Vector magnetic anomaly of kilns at Sri Satchanalai Ancient City, Changwat Sukhothai

Abstract

Sri Satchanalai ancient kiln which produced the Sangkalok (ancient ceramic) around 13th to 16th century (all 800-500 years ago) were selected for measuring the ancient magnetic direction of the kiln. Two kiln i.e. kiln no.1 and kiln no.2 were studied, fluxgate magnetometer was employed and the results show that the magnetic susceptibility vary from 50-500 nT. This figure indicate that magnetic susceptibility of the kiln were high enough to be investigated. Moreover, proton magnetometer was also use. The results show that proton magnetometer step two is most suitable. The total magnetic intensity varies from 42,000-44,000 nT. Vector magnetic gradiometer was invented. It consist of three axis sensors that are x, y and z. This equipment can measured in both horizontal and vertical magnetic direction. The data from this measurement are enormous. It need special computer software to calculate and compile. The result show that there is four degrees of mis-alignment and offset about 100-200 nT from the theoretical calculation. Therefore, the newly invented vector magnetic gradiometer need to be improved both hardware (more sensitive fluxgate magnetometer) and computer solfware.