TEM Investigation of Anorthite Used in Weathering Experiments
EMSL Project ID
1989
Abstract
We haveperformed weathering experiments on anorthite (An98) from Miyake-jima, Tokyo, Japan. Samples [(010) and (001) surfaces] were treated up to 168 hours in 0.001 N perchloric acid. The pristine and reacted surfaces were studied with vertical scanning white light interferometry. This technique allows to characterize and quantify the surface topography on the angstrom to nanometer scale (e.g., Luttge et al. 1999). As a result of the weathering process, we found etch pits that show typically two different morphologies. Reaction rate measurements also show that the two types of etch pits develop quite differently over time. We propose to investigate the samples with TEM techniques at PNNL. The goal is to search for dislocations and characterize them. We hope to link our results obtained from interferometer measurements with (different) types of etch pits. If succesful, this will deepen our understanding of the dissolution mechanism and etch pit formation in anorthite feldspars. Therefore, the results of these measurements will help us to interpret the reaction rate of feldspar weathering. Samples were already provided (about a year ago during my visit at EMSL. We have discussed the project with Drs. Yufei Gao and Jim Amonette. I would appreciate your help and collaboration.
Project Details
Project type
Exploratory Research
Start Date
2000-06-02
End Date
2000-06-30
Status
Closed
Released Data Link
Team
Principal Investigator