Experiences from motorized GPR surveys in Iceland

Motorized multi-channel GPR investigations in Iceland in July 2022 showed great potential for large-scale archaeological geophysical surveys. Investigations on selected sites demonstrated effective fieldwork opportunities with excellent signal penetration through thick layers of ash and sand and very good contrast of turf houses towards the surrounding soil. Although Iceland has very challenging landscapes, many places are perfect suitable for motorized surveys making them very efficient for landscape archaeological investigations

A semi-autonomous driverless geophysical survey system for efficient large-scale high-resolution archaeological prospection

This research and development project aims to evaluate the feasibility of conducting large-scale autonomous ground penetrating radar (GPR) surveys. An electric autonomous implement carrier was used to integrate a 22-channel GPR array. This innovative approach shows promise for advancing GPR survey capabilities in the future

How much rain is too much for a GPR survey? Results of the Borre Monitoring Project

Soil moisture variation is complex and depends on a range of factors, which complicates the formulation of recommendations for GPR surveys. Low amounts of soil moisture produced GPR data of higher quality. However, precipitation rates as well as chronological sequence of precipitation/thawing processes and the GPR survey are of importance. Winter months can offer favorable conditions for GPR surveys if temperatures remain negative over a prolonged time period, allowing for frost to build in the ground. Results of the Borre Monitoring Project (BMP) are valid only for sites with similar settings as Borre; the monitoring approach, however, can be transferred to larger regions with more representative sites

FOU-PROSJEKTET "ARKEOLOGI I VEIEN?" SLUTTRAPPORT Bruk av geofysiske undersøkelsesmetoder ved arkeologisk registrering i forbindelse med veiutbyggingsprosjekter

Statens vegvesen Vegdirektoratet og Norsk institutt for kulturminneforskning startet i 2012 et forsknings- og utviklingsprosjekt som ved sin avslutning har pågått i hele 10 år. Prosjektet har omhandlet bruk av inngrepsfrie avanserte metoder for registrering av arkeologiske kulturminner i forbindelse med veiutbyggingsprosjekter. Prosjektet «Arkeologi i veien?» (AiV-prosjektet) har hatt som formål å teste ut hvorvidt høyteknologiske fjernmålingsmetoder som geofysikk, LIDAR, samt satellittbilder og flyfoto kan supplere og eventuelt erstatte noen av de tradisjonelle arkeologiske metodene som brukes til registrering av kulturminner i forkant av større veiprosjekter, og på den måten begrense områder som skal sjaktes eller undersøkes på annen, konvensjonell måte. AiV-prosjektet har i perioden 2012–2020, med gode resultater, testet ut bruken av geofysiske undersøkelsesmetoder ved flere prosjekter i hele landet. Prosjektet fikk en videreføring gjennom VEMOP prosjektet (The Vestfold monitoring project. Environmental factors in minimal-invasive Cultural Heritage Management) i Vestfold- og Telemark fylke, og blir dermed ikke endelig sluttført før 2022

The influence of environmental factors on the quality of GPR data : the Borre Monitoring Project

The Borre Monitoring Project investigated how environmental factors, in particular, precipitation and soil moisture variation as well as different soil and sediment types, affect the quality of GPR data collected for archaeological purposes. To study these questions, regular GPR surveys were conducted over a period of 14 months across a test area covering a hall building at the Iron and Viking Age site of Borre in Norway. In order to obtain in situ measurements of environmental factors relevant for electromagnetic wave propagation including volumetric water content, bulk electrical conductivity, ground temperature, and precipitation, three monitoring stations were erected at the test site. Soil and sediment samples taken from the profiles at the respective monitoring stations were analysed to gain a basic description of their physical and chemical properties. Twelve GPR surveys were conducted roughly once a month between August 2016 and September 2017 and the results clearly indicated differences in the quality of the data collected. To better understand the underlying causes for this variation, GPR data were compared against and integrated with the in situ measurements gathered using the monitoring stations. The results of this analysis emphasised the benefit of dry conditions, which, if prevailing over a longer period of time, proved to generate GPR data of the highest quality. Seasonality could not be attested; instead, data quality was governed by small-scale weather patterns, where the time and intensity of rainfall events prior to the surveys as well as sudden changes in air temperature played a decisive role. While the results of this study are only valid for sites with similar settings such as Borre, they emphasise the importance of considering the environmental factors during all stages of a GPR survey and highlight the need for further studies investigating other settings