Analyses of Apollo 17 Samples Using the Quantitative Microanalysis Explorer: A Web-Based Visualization Platform to Study Optical, Electron, and X-Ray Imaging Data

We have developed the Quantitative Microanalysis Explorer, or QME-Tool, a web-based platform for visualization of large imaging data sets and interrogation of quantitative elemental maps acquired by electron microprobes. Using a combination of open-source JavaScript libraries and custom scripts, the QME-Tool can be used to quickly identify interesting mineral and lithologic phases in a sample by comparing backscattered-electron (BSE), optical, and X-ray images, extract quantitative chemical composition in regions from electron-probe microanalysis (EPMA) stage maps, and easily share data and sample locations with colleagues. We have used the QME-Tool to study regolith contained in 12 petrographic thin sections of the Apollo 17 double-drive tube 73001/2 as part of the Apollo Next Generation Sample Analysis (ANGSA) Program. As an example of the utility of the QME-Tool, we have characterized a ∼500 × 750 μm basaltic lithic clast located in the 73002,6016 polished thin section, using a BSE image, quantitative EPMA stage maps, optical reflected light, and transmitted light in both plane-polarized and crossed-polarized images. In addition to non-destructive quantitative composition extraction, we examine phase chemistry and compute a bulk composition for the clast as well as a supervised classification (using pre-defined mineral clusters) according to its mineralogy. The data show that in its major element composition, the clast is essentially similar to ilmenite basalt 70017. This connection is used to argue that the high-Ti basalt clasts in the drive tube originated from impacts into the valley floor and help reconstruct the emplacement mechanism of the light mantle deposit.