of this study may guide archaeologists to specific locations and assist in selecting the most appropriate excavation techniques for the verification stage.

Experimental validation of the horizontal resolution improvement by ultra-wideband metasurfaces for GPR systems

Achieving high horizontal resolution is crucial for general non-destructive testing (NDT) applications, and in the domain of ground penetrating radar (GPR), it can be more challenging due to inefficient transmissions of electromagnetic waves into and through complex material under test (MUT). In this study, we showcase the validation results of our recently designed ultra-wideband metasurface (UWM) in improving the horizontal resolution for GPR B-Scan images. This UWM has an ultra-wide working frequency band (100%) from 1 to 3 GHz, in which high-frequency GPR signals can be enhanced and transmitted into MUT. Our fourteen-day consecutive GPR experiments demonstrate that two buried pipes with an edge-to-edge spacing of 8 cm that are hard to distinguish by traditional GPR surveys can be visually identified by depositing the UWM atop the MUT. The underlying mechanism is the sustained and improved transmission of high-frequency signals into the MUT, enabled by the removal of transmission coupling loss by the UWM at the air–MUT interface and the resulting enhanced transmission of more high-frequency components. Our simulations also provide quantitative analysis of such enhanced behavior with a nominal transmittance increase of 30% ∼50%. We believe the horizontal resolution improvement enabled by UWM will open a new corridor for high-resolution GPR system design.

Reconstruction of High-Resolution 3D GPR Data from 2D Profiles: A Multiple-Point Statistical Approach

Ground-penetrating radar (GPR) is a popular geophysical tool for mapping the underground. High-resolution 3D GPR data carry a large amount of information and can greatly help to interpret complex subsurface geometries. However, such data require a dense collection along closely spaced parallel survey lines, which is time consuming and costly. In many cases, for the sake of efficiency, a choice is made during 3D acquisitions to use a larger spacing between the profile lines, resulting in a dense measurement spacing along the lines but a much coarser one in the across-line direction. Simple interpolation methods are then commonly used to increase the sampling before interpretation, which can work well when the subsurface structures are already well sampled in the across-line direction but can distort such structures when this is not the case. In this work, we address the latter problem using a novel multiple-point geostatistical (MPS) simulation methodology. For a considered 3D GPR dataset with reduced sampling in the across-line direction, we attempt to reconstruct a more densely spaced, high-resolution dataset using a series of 2D conditional stochastic simulations in both the along-line and across-line directions. For these simulations, the existing profile data serve as training images from which complex spatial patterns are quantified and reproduced. To reduce discontinuities in the generated 3D spatial structures caused by independent 2D simulations, the target profile being simulated is chosen randomly, and simulations in the along-line and across-line directions are performed alternately. We show the successful application of our approach to 100 MHz synthetic and 200 MHz field GPR data under multiple decimation scenarios where survey lines are regularly deleted from a dense 3D reference dataset, and the corresponding reconstructions are compared with the original data.

Geophysical and chemical characteristics of peatland in coastal wetland, southern Thailand

Peatlands, as an important carbon sink, store a large amount of atmospheric carbon that is vulnerable to becoming a carbon emission source due to the disturbance of the peat layer by natural and anthropogenic processes. The Kuan Kreng peat swamp forest is the second largest peatland in Thailand and is in coastal wetland serving for carbon stock in the subsurface. To assess carbon stock in peatland, the thickness and distribution of the peat layer are necessary. This study determines physical and chemical characteristics of the peatlands in the coastal wetland, southern Thailand by conventional core study and geophysical surveys, including ground penetrating radar (GPR) and electrical resistivity imaging (ERI). There is a significant relationship between chemical and physical properties from the peat layer, which is useful to approximately predict the physical properties and peat layers in the geophysical profiles. The resistivity profiles exhibit high resistivity response, peat between 21.9 and 145.0 ohm-m, interpreted as the peat layers in the shallow subsurface. The high resolution GPR profiles provide an average GPR velocity in peat of 0.040 m/ns and a relative dielectric constant of 54.9 for the peat layers. The peat layer is characterized by a high amplitude of reflection in the GPR profiles. The thickness of the peat layers was estimated from the geophysical surveys and the drilling cores having an average thickness of 18 cm. Average values of bulk density (0.19 g/cm3) and TOC (31.18 wt. %) from the drilling core samples are used to calculate the carbon density in the peat layers giving a result of 59.24 Kg C/m3. Hence, the carbon stock at the Kuan Kreng peat swamp forest is estimated at least 7.53 megaton carbon, which is much higher than aboveground biomass carbon in this area. The innumerably high amount of carbon stock could raise awareness of peatland disturbances.

A Newly Developed Tool for the Post-Processing of GPR Time-Slices in A GIS Environment

Ground-penetrating radar (GPR) is a precious and reliable research tool broadly used in archaeology because of its capacity to produce three-dimensional data about features preserved underground, such as buildings, infrastructures, and burials, as well as building rubble. GPR data (time-slices) management and exploitation in Geographic Information Systems (GIS) is mostly limited to the visualization and the manual interpretation and mapping of separate single time-slices. This study presents a newly developed plug-in designed to automatically post-process GPR time-slices in a GIS environment, to identify anomalies, and to produce a synchronic view of them. This map product, when combined with a DTM, results in a 2D map of subsurface anomalies which shows the absolute height of features above sea level, thus offering a comprehensive view of the three-dimensional configuration of the subsurface features identified. The paper illustrates the pixel-based processing chain of the plug-in and the results of the tests carried out in the case study of the Roman town of Falerii Novi (Italy), on the basis of high-resolution open access GPR data recently collected by the University of Cambridge and Ghent.

Ground Penetrating Radar (GPR) survey over a melting blue ice area (BIA) at the south of Schirmacher Oasis, Dronning Maud Land, East Antarctica

A blue ice area (BIA) is located in Dronning Maud Land, East Antarctica between Schiermacher Oasis (SO) and Ulthat mountain ranges. High-resolution ground-penetrating radar (GPR) survey has been carried out in the northern boundary of the BIA surrounded by Schirmacher Oasis (SO), Shivalinga and Veteheia nunataks to examine if the BIA in the area is wind-induced or melt-induced in nature. GPR study reveals that the glacier in this part of BIA is warm and showing prominent signatures of subsurface melting in the vicinity of the nunataks and other exposed rock masses. The signatures of bottom warming also have been detected in few profiles which are in agreement with the drilling results in nearby areas. Melting signatures vary over the area depending on the distances from the exposed rocks and proximity of subglacial bedrock topography. The results indicate the possible higher heat supply by the exposed rock mass to the BIA. Folding of the internal layers and the presence of two firn pockets also have been observed near the nunatak Veteheia. The present GPR study concludes that the survey area is predominantly melt-induced BIA. Further investigations are recommended to study the firn pockets and mass balance of the area.

When faults diverge – High resolution imaging of an intra-fault zone in an urban environment. A case study from the city of Tiberias, Israel

The presence of active faults or potentially active faults in urban settings is of great concern to city planners and developers. The high value of property within cities means that it is not always possible to avoid construction in such areas. Thus, building codes exist in order to regulate where and how to build in the vicinity of such faults. The Israeli National Building Code defines a zone of active faulting as a 200-m wide area on each side of an active or potentially active fault trace. In this area, there is a high potential for repeated activity of undetected branches or secondary faults and construction should be avoided or built with extreme safety measures in place. The current study examines an area located between two fault strands – an active and a potentially active one - in the city of Tiberias, northern Israel. The area lies outside the active fault zones defined for each strand (i.e., at a distance of more than 200 m from each fault). Eight high-resolution ground penetrating radar (GPR) profiles were collected along the streets that crisscross this area. Results show a dense series of potential fault strands that reach the base of the artificial fill that was laid down for the construction of the roads, indicating potential seismic hazard in this seemingly “safe” zone, thus raising a “red flag” for construction plans in the area. A geological study should be conducted to validate the geophysical results. This study shows the importance in conducting a geophysical site survey in tectonically active settings, even in areas that lie outside well defined zones of active faulting.

Ground-penetrating radar imaging reveals glacier's drainage network in 3D

Abstract. Hydrological systems of glaciers have a direct impact on the glacier dynamics. Since the 1950s, geophysical studies have provided insights into these hydrological systems. Unfortunately, such studies were predominantly conducted using 2D acquisitions along a few profiles, thus failing to provide spatially unaliased 3D images of englacial and subglacial water pathways. The latter has likely resulted in flawed constraints for the hydrological modelling of glacier drainage networks. Here, we present 3D ground-penetrating radar (GPR) results that provide high-resolution 3D images of an alpine glacier's drainage network. Our results confirm a long-standing englacial hydrology theory stating that englacial conduits flow around glacial overdeepenings rather than directly over the overdeepening. Furthermore, these results also show exciting new opportunities for high-resolution 3D GPR studies of glaciers.

A High-resolution GPR horizon extraction method based on local reflection and global correlation

Horizon extraction is a very basic and important part of ground penetrating radar (GPR) interpretation. Most GPR horizon extraction methods are based on local reflection of the GPR event such as the trace correlation algorithm, and hidden Markov model algorithm. These methods use only local structural characteristics of the GPR data and often fail to pick the layer correctly across discontinuous caused by faults and noise. In order to overcome shortcomings of the above methods, a novel method based on gradient structure tensor algorithm (GST) and dynamic time warping algorithm (DTW) is used in this paper to extract the horizon accurately which has been proved to be effective in the complex seismic data. GPR electromagnetic wave and seismic wave have certain similarity in kinematics and dynamics, we apply this method to realistic GPR data and prove its effectiveness.

Coherent diffraction imaging for enhanced fault and fracture network characterization

Abstract. Faults and fractures represent unique features of the solid Earth and are especially pervasive in the shallow crust. Aside from directly relating to crustal dynamics and the systematic assessment of associated risk, fault and fracture networks enable the efficient migration of fluids and therefore have a direct impact on concrete topics relevant to society, including climate-change-mitigating measures like CO2 sequestration or geothermal exploration and production. Due to their small-scale complexity, fault zones and fracture networks are typically poorly resolved, and their presence can often only be inferred indirectly in seismic and ground-penetrating radar (GPR) subsurface reconstructions. We suggest a largely data-driven framework for the direct imaging of these features by making use of the faint and still often underexplored diffracted portion of the wave field. Finding inspiration in the fields of optics and visual perception, we introduce two different conceptual pathways for coherent diffraction imaging and discuss respective advantages and disadvantages in different contexts of application. At the heart of both of these strategies lies the assessment of data coherence, for which a range of quantitative measures is introduced. To illustrate the versatility and effectiveness of the approach for high-resolution geophysical imaging, several seismic and GPR field data examples are presented, in which the diffracted wave field sheds new light on crustal features like fluvial channels, erosional surfaces, and intricate fault and fracture networks on land and in the marine environment.

High-resolution GPR survey for masonry wall diagnostics

Ground-penetrating Radar (GPR) is a non-invasive technique with increasing focus on civil-engineering applications. Referring to existing constructions, the most recent International and National Codes suggest a knowledge-based approach, which is mandatory before any structural assessment or design of interventions. The knowledge-based process includes experimental investigations aimed at the detailed geometrical and structural relief as well as to the evaluation of the materials mechanical properties. However, when dealing with built Cultural Heritage, destructive techniques should be limited or even forbidden. In this context, non-destructive investigations play a key role and their effectiveness should be further studied in relation to specific applications. To this end, Ground-penetrating Radar surveys were performed in the test site of the Laboratory of Applied Geophysics, the University of Salento, Lecce (Italy), with the aim of simulating various real-life practical applications. In particular, several objects of different materials and geometries were buried in the subsurface and a small building was built in the area using different construction techniques, among them, multi-leaf masonry walls, also called sack masonry walls, were constructed. The GPR method can detect both the presence of hidden bodies and different leafs of the walls with a relative efficiency depending on the field context, the dielectric properties of the host material, and the nature and size of the bodies. In this work, a test was planned to verify 900 and 2000 MHz antenna resolutions. The data acquired with the 2000 MHz antenna were used to estimate the mean electromagnetic wave propagation velocity in the sack masonry layers of known thickness and to understand if the inner core was filled with material other than air. The authors propose a high-resolution method to improve the velocity estimation using geometrical optics laws and the sign of the reflection coefficient in order to properly select the arrivals from different interfaces.

Beyond Amplitudes: Multi-Trace Coherence Analysis for Ground-Penetrating Radar Data Imaging

Under suitable conditions, ground-penetrating radar (GPR) measurements harbour great potential for the non-invasive mapping and three-dimensional investigation of buried archaeological remains. Current GPR data visualisations almost exclusively focus on the imaging of GPR reflection amplitudes. Ideally, the resulting amplitude maps show subsurface structures of archaeological interest in plan view. However, there exist situations in which, despite the presence of buried archaeological remains, hardly any corresponding anomalies can be observed in the GPR time- or depth-slice amplitude images. Following the promising examples set by seismic attribute analysis in the field of exploration seismology, it should be possible to exploit other attributes than merely amplitude values for the enhanced imaging of subsurface structures expressed in GPR data. Coherence is the seismic attribute that is a measure for the discontinuity between adjacent traces in post-stack seismic data volumes. Seismic coherence analysis is directly transferable to common high-resolution 3D GPR data sets. We demonstrate, how under the right circumstances, trace discontinuity analysis can substantially enhance the imaging of structural information contained in GPR data. In certain cases, considerably improved data visualisations are achievable, facilitating subsequent data interpretation. We present GPR trace coherence imaging examples taken from extensive, high-resolution archaeological prospection GPR data sets.

The Effectiveness of Large-Scale, High-Resolution Ground-Penetrating Radar Surveys and Trial Trenching for Archaeological Site Evaluations—A Comparative Study from Two Sites in Norway

The use of large-scale, high-resolution ground-penetrating radar surveys has increasingly become a part of Norwegian cultural heritage management as a complementary method to trial trenching surveys to detect and delineate archaeological sites. The aim of this article is to collect, interpret and compare large-scale, high-resolution ground-penetrating radar (GPR) survey data with results from trial trenching and subsequent large-scale excavations, and to extract descriptive and spatial statistics on detection rates and precision for both evaluation methods. This, in turn, is used to assess the advantages and disadvantages of both conventional, intrusive methods and large-scale GPR surveys. Neither method proved to be flawless, and while the trial trenching had a better overall detection rate, organic and charcoal rich features were nearly just as easily detected by both methods. Similarly, the spatial representability was similar, even though the total detection rates were lower with the GPR. This can be used as an argument in advance of integrating full-coverage GPR results into a site evaluation scheme, preferably in combination with other methods. Overall, these analyses have highlighted drawbacks and possibilities in both methods that are important contributions in understanding how to use them and integrate them in future site evaluations.

Geophysical Characterisation of the Active Fault Geometry and Trends in Tectonic Deformation in the Shallow Stratigraphy along Active Faults, South Andaman, India

Abstract A comprehensive Ground Penetrating Radar (GPR) profiling with high resolution was done and complemented with total station surveys along an active faults in the South Andaman Island (near Bathubasti) to reveal the sub-surface fault geometry and trends in tectonic deformation in shallow stratigraphy. The surface manifestation of deformation along the investigated active faults is expressed in the form of explicit tectonic scarps of various levels related to persistent tectonic uplift of the area and frontal scarps expressed in younger sediments were meticulously examined with GPR profiling. The surface displacement (scarp height) was calculated by using high resolution GPR data and total station data that may be correlated to the vertical displacement component of palaeoseismic faulting. Two active fault sites were carefully chosen for the systematic profiling with high resolution GPR profiling to examine the efficacy of GPR in elucidating the complicated near surface tectonic deformation. The surface deformation of site-1 is manifested in a form of a 6 m high abrupt tectonic scarp expressed in quaternary sediments. Site-2 is piggy back basin with corresponding pop-up structures with two antithetic scarps of 10 m height each. The high resolution GPR data vividly reveals the complicated sub-surface fault geometry and tectonic deformation in the form of an inclined and distorted radar reflections upto several meters of depth in the shallow stratigraphy and upward fault termination related to the active deformation. The high resolution GPR profiling demonstrates severe near surface tectonic deformation in the form of buckling, truncation, offsetting of recent sediments and warped radar reflections suggesting the propagation of tectonic activity in a compressive stress regime whose dynamics is related to the continuous oblique subduction of Indian plate under the Burmese micro plate.

Permittivity estimation of a shallow-layered medium using high-resolution ground-penetrating radar

ABSTRACTThis paper proposes a method of permittivity estimation using ground penetrating radar (GPR). The proposed method can estimate the permittivity of a shallow-layered medium. In the proposed method, antenna calibration is introduced to improve the vertical resolution of the GPR. The conventional surface reflection method is slightly modified to be suitable for operation at a shallow depth since the antenna calibration impacts the signal amplitude being exploited to estimate the permittivity. Simulation and experimentation examples are illustrated to confirm that the proposed method can estimate the permittivity of each layer of dielectric ground medium. Simulations were divided into two main catalogues in order to investigate the resolution improvement and estimation accuracy of the GPR. The experimentation of the GPR along with the proposed method were conducted. The experimental results showed good agreement with those obtained from the commercial dielectric prob kit.

A cross-validated three-dimensional model of an englacial and subglacial drainage system in a High-Arctic glacier

AbstractRecent speleological surveys of meltwater drainage systems in cold and polythermal glaciers have documented dynamic englacial and in some cases subglacial conduits formed by the ‘cut-and-closure’ mechanism. Investigations of the spatial distribution of such conduits often require a combination of different methods. Here, we studied the englacial drainage system in the cold glacier Longyearbreen, Svalbard by combining speleological exploration of a 478 m long meltwater conduit with a high-resolution ground penetrating radar (GPR) survey with two different centre-frequencies (25 and 100 MHz). The results yielded a 3-D documentation of the present englacial drainage system. The study shows that the overall form of englacial conduits can be detected from velocity−depth converted GPR data, and that the 3-D model can facilitate a method to pinpoint the reflections in a radargram corresponding with the englacial drainage system, although fine detail cannot be resolved. Visible reflections approximately parallel to the mapped englacial water drainage system likely result from sediment incorporated in the ice or from abandoned parts of the englacial drainage system.

Imaging of the Internal Structure of Permafrost in the Tibetan Plateau Using Ground Penetrating Radar

The distribution of the permafrost in the Tibetan Plateau has dramatically changed due to climate change, expressed as increasing permafrost degradation, thawing depth deepening and disappearance of island permafrost. These changes have serious impacts on the local ecological environment and the stability of engineering infrastructures. Ground penetrating radar (GPR) is used to detect permafrost active layer depth, the upper limit of permafrost and the thawing of permafrost with the season’s changes. Due to the influence of complex structure in the permafrost layer, it is difficult to effectively characterize the accurate structure within the permafrost on the radar profile. In order to get the high resolution GPR profile in the Tibetan Plateau, the reverse time migration (RTM) imaging method was applied to GPR real data. In this paper, RTM algorithm is proven to be correct through the groove’s model of forward modeling data. In the Beiluhe region, the imaging result of GPR RTM profiles show that the RTM of GPR makes use of diffracted energy to properly position the reflections caused by the gravels, pebbles, cobbles and small discontinuities. It can accurately determine the depth of the active layer bottom interface in the migration section. In order to prove the accuracy of interpretation results of real data RTM section, we set up the three dielectric constant models based on the real data RTM profiles and geological information, and obtained the model data RTM profiles, which can prove the accuracy of interpretation results of three-line RTM profiles. The results of three-line RTM bears great significance for the study of complex structure and freezing and thawing process of permafrost at the Beiluhe region on the Tibetan Plateau.

Archaeological Prospection with Motorised Multichannel Ground-Penetrating Radar Arrays on Snow-Covered Areas in Norway

The technical advancements of the past decade have rendered motorised, high-resolution ground-penetrating radar (GPR) investigations increasingly popular for archaeological research and cultural heritage management in Norway. However, the agricultural use of most survey areas limits the time available for fieldwork in spring and autumn and thus reduces the method’s potential. An extension of the fieldwork period into the winter season would be desirable. The project “Arkeologi i veien?” aimed to develop practical solutions for efficient motorised GPR surveys on snow and to evaluate to what extent the thickness of the snow cover affects data quality. Four sites with known archaeological remains in the ground have been investigated under snowless conditions and with snow cover. The comparative data analysis showed that GPR surveys can result in useful data even on areas covered with one metre of snow. This study shows that different temperatures and resulting variable snow conditions can have a strong effect on the quality of the generated GPR data. The possibility for GPR measurements on snow offers the opportunity to extend fieldwork into the winter period without conflicting with the growing season; however, local weather and snow conditions have to be closely observed in order to obtain useful prospection data.

Analyzing the architecture of point bar of meandering fluvial river using ground penetration radar: A case study from Hulun Lake Depression, China

The point bar is one of the most important reservoirs in a meandering depositional system, and accurately building a 3D architecture model for point bars is crucial to predict hydrocarbon distribution within the reservoir. Unfortunately, we can only obtain a qualitative description about the internal architecture of the point bar due to the limited information or the low resolution of available data (such as reflection seismic data). To build a 3D prototype point bar reservoir model, we analyze the architecture of point bars by integrating high-resolution ground penetrating radar (GPR) data and modern deposition. We found that our GPR data have five main reflection patterns (GPR facies), and GPR facies can be used to relate with architectural elements (the depositional facies and geobodies within depositional facies). The concave-down GPR facies is usually related to the abandoned channel. The continuous, subhorizontal, subparallel GPR facies is commonly related with lateral-accretion sand bodies within the point bar. The multiple stacked small-scale, discontinuous reflections GPR facies is interpreted to be shale drapes within the point bar. We further analyzed the geometry parameters of the identified channels. We found that the nonsymmetric [Formula: see text] of abandoned channel near the channel axis is related to the ratio between the curvature of channel radius [Formula: see text] and channel width [Formula: see text] ([Formula: see text]). Finally, we built two 3D channel reservoir models and our models could provide useful guidance for the architecture analysis of buried meandering fluvial reservoirs.

An integrated high-resolution geophysical and geologic visualization of a Lake Bonneville shoreline deposit (Utah, USA)

Pilot Valley, located in the eastern Basin and Range, Western Utah, USA, contains numerous shorelines and depositional remnants of Late Pleistocene Lake Bonneville. These remnants present excellent ground-penetrating radar (GPR) targets due to their coherent stratification, low-clay, low-salinity, and low moisture content. Three-dimensional GPR imaging can resolve fine-scale stratigraphy of these deposits down to a few centimeters, and when combined with detailed outcrop characterization, it provides an in-depth look at the architecture of these deposits. On the western side of Pilot Valley, a well-preserved late Pleistocene gravel bar records shoreline depositional processes associated with the Provo (or just post-Provo) shoreline period. GPR data, measured stratigraphic sections, cores, paleontological sampling for paleoecology and radiocarbon dating, and mineralogical analysis permit a detailed reconstruction of the depositional environment of this well-exposed prograding gravel bar. Contrary to other described Bonneville shoreline deposits, calibrated radiocarbon ages ranging from 16.5 to 14.3 (ka, BP) indicate that the bar was stable and active during an overall regressive stage of the lake, as it dropped from the Provo shoreline (or just post-Provo level). Our study provides a model for an ancient pluvial lakeshore depositional environment in the Basin and Range province and suggests that stable, progradational bedforms common to the various stages of Lake Bonneville are likely not all associated with periods of shoreline stability, as is commonly assumed. The high-resolution GPR visualization demonstrates the high degree of compartmentalization possible for a potential subsurface reservoir target based on ancient shoreline sedimentary facies.