An object‐based approach to support the automatic delineation of magnetic anomalies

Abstract

The intensive use of geophysics in archaeological investigations demands new ways of fast and meaningful data interpretation. With the increasing size and complexity of magnetometer data, manual identification and delineation of magnetic anomalies becomes a time‐consuming activity. In this respect, our study introduces a new approach to automate this laborious procedure, implemented as a ready‐to‐use tool within the eCognition® software. The approach relies on a multiresolution segmentation (MRS) algorithm, which is applied on a single layer containing magnetic values. Magnetic anomalies are automatically identified and delineated at three levels of scale. Magnetic anomalies are thus classified as potential archaeological features. The degree of departure from a normal distribution is adjustable at 0.5 and 1 standard deviation (SD), respectively. The approach was tested on magnetometer images of a buried medieval village in the west of Romania. The data were acquired along parallel profiles covering six squares of 100 m × 100 m each. We have deliberately selected this magnetic map because it is not the top in terms of magnetic results and it provides staggers (due to data acquisition in 100 m grids) to show that if this algorithm works on this magnetic map, it will work defiantly on those where archaeological structures/anomalies are even more regulated. The tested scenes indicated accurate results, displaying positive‐ and negative‐valued magnetic anomalies with levels of detail almost similar to manually delineated anomalies. Our approach is simple to apply. Being implemented as a customized process for the eCognition® software, the tool attached to the article repository has a significant potential to support interpretation of any type of image obtained through geophysical measurements and we consider it an aid for large‐scale surveys.

Geographic Disparity in Machine Intelligence Approaches for Archaeological Remote Sensing Research

“…In the same amount of time, automated methods were used to evaluate over 2000 km 2 with similar levels of success [14]. Recent MI developments by archaeologists have released code and software to permit for replication and use by other researchers [4,80], and this must become standard practice.…”

Archaeogeophysical exploration in Neuss‐Norf, Germany using electrical resistivity tomography and magnetic data

“…A number of geophysical techniques have been used to investigate archaeological sites, including direct current resistivity, magnetic, ground‐penetrating radar (GPR), electromagnetic, microgravity and seismic methods (Jeng et al ., 2003; Rizzo et al ., 2005; Batayneh et al ., 2007; Müller et al ., 2009; Zhao et al ., 2013; Rabbel et al ., 2014; Martinez et al ., 2015; Di Maio et al ., 2016; Gündoğdu et al ., 2017; Akca et al ., 2019; Florio et al ., 2019; Křivánek, 2019; Lulewicz et al ., 2019; Orlando et al ., 2019; Yilmaz et al ., 2019). Ultimately, the adoption of geophysical techniques in archaeology is not only to the advantage of archaeologists, but also constitutes a precious resource for decision‐makers involved in the protection of human heritage (Hegyi et al ., 2019).…”

“…Geophysical methods can therefore serve as fast, cheap and nondestructive tools in determining locations for prospective excavation (Reynolds, 2011;Gündogdu Figure 1 Location map of the study area. The yellow rectangle marks the location of the archaeological site resource for decision-makers involved in the protection of human heritage (Hegyi et al, 2019).…”

Object-Based Image Analysis of Ground-Penetrating Radar Data for Archaic Hearths

“…there are few examples in the literature, however, that apply a semi-automated OBIA approach to geophysical data in the field of archaeology. A handful of studies have successfully implemented OBIA using magnetometry data to identify archaeological features (e.g., [3,[33][34][35]), while fewer have applied this to Ground-Penetrating Radar (GPR) data (e.g., [3,36,37]).…”