Amanda Chen

All Publications

• Shock compression of FeOOH and implications for iron-water interactions in super-earth magma oceans. Nature communications Zhang, Y., Bali, K., Dorn, C., Ravasio, A., Yang, H., Pandolfi, S., Chen, A. J., Wei, X., Libon, L., Che, Q., Zheng, D., Boulard, E., Benuzzi-Mounaix, A., Lee, H. J., Galtier, E., Czapla, N. A., Sokaras, D., Alonso-Mori, R., Gleason, A. E., Shim, S. H., Morard, G., Mao, W. L. 2025

  Abstract

  Iron(Fe)-water reactions in a magma ocean can influence water storage and density of planets. These reactions can form Fe-O-H phases, whose density, melting, and electronic properties at planetary interior conditions are important for informing planetary models. Here, we study natural goethite (α-FeOOH) that is shock-compressed along its principal Hugoniot. Analysis of our velocity interferometer system for any reflector (VISAR) results extends the equation of state to over 800 GPa. X-ray diffraction and VISAR reflectivity results indicate the onset of melting occurs at ~95 GPa with complete melting by 166 GPa, which may be relevant to low seismic velocity anomalies observed above the core-mantle boundary. Analysis of X-ray emission spectroscopy results up to 285 GPa shows the spin crossover of Fe, with dominantly low spin Fe above ~265 GPa in the melt, supporting formation of dense basal magma oceans in terrestrial planets. Using our measured FeOOH densities, we model planetary interiors up to 10 Earth masses. Assuming FeOOH forms via iron-water reactions, the radius decreases by up to 28%, while the density increases by up to 165% compared to the unreacted case, providing an avenue to investigate water storage and evolution in super-Earths and sub-Neptunes.

  View details for DOI 10.1038/s41467-025-67845-8

  View details for PubMedID 41455714

• SEDIMENTATION PATTERNS IN THE THREE BASINS OF WALDEN POND, CONCORD, MASSACHUSETTS, USA: A MULTIPROXY APPROACH TO DECIPHER ENVIRONMENTAL TRENDS, ANTHROPOGENIC IMPACTS, AND REGIONAL EVENTS OF THE LAST 800 YEARS JOURNAL OF SEDIMENTARY RESEARCH Monecke, K., Hubeny, J., McCarthy, F. M. G., Alderson, A., Boyce, J. I., Brabander, D. J., Veresh, R. K., Chen, A. J., Knights, C., Nishimoto, M., Passaretti, M., Pilkington, P., Riddick, N. L. 2025; 95 (4): 605-626

  View details for DOI 10.2110/jsr.2024.110

  View details for Web of Science ID 001532168000001

• Synchrotron Microanalytical Characterization and K/Ar Dating of the GL-O-1 Glauconite Reference Material at the Single Pellet Scale and Reassessment of the Age of Visually Mature Pellets MINERALS Hemming, S. R., Liu, T., Northrup, P., Nicholas, S., Rasbury, E., Chen, H., Warden, A., Chen, A., Li, R., Tappero, R., Cox, S. E., Everard, J., Wang, S., Deluca, M., Bostick, B., Halliday, A. N. 2023; 13 (6)

  View details for DOI 10.3390/min13060773

  View details for Web of Science ID 001017399600001