DOI: 10.5061/dryad.c59zw3rkw
title: Decoding the formation of barred olivine chondrules: Realization of numerical replication

description: Millimeter-sized silicate spherules embedded in primitive meteorites,
 namely, "chondrules", are the primary solid component of the
 early solar nebula. They exhibit distinctive solidification textures,
 formed through rapid cooling from a molten state. The formation conditions
 of these textures have primarily been inferred based on dynamic
 crystallization experiments; however, the theoretical verification of the
 solidification process has been largely neglected. Here, we conducted
 numerical simulations of the solidification of chondrule melt, and
 successfully reproduced a crystal growth pattern resembling a typical
 barred olivine chondrule texture. This pattern emerged under conditions of
 rapid cooling, exceeding 10^4 K/hr, which is significantly larger than
 those inferred experimentally. These results suggest that theories of
 chondrule formation in the nebula, which have been developed based on
 experimental results, should be re-examined.
description: # Decoding the formation of barred olivine chondrules: Realization of
 numerical replication ## GENERAL INFORMATION **Dataset overview** This
 dataset includes the numerical calculation results of this study and
 Python scripts for visualizing them. For details on the unstructured
 triangular grid used for numerical calculations, refer to the following
 related publication. **Corresponding author information** ``` Name:
 Hitoshi Miura ORCID: https://orcid.org/0000-0001-8891-1658 Affiliation:
 Graduate School of Science, Department of Information and Basic Science,
 Nagoya City University, Japan email: miurah@nsc.nagoya-cu.ac.jp ```
 **Related publication** ``` Miura, H., Numerical model for the
 solidification of a chondrule melt. Icarus 425 (2025) 116317
 https://doi.org/10.1016/j.icarus.2024.116317 ``` ## DATA STRUCTURE Unzip
 `datafile.zip` to find four directories containing visualization scripts
 (Python files) and data files, and one directory containing the
 unstructured triangular grid data, as shown below (files not shown): ```
 datafile.zip ├── Fig_3_4 ├── Fig_S1 ├── Fig_S2 ├── Fig_S3 └── meshdata ```
 ## DESCRIPTION OF DIRECTORIES AND FILES ### meshdata/ This directory
 contains the following three files related to the unstructured triangular
 grid for numerical calculations. ``` meshdata/ ├── FVM.msh ├── Tri.msh └──
 Th0.msh ``` The unstructured triangular grid consists of 4,669,147
 triangular elements and 2,337,088 nodes. The triangular elements are
 labeled with i, and the nodes are labeled with j. Each file contains the
 following information: 1. A `FVM.msh` file consists of two columns and
 4,669,147 rows; the i-th row indicates the coordinates of the i-th
 triangular element as follows: * **Column 1:** x-coordinate of the center
 of gravity of the triangular element * **Column 2:** y-coordinate of the
 center of gravity of the triangular element 2. A `Th0.msh` file consists
 of two columns and 2,337,088 rows; the j-th row indicates the coordinate
 of the j-th node as follows: * **Column 1:** x-coordinate of the node *
 **Column 2:** y-coordinate of the node 3. A `Tri.msh` file consists of
 three columns and 4,669,147 rows; the i-th row indicates the label of the
 three nodes that consist of the i-th triangular element as follows: *
 **Column 1:** label of 1st node * **Column 2:** label of 2nd node *
 **Column 3:** label of 3rd node ### Fig\_3\_4/ This directory contains
 Python scripts and numerical data for drawing the numerical simulation
 results of olivine crystal growth in a chondrule melt. The files included
 are as follows: ``` Fig_3_4/ ├── plot_Fig3ABCDEF.py ├── plot_Fig3G.py ├──
 plot_Fig4.py ├── 00001 ├── 00010 ├── 00025 ├── 00034 ├── 00044 ├── 00085
 └── TIMESTAMP_cp ``` 1. Files with 5-digit numerical names are numerical
 simulation data. The files `00001`, `00010`, `00025`, `00034`, `00044`,
 and `00085` correspond to the following elapsed times: t = 0.32343E-02 s,
 0.32378E-01 s, 0.81095E-01 s, 0.11041E+00 s, 0.14306E+00 s, and
 0.27777E+00 s, respectively. Each file consists of three columns and
 4,669,147 rows; the i-th row indicates the physical quantities of the i-th
 triangular element as follows: * **Column 1:** phase value (ϕ) * **Column
 2:** mole fraction of FeO (c1) * **Column 3:** mole fraction of SiO2 (c2)
 2. A `TIMESTAMP_cp` file shows the changes in physical quantities at each
 time step of the numerical calculation as follows: * **Column 1:** time
 step * **Column 2:** 5-digit number of the simulation data file
 corresponding to that time step (1 =&gt; `00001`, 10 =&gt; `00010`, and so
 forth) * **Column 3:** elapsed time corresponding to that time step in
 seconds * **Column 4:** temperature in Kelvin 3. A `plot_Fig3ABCDEF.py`
 file is a Python script to generate six snapshots showing the temporal
 evolution of the spatial distribution of phase (ϕ) and mole fraction of
 SiO2 (c2). Run the command `python plot_Fig3ABCDEF.py` on a computer with
 Python installed. Refer to the script header for the required modules.
 This script loads the following files: * `00001` * `00010` * `00025` *
 `00034` * `00044` * `00085` * `TIMESTAMP_cp` * `../meshdata/FVM.msh` *
 `../meshdata/Th0.msh` * `../meshdata/Tri.msh` 4. A `plot_Fig3G.py` file is
 a Python script to generate an enlarged image of a snapshot showing the
 spatial distribution of phase (ϕ) and mole fraction of SiO2 (c2). Run the
 command `python plot_Fig3G.py` on a computer with Python installed. Refer
 to the script header for the required modules. This script loads the
 following files: * `00034` * `TIMESTAMP_cp` * `../meshdata/FVM.msh` *
 `../meshdata/Th0.msh` * `../meshdata/Tri.msh` 5. A `plot_Fig4.py` file is
 a Python script to generate a snapshot showing the spatial distribution of
 phase (ϕ) and mole fraction of FeO (c1). Run the command `python
 plot_Fig4.py` on a computer with Python installed. Refer to the script
 header for the required modules. This script loads the following files: *
 `00085` * `TIMESTAMP_cp` * `../meshdata/FVM.msh` * `../meshdata/Th0.msh` *
 `../meshdata/Tri.msh` ### Fig\_S1/ This directory contains Python scripts
 and numerical data for drawing the temporal evolution of composition
 distributions within a chondrule melt undergoing evaporation, under
 various evaporation conditions. The files included are as follows: ```
 Fig_S1/ ├── L0.1_t10D-0.txt ├── L0.1_t10D-1.txt ├── L0.1_t10D-2.txt ├──
 L0.1_t10D-3.txt ├── L1_t10D-0.txt ├── L1_t10D-1.txt ├── L1_t10D-2.txt ├──
 L1_t10D-3.txt ├── L10_t10D-0.txt ├── L10_t10D-1.txt ├── L10_t10D-2.txt ├──
 L10_t10D-3.txt ├── plot_FigS1A.py ├── plot_FigS1B.py └── plot_FigS1C.py
 ``` 1. The 12 text files are the output results of the analytical solution
 of the concentration distribution. Different files correspond to the
 output results for different Peclet numbers L and elapsed times t as
 follows: `L0.1`, `L1`, and `L10` means L = 0.1, 1, and 10, respectively,
 and `t10D-0`, `t10D-1`, `t10D-2`, and `t10D-3` means t = 1, 10^{-1},
 10^{-1}, 10^{-1}, respectively. Each file consists of two columns as
 follows: * **Column 1:** distance from the droplet center r/a * **Column
 2:** concentration C/C0 2. A `plot_FigS1A.py` file is a Python script to
 generate a graph for the case of L = 10. Run the command `python
 plot_FigS1A.py` on a computer with Python installed. Refer to the script
 header for the required modules. This script loads the following files: *
 `L10_t10D-0.txt` * `L10_t10D-1.txt` * `L10_t10D-2.txt` * `L10_t10D-3.txt`
 3. A `plot_FigS1B.py` file is a Python script to generate a graph for the
 case of L = 1. Run the command `python plot_FigS1B.py` on a computer with
 Python installed. Refer to the script header for the required modules.
 This script loads the following files: * `L1_t10D-0.txt` * `L1_t10D-1.txt`
 * `L1_t10D-2.txt` * `L1_t10D-3.txt` 4. A `plot_FigS1C.py` file is a Python
 script to generate a graph for the case of L = 0.1. Run the command
 `python plot_FigS1C.py` on a computer with Python installed. Refer to the
 script header for the required modules. This script loads the following
 files: * `L0.1_t10D-0.txt` * `L0.1_t10D-1.txt` * `L0.1_t10D-2.txt` *
 `L0.1_t10D-3.txt` ### Fig\_S2/ This directory contains a Python script and
 numerical data for drawing the composition distributions of FeO and SiO2
 within the chondrule melt at the moment of seed-crystal introduction. The
 files included are as follows: ``` Fig_S2/ ├── data_FeO.txt ├──
 data_SiO2.txt └── plot_FigS2.py ``` 1. The two text files are the output
 results of the analytical solution of the concentration distribution.
 Files `data_FeO.txt` and `data_SiO2.txt` correspond to the output results
 for components FeO and SiO2, respectively. Each file consists of two
 columns as follows: * **Column 1:** distance from the droplet center r/a *
 **Column 2:** concentration C/C0 2. A `plot_FigS2.py` file is a Python
 script to generate the graph. Run the command `python plot_FigS2.py` on a
 computer with Python installed. Refer to the script header for the
 required modules. This script loads the following files: * `data_FeO.txt`
 * `data_SiO2.txt` ### Fig\_S3 This directory contains a Python script and
 numerical data for drawing the numerical simulation results of olivine
 crystal growth in a chondrule melt, but without considering anisotropy
 reduction in the evaporation layer. The files included are as follows: ```
 Fig_S3/ ├── plot_FigS3ABCDEF.py ├── 00001 ├── 00010 ├── 00025 ├── 00034
 ├── 00044 ├── 00085 └── TIMESTAMP_cp ``` 1. Files with 5-digit numerical
 names are numerical simulation data. The files `00001`, `00010`, `00025`,
 `00034`, `00044`, and `00085` correspond to the following elapsed times: t
 = 0.32343E-02 s, 0.32378E-01 s, 0.81095E-01 s, 0.11041E+00 s, 0.14306E+00
 s, and 0.27777E+00 s, respectively. Each file consists of three columns
 and 4,669,147 rows; the i-th row indicates the physical quantities of the
 i-th triangular element as follows: * **Column 1:** phase value (ϕ) *
 **Column 2:** mole fraction of FeO (c1) * **Column 3:** mole fraction of
 SiO2 (c2) 2. A `TIMESTAMP_cp` file shows the changes in physical
 quantities at each time step of the numerical calculation as follows: *
 **Column 1:** time step * **Column 2:** 5-digit number of the simulation
 data file corresponding to that time step (1 =&gt; `00001`, 10 =&gt;
 `00010`, and so forth) * **Column 3:** elapsed time corresponding to that
 time step in seconds * **Column 4:** temperature in Kelvin 3. A
 `plot_FigS3ABCDEF.py` file is a Python script to generate six snapshots
 showing the temporal evolution of the spatial distribution of phase (ϕ)
 and mole fraction of SiO2 (c2). Run the command `python
 plot_FigS3ABCDEF.py` on a computer with Python installed. Refer to the
 script header for the required modules. This script loads the following
 files: * `00001` * `00010` * `00025` * `00034` * `00044` * `00085` *
 `TIMESTAMP_cp` * `../meshdata/FVM.msh` * `../meshdata/Th0.msh` *
 `../meshdata/Tri.msh`