Advantages to Using the Pseudogravity Transformation to Aid Edge Detection of Total Field Archaeomagnetic Datasets
2011; Wiley; Volume: 18; Issue: 2 Linguagem: Inglês
10.1002/arp.408
ISSN1099-0763
AutoresS. Cheyney, I. Hill, Neil Linford,
Tópico(s)Geomagnetism and Paleomagnetism Studies
ResumoArchaeological ProspectionVolume 18, Issue 2 p. 81-93 Special Issue Article Advantages to Using the Pseudogravity Transformation to Aid Edge Detection of Total Field Archaeomagnetic Datasets S. Cheyney, Corresponding Author S. Cheyney [email protected] Department of Geology, University of Leicester, University Road, Leicester, LE1 7RH UKS. Cheyney, Department of Geology, University of Leicester, University Road, Leicester, LE1 7RH, UK. E-mail: [email protected]Search for more papers by this authorI. Hill, I. Hill Department of Geology, University of Leicester, University Road, Leicester, LE1 7RH UKSearch for more papers by this authorN. Linford, N. Linford Geophysics Team, English Heritage, Fort Cumberland, Eastney, Portsmouth, PO4 9LD UKSearch for more papers by this author S. Cheyney, Corresponding Author S. Cheyney [email protected] Department of Geology, University of Leicester, University Road, Leicester, LE1 7RH UKS. Cheyney, Department of Geology, University of Leicester, University Road, Leicester, LE1 7RH, UK. E-mail: [email protected]Search for more papers by this authorI. Hill, I. Hill Department of Geology, University of Leicester, University Road, Leicester, LE1 7RH UKSearch for more papers by this authorN. Linford, N. Linford Geophysics Team, English Heritage, Fort Cumberland, Eastney, Portsmouth, PO4 9LD UKSearch for more papers by this author First published: 12 May 2011 https://doi.org/10.1002/arp.408Citations: 16Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat ABSTRACT Magnetic surveys are becoming increasingly common on archaeological sites due to the amount of data that can be collected rapidly in a non-invasive manner. Owing to their relatively low cost compared with excavation they commonly provide the only dataset that covers an entire archaeological site, which can then be used to target other surveys and excavations to areas of interest. Typically interpretation is done visually using optimized images of the raw data, which when dealing with large datasets can be time-consuming and subjective. Various derivative based methods have been developed recently to aid the interpretation of magnetic data. A particular use for these techniques is to locate the edges of subsurface magnetic bodies, and their use is gaining popularity in aeromagnetic regional and mineral exploration surveys. Despite this they are rarely used in archaeological survey interpretation. This probably is due to the particular challenges posed as a result of the low amplitude and high-wavenumber content of archaeomagnetic surveys, where features of interest are often only slightly above the noise level. Here, it is demonstrated that when derivative-based methods are applied directly to total-field data, the high-wavenumber components of the data are amplified, making datasets difficult to interpret and often proving less useful than the total-field dataset alone. The pseudogravity transformation is a readily available tool for suppressing this bias to the high-wavenumber features and providing derivative-based results with a power spectrum comparable to the original total-field response, but with all the qualities to enhance interpretation that are obtained from using the derivative methods. Copyright © 2011 John Wiley & Sons, Ltd. References Baranov V. 1957. A new method for interpretation of aeromagnetic maps; pseudo-gravimetric anomalies. Geophysics 22(2): 359–382. 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