Prehistoric chamber tombs or geological pitfall? A multimethod case study from Ancient Aigeira with a focus on seismic full‐waveform inversion

We show an extensive multimethod geophysical study of focusing on someenigmatic subsurface structures found at Ancient Aigeira (N Peloponnes, Greece) thatcould be interpreted either as prehistoric chamber tombs or complex weatheringpatterns of the local marl–conglomerate rock sequences. It turns out that the non-seismic methods do not allow to distinguish between an archaeological and a geologi-cal origin of the observed patterns with certainty. In contrast, we demonstrate howshear-wave seismics and full-waveform inversion (FWI) can be used in archaeologicalprospection for distinguishing between these alternative essentially differentinterpretational models that are not distinguishable through nonseismic prospectiondata. The example site Aigeira is strategically well located on a hill on the NorthernPeloponnese overlooking the Corinthian Gulf and has been inhabited with occupa-tional gaps since Middle Neolithic times until the 12th to early 14th centuryCE.Magnetics, ground-penetrating radar (GPR) and electrical resistivity tomography(ERT) reveal a honeycomb-shaped anomaly pattern that could have been interpretedas a system of prehistoric chamber tombs. The time-domain SH-FWI strategy basedon a sequential inversion of low-pass and band-pass filtered data results insubsurface models for shear-wave velocity and density that accurately fits the com-plicated seismic data set.With the help of the seismic survey, we can reject the interpretationhypothesis of a prehistoric cemetery with chamber tombs and confirm that theenigmatic geophysical patterns represent a geological weathering structure thatcould be addressed as a reincised fan delta draped by reddish palaeosols

On the lion harbour and other harbours in Miletos: recent historical, archaeological, sedimentological, and geophysical research

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Geophysical prospections support the historical identification of the archaeological site at Lake Gala, Hebros/Maritsa/Meriç delta (Turkey)

Archaeological survey and combined geophysical measurements of magnetics were conducted. Geoelectrics and ground penetrating radar support the interpretation of a Roman station controlling a branch of the Via Egnatia leading to Ainos (modern Enez in Turkey). The site could be the first archaeological example of a road station in Thrace, constructed between the 1st and the 2nd century CE

‘Finding Old Sikyon’, 2015: A preliminary report

The project “Ancient Sikyon” is a cooperation between the Ephorate of Antiquities of Corinth, the National Museum of Denmark, the Danish Institute at Athens and the Institute of Geoscience of the Christian-Albrechts University of Kiel. Conceived as a five-year project, its main aim is to identify the exact location, the major features and the urbanistic development of the city, prior to its relocation in 303 BC to a plateau nearby. This, however, is intended to serve the greater purpose of answering general questions of Archaic and Classical urbanism and the structure and organization of a famous centre of art and culture in comparison with other such centres like Corinth and Athens. The first year of research has already brought important information about the topography and material culture of Ancient Sikyon, which is presented in this preliminary report

Seismische Vermessung der verlandeten Buchten des Medione und Gorgo Cotone. Hinweise zur Lage des Hafens der antiken Stadt Selinunt, Sizilien = Seismic survey of the silted bays of the medione and gorgo cotone rivers. Evidence of the location of the harbour of the Ancient City of Selinus, Sicily

Seismic survey of the silted bays of the Medione and Gorgo Cotone rivers. Evidence of the location of the harbour of the ancient city of Selinus, Sicily. The ruins of the ancient city of Selinus are located on the southern coast of Sicily on a limestone plateau bounded to the east and west by two respective silted bays or riverbeds. So far it has been impossible to archaeologically determine which of these bays served as a harbour in antiquity. In order to explore the depth structure of the silted bays, we performed two seismic surveys with shear waves, reaching penetration depths of approximately 25 m. The seismic measurements were calibrated by drillings. In th upper 15 m, the two bays differ strongly in seismic structure. The eastern bay (Gorgo Cotone valley) must be considered as a former lagoon that was connected to the sea. When the city of Selinus was founded, this lagoon was already silted at its shore, and it was banked up artificially for the construction of the eastern city quarter up to the city wall. The western bay (Modione valley) shows uniform fluvial sedimentation. A possibly artificial banking can also be found at the western foot of the city hill, dipping steeply (∼20°) from the city wall down to the Modione valley. The comparison of both locations shows that the eastern bay is a more plausible location of the harbour of Selinus, due to its protected lagoon and remains of construction

Geophysical Prospection at Miletus, 2003–2005

Der Schwerpunkt unserer geomagnetischen Messungen in Milet lag im Bereich eines vermuteten Hafengebiets östlich vom Humeitepe, im Bereich der Heiligen Straße sowie im Gebiet zwischen Kalabaktepe und der späthellenistischen Stadtmauer. Für die Arbeiten wurde ein DGPS gesteuerter Multisensor-Wagen mit acht Differenz-Fluxgate-Sensoren eingesetzt. Die Magnetik-Sensoren besaßen einen horizontalen Abstand von 500 mm. Im Osthafen liefert die Magnetik klare Hinweise auf Hafenbauwerke mit Landungsplätzen. Westlich der Heiligen Straße finden wir eine ausgedehnte Nekropole mit einem eigenen Wegesystem. Besondere Bedeutung gewinnt der Nachweis der kontinuierlichen Fortsetzung des archaischen Straßensystems über die späthellenistische Stadtmauer hinaus bis zum Kalabaktepe hin. Nördlich des Kalabaktepe finden wir eine bisher unbekannte frühchristliche Friedhofskirche. Geoelektrische Messungen können die Ergebnisse wesentlich vertiefen und erlauben so eine gezielte Ausgrabung mit optimierten Schnittflächen.Our geomagnetic survey work at Miletus, Turkey, was focused on a presumed harbour area east of Humeitepe, on the area surrounding the Sacred Way, and between Kalabaktepe and the late Hellenistic city wall. For these geomagnetic measurements we used a DGPS-controlled multi-sensor vehicle with eight differential fluxgate sensors mounted with 500 mm horizontal spacing. In the eastern port we were able to identify clear structures suggesting docks and berths. In the vicinity of the Sacred Way further graves and roadways have been found. Of highest importance is the proof of the continuation of the Archaic street system from the centre of the city as far as Kalabaktepe. An early Christian cemetery church, unknown before, has been found north of Kalabaktepe. Complementary geoelectric measurements have considerably deepened our knowledge, permitting targeted and efficient excavation

Prehistoric chamber tombs or geological pitfall? A multimethod case study from Ancient Aigeira with a focus on seismic full‐waveform inversion

We show an extensive multimethod geophysical study of focusing on some enigmatic subsurface structures found at Ancient Aigeira (N Peloponnes, Greece) that could be interpreted either as prehistoric chamber tombs or complex weathering patterns of the local marl–conglomerate rock sequences. It turns out that the nonseismic methods do not allow to distinguish between an archaeological and a geological origin of the observed patterns with certainty. In contrast, we demonstrate how shear‐wave seismics and full‐waveform inversion (FWI) can be used in archaeological prospection for distinguishing between these alternative essentially different interpretational models that are not distinguishable through nonseismic prospection data. The example site Aigeira is strategically well located on a hill on the Northern Peloponnese overlooking the Corinthian Gulf and has been inhabited with occupational gaps since Middle Neolithic times until the 12th to early 14th century ce. Magnetics, ground‐penetrating radar (GPR) and electrical resistivity tomography (ERT) reveal a honeycomb‐shaped anomaly pattern that could have been interpreted as a system of prehistoric chamber tombs. The time‐domain SH‐FWI strategy based on a sequential inversion of low‐pass and band‐pass filtered data results in subsurface models for shear‐wave velocity and density that accurately fits the complicated seismic data set. A highly heterogeneous subsurface is revealed that is characterized by linear cracks on a decimetre scale. The seismic FWI results are compared in detail with GPR, ERT and among each other. It turns out that the FWI result is consistent with each of these other geophysical methods but provides a more comprehensive subsurface characterization that it is supported by corings in addition. With the help of the seismic survey, we can reject the interpretation hypothesis of a prehistoric cemetery with chamber tombs and confirm that the enigmatic geophysical patterns represent a geological weathering structure that could be addressed as a reincised fan delta draped by reddish palaeosols.Land Schleswig‐Holstein http://dx.doi.org/10.13039/100018877Institute of Aegean Prehistory (INSTAP) http://dx.doi.org/10.13039/100001182Ephorate of Antiquities of AchaiaHellenic Ministry of Culture and SportAustrian Archaeological Institute and the Austrian Academy of Science

Geological Challenges of Archaeological Prospecting:The Northern Peloponnese as a type location of populated syn-rift settings

The Northern Peloponnese is not only home of a series of ancient poleis that are being studied by archaeologists, but it is also located on the southern shoulder of the most active extensional crustal structure in the world; the Corinthian rift. This rift has shaped the Northern Peloponnese as we now see it today since the Pliocene. Normal faulting, the tectonic uplift of syn-rift sediments and sea level changes, has shaped a landscape of steps rising from the coast to the ridges in the hinterland that provides challenging conditions to a geophysical survey. Where we can find coarse grained slope and delta deposits of conglomerate on top of banks of marl on ridges and slopes, the lower marine terraces and the coastal plain as well as valleys show the protective caprock eroded and the marl covered by young alluvial deposits. These materials show only a small contrast in their magnetic properties, which reduces the importance of magnetic mapping for the archaeological prospection in this region. The human utilization of the coastal plain and the urban areas pose additional challenges. These challenges have been overcome through various approaches that are shown in exemplary case studies from Aigeira and Sikyon. Whereas a combination of magnetic mapping and ground-penetrating radar (GPR) works very well on the ridges and along the slopes where we find coarser sediments in addition to the magnetic mapping, it is not suitable in the coastal plain due to the attenuating properties of the alluvial sediment. Here, electrical resistivity tomography (ERT) proved to be very successful in mapping entire parts of a settlement in great detail. Seismic soundings were also sucessfully applied in determining the bedrock depth, the detection of walls and in the question of locating the harbor basin. In the presented six exemplary case studies, the following findings were made: (1) A fortification wall and building foundations at a depth of 0.4–1.2 m on a plateau northwest of the acropolis of Aigeira was found by 400 MHz GPR. (2) A honeycomb-shaped pattern of magnetic anomalies that suggested cavities could be identified as a weathering pattern of conglomerate rocks. (3) A rock basement 2.3 m deep and remains of an enclosing wall of the Aigeira theater area were found by shear wave refraction measurements. (4) Extensive ERT surveys detected several building remains in Sikyon like a potential building and grave monuments as well as several small houses. (5) A silted-up depression in the sediments of the coastal plane located through Love wave measurements, could be taken as evidence for either a silted harbor or a navigable riverbed