Additional file 6 of High spatial resolution magnetic mapping using ultra-high sensitivity scanning SQUID microscopy on a speleothem from the Kingdom of Tonga, southern Pacific
Creators: name: Fukuyo, Naoto
name: Hirokuni Oda
name: Yokoyama, Yusuke
name: Clark, Geoffrey
name: Yuhji Yamamoto
Publisher: name: figshare
Year: 2021
Subjects: subject: Biochemistry
subject: 29999 Physical Sciences not elsewhere classified
subject: FOS: Physical sciences
subject: FOS: Physical sciences
subject: Biotechnology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: FOS: Earth and related environmental sciences
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: FOS: Chemical sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: FOS: Biological sciences
subject: Cancer
subject: Inorganic Chemistry
subject: Science Policy

description: Additional file 2: Figure S2. We conducted measurements of three components of magnetization with a superconducting rock magnetometer (SRM) in GSJ-Lab, AIST, on the thin section after SSM measurement at each demagnetization step. Figure S2a shows a setup of the experiment, and Fig. S2b shows the photo indicating the size of the thin section (thickness = 0.2 mm). Figure S2c shows the sensor response of the cross-Sect. (31 mm × 0.2 mm) calculated with a software response (Xuan and Oda, 2019). Nine tensor components of the effective length corresponding to the AAC1 sample (37 mm) were also calculated using the sensor response (shown in Figure S2c). Three components of the magnetization after the correction of the sensor response was calculated from the raw magnetic moment values and the tensor components using the formulae 2 in Xuan and Oda (2019). Deconvolution was not conducted, because the cross-section of the speleothem sample is not uniform along the thin section. Figure S2d shows an estimated magnetization for NRM before demagnetization (top: declination, middle: inclination, bottom: total intensity, and each component). Figure S2e–d shows demagnetization diagrams of magnetization picked up from positions at 1 cm and 3 cm as representative of upper and lower parts of the sample, respectively. S2e is the normalized intensity versus AF steps, S2f and S2g are vector endpoint diagrams for positions 1 cm and 3 cm, respectively. Solid (open) circles correspond to projection onto a horizontal (vertical) plane. It is clear that 80% of the magnetization of the sample is removed by AF demagnetization up to 30 mT. The components removed by AF demagnetization (AFD) at 5 mT indicate that this component is different from the component removed from 5 to 30 mT AFD. The second measurement of NRM with the SSM was used in this study conducted after the measurement with the SRM, which is different from the other AF step measurements. The sample could have been exposed to the Earth's magnetic field during transportation to the SRM located in another building, which suggests the acquisition of laboratory-induced viscous remanent magnetization after the 1st SSM measurement and before the SRM measurement.