Soil Physicochemical Properties and Magnetic Grain Morphology of The Batujaya Archaeological Site
Dini Fitriani, Eleonora Agustine, Annisa Eka Oktariani

Department of Geophysics, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Jawa Barat, Indonesia

Abstract

The Batujaya archaeological site, located in Karawang, is one of the oldest archaeological sites in Indonesia. Anthropogenic activities in and around the area may alter the soil characteristics. This study investigated several physicochemical properties of soils within and outside the site, including bricks used in the site^s structures. Notably, soils inside the site exhibited lower magnetic susceptibility (chiLF) values compared to those outside, while bricks showed higher chiLF values than soils. All samples had chiLF values above 10 x 10-8 m3kg-1, indicating the dominance of ferrimagnetic minerals. Bivariate analysis revealed a positive correlation between chiLF and chiFD (%) for soils within the site, suggesting pedogenic magnetic minerals, whereas soils outside the site showed a negative correlation, implying anthropogenic sources. The electrical conductivity (EC), total dissolved solids (TDS), and pH of the soils ranged from 50-2080 uS/cm, 44-1746 mg/L, and 4.6-10.1, respectively. Scanning electron microscopy (SEM) analysis revealed magnetic grains with hedral and spherule shapes, featuring various surface textures. Inductively coupled plasma optical emission spectroscopy (ICP-OES) analysis showed that the samples were dominated by aluminum (Al) and iron (Fe). Moreover, arsenic (As) and tin (Sn) were detected in soils within the site but not in those outside.

Keywords: magnetic susceptibility, Batujaya, physicochemical properties, magnetic mineral, archaeology

Topic: Earth Physics and Space Science