Carbonate Nanoparticles Formed by Water–Rock Reactions in Groundwater: Implication of Carbonate Rock Weathering in Carbonate Aquifers
Year: 2024
Type: article
Abstract: Carbonate rocks are highly reactive and exhibit higher ratios of chemical weathering compared to most other rock types. A chemo-mechanical mechanism, which is particularly effective in groundwater due to higher ion concentrations, is common in fine-grained carbonates at the nanoscale. As a result, the weathering of carbonate aquifers produces a substantial number of carbonate nanoparticles (CNPs). In this study, we utilized high-resolution transmission electron microscopy (HRTEM) to analyze CNPs formed by water–rock reactions in two types of groundwater from Shandong Province, China. Our findings reveal a significant presence of naturally occurring CNPs in groundwater. The HRTEM results show that CNPs display spherical, cubic, hexagonal, and irregular shapes, with some forming aggregates. Energy-dispersive spectrometry indicates that most nanoparticles contain O, C, Ca, and Fe, with some also containing Si, Mg, S, Sr, and Cl. Selected area electron diffraction (SAED) patterns show that CNPs are mainly amorphous, with some crystalline forms. The diverse shapes and complex compositions of these CNPs suggest that they are not man-made but formed through the weathering of carbonate minerals via chemo-mechanical mechanisms. This discovery provides new insights into carbonate mineral evolution and mineralization during weathering. Given their widespread presence, CNPs in groundwater could represent the transportation of elements in the form of particles.
Source: Minerals
DOI: 10.3390/min14100980
Authors: Gang Tao, Rui Liu, Peng Zhang, Yaqin Wang, Lei Zuo, Xiaoheng Zhang
Language: English
Subfield: Geochemistry and Petrology
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,728
OpenAlex ID: W4402965069