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- ItemComputed Tomography (CT) of five samples of the Sutter's Mill CM2 chondrite.(2012-10-21) Ebel, Denton S.; Hill, MorganThese files supplement Jenniskens et al. (2012), a comprehensive description of the April 22, 2012 fall and the petrology of the Sutter‟s Mill CM2 chondrite breccia. Here, we present 3-dimensional scans of individual stones of this meteorite. A “Methods” document in this repository records particulars of CT (see Ebel and Rivers 2007). In the Science paper, we note that “samples SM3 and SM9 appear to contain a dominant lithology characterized by abundant 200 to 400 μm diameter clasts (chondrules or CAIs), and 0.05 - 0.15 μm metal oxide or sulfide grains. A second lithology, with higher average atomic mass (Z) matrix and more abundant clasts, appears as irregular, angular lithic fragments many mm in size. At least one metal grain ~250 μm across, was observed, surrounded by a halo ~750 μm wide, of oxidized or sulfidized metal. It is unlikely that such a grain would be sampled by random cutting. Several clasts larger than 1 mm include a low-Z spherical object that appears to be concentrically zoned, and a similar object with zoned high-Z (metal) and low-Z (silicate) layers. While the samples are fractured, and metal grains appear to be altered, no high-Z veins (e.g., FeO-rich) are observed.” And, “the meteorites studied so far exhibit a dominant, primary lithology that is the host for multiple types of exotic lithic clasts.” This lithology is evident in most of SM3. In SM3_13A, at ~30/45 sec running time, more lithic clasts appear, and a large metal-cored grain rimmed by metal sulfide or oxide, appears briefly. The oriented sample SM51 illustrates the asymmetry of fusion crust, thick on the trailing side, very thin on the leading side (top of movie), and thickest at the „lip‟ between these surfaces (image right). A slightly brighter clast (higher average Z) that intersects the leading side fusion crust at ~60/100 sec illustrates a small effect of its composition on crust thickness and composition. A clast-poor lithology is prevalent through the first half of the stack. A large metal grain is present at ~57/100. Two large chondrules appear in SM51 at ~72/100 sec, and the lithology between there and the end is rich in low Z (forsterite-rich?) spherical clasts. In SM54S, fusion crust is very prominent, sweeping left to right in the first few seconds. Several lithologies are present, perhaps four at ~11/83 sec. This sample has some low-Z terrestrial contamination, a reddish clay, that thinly fills small depressions in the sample at the bottom of the images. References Ebel, D. S. and M. L. Rivers. 2007. Meteorite 3-dimensional synchrotron micro-tomography: Methods and applications. Meteoritics and Planetary Science 42: 1627-1646. Jenniskens, P. and 69 coauthors. 2012. Radar enabled recovery of the Sutter‟s Mill meteorite, a carbonaceous chondrite regolith breccia. Science 21 December 2012: Vol. 338 no. 6114 pp. 1583-1587. DOI: 10.1126/science.1227163
- ItemExtended Digital Supplement for Abundance, Major Element Composition and Size of Components and Matrix in CV, CO and Acfer 094 Chondrites(2016) Ebel, Denton S.; Brunner, Chelsea; Konrad, Kevin; Leftwich, Kristin; Erb, Isabelle; Lu, Muzhou; Rodriguez, Hugo; Crapster-Pregont, Ellen J.; Friedrich, Jon M.; Weisberg, Michael K.These files supplement Ebel et al. (2016), a detailed exploration of the relative abundances, chemical compositions, and sizes of all types of chondrules, Ca-, Al-rich inclusions (CAI), amoeboid olivine aggregates (AOA) and matrix in CO and CV type carbonaceous chondrites. We use the collective term “inclusions” to describe all these components except matrix. These data include informational tables about the samples and mapping, x-ray emission element maps of Si, Mg, Ca, Al, Ti and Fe in each of the meteorite samples studied, derived data that allows image analysis of samples, and examples of software code used to perform image analysis. Element maps are 32-bit mosaics collected on the electron microprobe as described in the “Methods” section of Ebel et al. (2016). Maps “-xx.tif” are 8-bit masks that remove non-mapped portions of rectangular maps from consideration by software. Derived data based on outlining (segmentation) of inclusions includes maps “-GSclasts.tif” in which each type of inclusion has a different grayscale as per Tab-C of this supplement. Files “-IJdraw.tif” document the centers of mass of each segmented object, output from the ImageJ software (see reference in Ebel et al. 2016). Files “-IJresultsC.csv” (csv are comma-separated values in ASCII) tabulate the centers of mass (CofM) of each segmented object, output from the ImageJ software, and these CofM are manually corrected for CofM that fall in the matrix or mask, or in a nearby object.Files “-rgbTab.csv” list every inclusion, filtered for artifacts, with the Red-Green-Blue color combination of that inclusion in “-rgbClasts.tif”, and the minimum and maximum x and y of a bounding box around that inclusion. Other information includes the type of inclusion (originally assigned by inspection) and the computed area of each inclusion. With these data, it is possible to address rapidly and uniquely every pixel in any particular inclusion, and to then reference that pixel in all of the element maps. It is critical in this work that all the maps and derived mappings have identical x-y dimensions. Data are arrange in four directories (folders): BSE holds back-scattered electron maps of all samples for which BSE were collected, RGB holds red-green-blue composites in Mg-Ca-Al, and Si-Ca-Fe, CO holds all maps and derived data for CO chondrites, and CV holds the same for the CV chondrites. Five tables are provided, with captions in the table files. Tab-A lists samples, Tab-B reproduces Ebel et al. (2016) Table 8, Tab-C lists grayscale color equivalences used for “-GSclasts.tif”, Tab-D through Tab-F itemize all inclusions (see also “-rgbTab.csv” files) and the total element counts in each pixel in each inclusion, for CO, Allende and non-Allene CV chondrite samples, respectively. These data, with appropriate averaging and manipulation, are the basis for most of the figures and tabulated data presented in Ebel et al. (2015). Note that mapping conditions (dwell time and current) must be corrected among data sets to accurately compare element counts collected under different conditions. A program written for IDL is provided, ClastCode-EbelEtal2015.pro (ASCII), that can be used to perform many of the image processing and analysis tasks described in the paper, using the digital data provided in this Extended Digital Supplement. This code is not guaranteed to work perfectly, however, it provides the basic algorithmic procedures used for much of the image analysis work reported.
- ItemField Guide for the Geology of Central Park and New York City(American Museum of Natural History., 2022) Jaret, Steven J.; DiPadova, E.; Spaeth, Lynsey; Yuan, Victoria; Smith, Riley; Randle, David; Hammond, Keiji G.; Tailby, Nicholas; Ebel, Denton S.Teachers guide for geology of Central Park. Supplement to: Jaret, S. J., et. al. (2021). Geology of Central Park, Manhattan, New York City, USA: New geochemical insights. Geological Society of America bulletin. https://doi.org/10.1130/2020.0061(02)
- ItemOnline Materials for Metal-rich Chondrules in Renazzo-group Carbonaceous Chondrites as Associated with the PhD Dissertation of Ellen J. Crapster-Pregont (Constraining the Chemical Environment and Processes in the Protoplanetary Disk: Perspective from Populations of Calcium-and Aluminum-rich Inclusions in Ornans-group and Metal-rich Chondrules in Renazzo-group Carbonaceous Chondrites)(2019-06) Crapster-Pregont, Ellen J.All of the files herein are supporting data and information from the dissertation completed by Ellen Crapster-Pregont as part of the requirement for a PhD in geochemistry from Columbia University. This dissertation research was advised by Dr. Denton Ebel and the defense committee consisted of Drs. Terry Plank, Dave Walker, Jon Friedrich, and Ben Bostick. These files are associated with the portion of the dissertation that addresses metal nodules in Renazzo-group carbonaceous chondrites, specifically Acfer 139 (chapter 4 and appendix E in the dissertation). The following files represent digital copies of the data used to create the plots, figures, and interpretations found within the dissertation. Data range from electron probe microanalyzer element x-ray intensity maps to electron backscatter diffraction data to 3D visualization generated using computed tomography (CT). Detailed descriptions of the contents of each file can be found in “file_descriptions”. See 'show full item record' for the citation and DOI of a full copy of this dissertation.
- ItemOnline Materials for Populations of Calcium-and Aluminum Inclusions and Rare Earth Elements in Ornans-group Carbonaceous Chondrites as Associated with the PhD Dissertation of Ellen J. Crapster-Pregont (Constraining the Chemical Environment and Processes in the Protoplanetary Disk: Perspective from Populations of Calcium-and Aluminum-rich Inclusions in Ornans-group and Metal-rich Chondrules in Renazzo-group Carbonaceous Chondrites)(2019-06) Crapster-Pregont, Ellen J.All of the files herein are supporting data and information from the dissertation completed by Ellen Crapster-Pregont as part of the requirement for a PhD in geochemistry from Columbia University. This dissertation research was advised by Dr. Denton Ebel and the defense committee consisted of Drs. Terry Plank, Dave Walker, Jon Friedrich, and Ben Bostick. The accompanying files are associated with the portion of the dissertation that addresses refractory inclusions and rare Earth elements in various components in Ornans-group carbonaceous chondrites (chapters 1 through 3 and appendices A through D in the dissertation). The following files represent digital copies of the data used to create the plots, figures, tables, and interpretations found within the dissertation. Data range from electron probe microanalyzer element x-ray intensity maps to LA-ICP-MS concentrations to modal phase maps. Detailed descriptions of the contents of each file can be found in “file_descriptions”. See 'show full item record' for the citation and DOI of a full copy of this dissertation.
- ItemRaman and Infrared Microspectroscopy of Experimentally Shocked Basalts(2020-01) Johnson, Jeffrey R.; Jaret, Steven J.; Glotch, Timothy D.; Sims, Melissa
- ItemSupplemental Online Material for 'Comparison of the Murchison CM2 and Allende CV3 Chondrites'(2020) Fendrich, Kim V.; Ebel, Denton S.Supplemental Online Material for 'Comparison of the Murchison CM2 and Allende CV3 Chondrites'
- ItemSupplemental Online Material for 'Formation of chondrules and matrix in Kakangari chondrites'(2020-06-14) Barosch, Jens; Ebel, Denton S.; Hezel, Dominik C.; Alpert, Samuel; Palme, HerbertSupplemental Online Material for 'Formation of chondrules and matrix in Kakangari chondrites (Earth and Planetary Science Letters 542, 15 July 2020, 116286, 11pp, https://doi.org /10.1016/j.epsl.2020.116286)
- ItemSupplemental Online Material for 'Petrology of the opaque assemblages in unequilibrated ordinary chondrites'.(2021-02-05) Alpert, Samuel P.; Ebel, Denton S.; Weisberg, Michael K.; Neiman, Jeremy R.Supplemental Online Material for Alpert, et. al. Petrology of the opaque assemblages in unequilibrated ordinary chondrites, Meteoritics & Planetary Science, 56, Nr 2, 311–330 (2021) doi: 10.1111/maps.13619
- ItemSupplementary material: Chondrules reveal large-scale outward transport of inner Solar System materials in the protoplanetary disk(2020) Williams, Curtis D.; Sanborn, Matthew E.; Defouilloy, Céline; Yin, Qing-zhu; Kita, Noriko T.; Ebel, Denton S.; Yamakaw, Akane; Yamashita, Katsuyuki (Proc. National Acad. Sci, 2020)Methods and Petrographic Descriptions of Selected Chondrules. Petrographic data on each of ten Allende and nine Karoonda chondrules includes tomographic imaging (CT) of each chondrule in its entirety; electron microprobe (EMP) x-ray intensity maps of polished sections of chondrule fragments, in major and minor elements for 18 chondrules; and quantitative EMP analyses of olivine, pyroxene, mesostasis, and other phases in each section. Quantitative analyses of many silicate phases have been performed and that data is presented in this supplement. Petrographic calculations using x-ray map data include modal analyses of the silicate portions of five chondrules (cf. Ebel et al., 2008). Measurement of the opaque/silicate volumetric ratio from 3D CT data would be feasible, as would measurement of chondrule diameters and volumes (cf. Ebel and Rivers, 2007). Estimation of the bulk elemental composition of each chondrule would be possible from these data, perhaps as an exercise for the ambitious student. The degree of alteration of each chondrule may be estimated by inspection of BSE images, in which bright (high Z) areas toward rims show post-formation diffusion of Fe into the chondrule. The related paper can be accessed at https://doi.org/10.1073/pnas.2005235117.