{"id":735,"date":"2012-06-20T22:21:48","date_gmt":"2012-06-20T22:21:48","guid":{"rendered":"http:\/\/microsites.bournemouth.ac.uk\/big-dig-2012\/?p=176"},"modified":"2014-06-13T08:15:32","modified_gmt":"2014-06-13T08:15:32","slug":"day-14-geophysical-survey","status":"publish","type":"post","link":"https:\/\/microsites.bournemouth.ac.uk\/big-dig\/2012\/06\/20\/day-14-geophysical-survey\/","title":{"rendered":"Day 14 \u2013 geophysical survey"},"content":{"rendered":"<p>Today I went to a field lower down the hill from the main site where some new geophysical surveys are currently taking place.  It is due to this type of survey that our main \u2018banjo\u2019 enclosure was found.  The two main methods used are magnetometry and resistivity, both of which are non-destructive. Magnetometry is based on the principle of measuring variations the Earth\u2019s magnetic field and mapping any patterns of magnetism in the soil caused by archaeological features.  This type of survey must be carried out in non-magnetic clothing as this can create anomalies in the results.  <\/p>\n<div id=\"attachment_177\" style=\"width: 525px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/microsites.bournemouth.ac.uk\/big-dig-2013\/files\/2012\/06\/magnetometry.jpg\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-177\" src=\"http:\/\/microsites.bournemouth.ac.uk\/big-dig-2013\/files\/2012\/06\/magnetometry.jpg\" alt=\"\" width=\"515\" height=\"386\" class=\"size-full wp-image-177\" \/><\/a><p id=\"caption-attachment-177\" class=\"wp-caption-text\">Ed using the magnetometer<\/p><\/div>\n<p>Resistivity on the other hand is based on the extent to which different features resist the flow of an electrical current that is passed through the ground.  For example, ditches retain water which is a conductor of electricity, therefore the resistivity is lower.<\/p>\n<div id=\"attachment_182\" style=\"width: 525px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/microsites.bournemouth.ac.uk\/big-dig-2013\/files\/2012\/06\/resistivity.jpg\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-182\" src=\"http:\/\/microsites.bournemouth.ac.uk\/big-dig-2013\/files\/2012\/06\/resistivity.jpg\" alt=\"\" width=\"515\" height=\"349\" class=\"size-full wp-image-182\" \/><\/a><p id=\"caption-attachment-182\" class=\"wp-caption-text\">Leah, Tom and Jack using the resistivity meter<\/p><\/div>\n<p>These measurements can then be transformed into image form in order for the results to be interpreted.  First year students Will Marffy, Tom Harrison, Ben Bazley and Ed Hughes, all studying BSc Archaeology were taking part in the surveying today as well as Jack Martin-Jones, studying Prehistory and Roman Archaeology, and Leah Harding who is studying Archaeological, Anthropological and Forensic Sciences.  Michael Davis, an external field school participant, was also surveying today whilst second year students Arias Jordens and David Amor supervised.<\/p>\n<p>In the same field as the geophysical surveying, our MSc Archaeological Practice students are excavating trenches as part of their professional practice unit, Archaeological Field Investigation.  Five ditch sections are being excavated following geophysical surveying of the area.  Simon Evans is accompanied by first year assistant Alex Cadzow who is studying Archaeological, Anthropological and Forensic Sciences and they have found some Roman pottery along with some animal bones.  <\/p>\n<div id=\"attachment_178\" style=\"width: 525px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/microsites.bournemouth.ac.uk\/big-dig-2013\/files\/2012\/06\/NWF.jpg\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-178\" src=\"http:\/\/microsites.bournemouth.ac.uk\/big-dig-2013\/files\/2012\/06\/NWF.jpg\" alt=\"\" width=\"515\" height=\"386\" class=\"size-full wp-image-178\" \/><\/a><p id=\"caption-attachment-178\" class=\"wp-caption-text\">Alex and Simon excavating a ditch section<\/p><\/div>\n<p>Tom Leeds is running a second trench being excavated and is being assisted by Pooja Swali, also an Archaeological, Anthropological and Forensic Sciences first year student.  They are hoping to complete the excavation of their ditch section by the end of the week.<\/p>\n<div id=\"attachment_179\" style=\"width: 525px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/microsites.bournemouth.ac.uk\/big-dig-2013\/files\/2012\/06\/NWF1.jpg\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-179\" src=\"http:\/\/microsites.bournemouth.ac.uk\/big-dig-2013\/files\/2012\/06\/NWF1.jpg\" alt=\"\" width=\"515\" height=\"434\" class=\"size-full wp-image-179\" \/><\/a><p id=\"caption-attachment-179\" class=\"wp-caption-text\">Tom and Pooja excavating their ditch section<\/p><\/div>\n<p>Laura Boxell<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Today I went to a field lower down the hill from the main site where some new geophysical surveys are currently taking place. It is due to this type of survey that our main \u2018banjo\u2019 enclosure was found. The two main methods used are magnetometry and resistivity, both of which are non-destructive. Magnetometry is based&#8230;  <a class=\"excerpt-read-more\" href=\"https:\/\/microsites.bournemouth.ac.uk\/big-dig\/2012\/06\/20\/day-14-geophysical-survey\/\">Read more &raquo;<span class=\"sr-only\"> about Day 14 \u2013 geophysical survey<\/span><\/a><\/p>\n","protected":false},"author":272,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[6,2],"tags":[],"class_list":["post-735","post","type-post","status-publish","format-standard","hentry","category-6","category-diary"],"acf":[],"_links":{"self":[{"href":"https:\/\/microsites.bournemouth.ac.uk\/big-dig\/wp-json\/wp\/v2\/posts\/735","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/microsites.bournemouth.ac.uk\/big-dig\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/microsites.bournemouth.ac.uk\/big-dig\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/microsites.bournemouth.ac.uk\/big-dig\/wp-json\/wp\/v2\/users\/272"}],"replies":[{"embeddable":true,"href":"https:\/\/microsites.bournemouth.ac.uk\/big-dig\/wp-json\/wp\/v2\/comments?post=735"}],"version-history":[{"count":2,"href":"https:\/\/microsites.bournemouth.ac.uk\/big-dig\/wp-json\/wp\/v2\/posts\/735\/revisions"}],"predecessor-version":[{"id":823,"href":"https:\/\/microsites.bournemouth.ac.uk\/big-dig\/wp-json\/wp\/v2\/posts\/735\/revisions\/823"}],"wp:attachment":[{"href":"https:\/\/microsites.bournemouth.ac.uk\/big-dig\/wp-json\/wp\/v2\/media?parent=735"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/microsites.bournemouth.ac.uk\/big-dig\/wp-json\/wp\/v2\/categories?post=735"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/microsites.bournemouth.ac.uk\/big-dig\/wp-json\/wp\/v2\/tags?post=735"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}