This codebook.txt file was generated on 20230925 by Rebecca M. Hahn ------------------- GENERAL INFORMATION ------------------- 1. Title of Dataset: A Global Catalog of Deformed Volcanoes on Venus 2. Author Information Principal Investigator Contact Information Name: Rebecca M. Hahn Institution: Washington University in St. Louis Address: Department of Earth and Planetary Sciences, Washington University in St. Louis, St. Louis, MO, 63130 Email: h.rebeccahahn@wustl.edu ORCid: https://orcid.org/0000-0002-4425-434X Associate or Co-investigator Contact Information Name: Paul K. Byrne Institution: Washington University in St. Louis Address: Department of Earth and Planetary Sciences, Washington University in St. Louis, St. Louis, MO, 63130 Email: paul.byrne@wustl.edu ORCid: https://orcid.org/0000-0002-5644-7069 3. Date of data collection: Range 20220815-20230815 4. Geographic location of data collection: Earth, Environmental, and Planetary Sciences Department. Washington University in St. Louis, St. Louis, MO. 5. Information about funding sources that supported the collection of the data: N/A 6. Contextual description of the data: Gravitational instabilities can develop at volcanoes of any size, in any geologic setting and can lead to various types of volcano deformation, ranging from small-scale landslides on the flanks of the edifice, to large, deep-seated sector collapses. As volcanoes grow, they impose an increasing load on the underlying basement and lithosphere resulting in styles of gravitational deformation wherein the edifice sags under its own weight or spreads outward. In this study, we utilize our previously developed global catalog of volcanoes on Venus (Hahn & Byrne, 2023), to analyze a subset of edifices that appear to have undergone gravitational deformation. We identify 162 volcanoes displaying morphological evidence of gravitational deformation, and classify them into four main categories based on associated deformational structures: landsliding, sector collapse, sagging, and spreading. Through structural mapping and spatial analysis, coupled with comparative studies, we aim to quantify the various types and potential drivers of volcano gravitational collapse on Venus, shedding light on the processes of volcano evolution and collapse on the second planet. Any comments or questions can be referred to Rebecca M. Hahn at h.rebeccahahn@wustl.edu -------------------------- SHARING/ACCESS INFORMATION -------------------------- 1. Licenses/restrictions placed on the data: Public domain 2. Links to publications that cite or use the data: TBD (will update when paper is published) 3. Links to other publicly accessible locations of the data: TBD (will update when paper is published) 4. Links/relationships to ancillary data sets: A. A Global Catalog of Volcanoes and Shield Fields on Venus [version 2] We recommend using Version 2 of this dataset for analysis. We used our previously published global catalog of volcanoes on Venus, which includes a subset of deformed volcanoes as a basis for research. Version 2 Citation: Hahn, R., & Byrne, P. K. (2023). A Global Catalog of Volcanoes and Volcanic Fields on Venus (Version 2) [Data set]. Washington University in St. Louis. https://doi.org/10.7936/8XY0-X885 B. Ivanov and Head geologic map of Venus (2011) The dataset for coronae described by Ivanov and Head were used when calculating the distance from each deformed volcano to the nearest corona. Citation: Ivanov, M. A., & Head, J. W. (2011). Global geological map of Venus. Planetary and Space Science, 59(13), 1559-1600. https://doi.org/10.1016/j.pss.2011.07.008 5. Was data derived from another source?: Yes In our Global Catalog of Volcanoes on Venus (Hahn & Byrne, 2023), we document a unique subset of volcanoes that have undergone gravitational deformation (07_deformed.shp/07_deformed.csv). In this new dataset we have refined our selection of this subset of deformed volcanoes, and have expanded our morphological analysis. Our initial dataset of deformed volcanoes (07_deformed.shp/07_deformed.csv) contained 182 deformed volcanoes and included the latitude and longitude at the center of each volcano, and the area of the deformed volcano (which may have included debris aprons or other deformational features that extend away from the base of the edifice). The updated and refined version of this dataset contains 164 deformed volcanoes, and includes an additional 11 data fields (e.g., average deformed volcano width, and length). See data specific information for more details. 6. Recommended citation for the data: Hahn, Rebecca M. (2023). A A Global Catalog of Deformed Volcanoes on Venus. [dataset]. Washington University in St. Louis, WashU Research Data Repository. https://doi.org/10.7936/6rxs-103646. --------------------- DATA & FILE OVERVIEW --------------------- Data Structure Overview: The dataset is saved as two different file types: a shapefile, and a csv. This allows the users to spatially view the dataset by opening the shapefile in some type of GIS software (e.g., ESRI's ArcGIS, QGIS, GRASS GIS). Or if the user does not have access to GIS software, the data can also be viewed in tabular form by opening the csv file in programs such as Microsoft Excel or Google Sheets. Shapefiles: A shapefile is a geospatial vector data format that requires several mandatory files to open. In order to reduce the number of records associated with the "File List" below, only the .shp file will be listed, but each .shp dataset also includes the following: The shapefile in this dataset, includes the following mandatory files (DO NOT DELETE any of these files or it will not open!): 1. FILE.shp: shape format, the features geometry 2. FILE.shx: shape index format 3. FILE.dbf: attribute format for each shape Additional associated files that are not required to open the shapefile, but are recommended to keep with this dataset: 4. FILE.sbn: spatial index of features 5. FILE.prj: projection definition 1. File List A. Filename: Deformed_volcanoes_Venus.shp Short description: Shapefile containing polygon locations, morphological data, and spatial relationships for deformed volcanoes on Venus. Data is in Equirectangular Venus projection. B. Filename: Deformed_volcanoes_Venus.csv Short description: CSV table containing location data, morphological data, and spatial relationships for deformed volcanoes on Venus. 2. Relationship between files: This catalog includes one shapefile and one CSV file. The CSV file is tabular versions of the shapefile. These are available to users who may not have access to GIS software, but would still like to use the data. Shapefile data can also be read and visualized in MATLAB using the shaperead function (https://www.mathworks.com/help/map/ref/shaperead.html). 3. Additional related data collected that was not included in the current data package: See "A Global Catalog of Volcanoes and Shield Fields on Venus [version 2]" for a previous version of the deformed volcano dataset (07_deformed.shp/07_deformed.csv) Version 2 Citation: Hahn, R., & Byrne, P. K. (2023). A Global Catalog of Volcanoes and Volcanic Fields on Venus (Version 2) [Data set]. Washington University in St. Louis. https://doi.org/10.7936/8XY0-X885 -------------------------- METHODOLOGICAL INFORMATION -------------------------- 1. Description of methods used for collection/generation of data: We used ArcGIS Pro 3.0 software to analyze deformed volcanoes from our previously published global catalog of Venusian volcanic edifices (Hahn & Byrne, 2023). Detailed structural mapping was completed using the Magellan SAR (synthetic aperture radar) FMAP (full-resolution radar map) left- and right-look global mosaics at 75 meter-per-pixel resolution (Ford et al., 1993). For the equatorial region between 40° N and 40° S, mapping was completed in an Equirectangular projection. To preserve volcano geometry, datasets were projected as north- or south polar stereographic when mapping edifices at latitudes above 40° N and below 40° S, respectively. 2. Methods for processing the data: Morphological properties were determined for all deformed volcanoes. Properties include: A. Area (km²) B. Basal Length (km) C. Basal Width (km) D. Mean Basal Diameter (km) Spatial relationships were determined for all deformed volcanoes. Properties include: A. Distance to nearest coronae (km) B. Identification of tectonic structures within 50 km radius C. Identification of tectonic structures within 100 km radius D. Identification of tectonic structures within 200 km radius 3. Instrument- or software-specific information needed to interpret the data: Shapefiles can be read into a GIS software such as ESRI's ArcMap or ArcGIS Pro. Open source GIS software such as QGIS and GRASS GIS are also capable of reading shapefile data. CSV files can be open and read by most text editors such as Microsoft Word, and spreadsheet programs such as Microsoft Excel, or Google Sheets. 4. Standards and calibration information, if appropriate: N/A 5. Environmental/experimental conditions: N/A 6. Describe any quality-assurance procedures performed on the data: Data were reviewed and spot-checked by R.M. Hahn and P.K. Byrne to ensure consistency in mapping procedures and accuracy in data analysis methods. 7. People involved with sample collection, processing, analysis and/or submission: R.M. Hahn and P.K. Byrne ------------------------------------------------------- DATA-SPECIFIC INFORMATION FOR: A Note for ALL Datasets ------------------------------------------------------- 1. Variable List: FID/OID The shapefile contains an indexed feature identifier (FID). These are unique row identifiers that are not shared by any other feature within the dataset. Similarly, the corresponding csv file contains a unique object identifier (OID). The shapefile FID and csv OID correspond to the same records. ------------------------------------------------------------------------------------------ DATA-SPECIFIC INFORMATION FOR: Deformed_volcanoes_Venus.shp/ Deformed_volcanoes_Venus.csv ------------------------------------------------------------------------------------------ 1. Number of variables: 16 2. Number of cases/rows: 162 3. Missing data codes: N/A 4. Variable List A. FID/OID: feature identifier in .shp, object identifier in csv B. Shape*: geometry type (polygon) C. Lat_Center: latitude at center of volcano polygon (decimal degrees) D. Lon_Center: longitude at center of volcano polygon (decimal degrees) E. Area_Geo: basal geodesic area (km²) (this value may include debris aprons or other deformational features that extend away from the base of the edifice) F. Type: style of deformed volcano based on associated deformational structures landsliding = volcanoes with small scale landslides on their flanks. (associated structures: debris aprons, steep backscarps, and a stellate planform) sector collapse = volcanoes that have undergone a large, deep-seated collapse. (associated structures: debris avalanches, steep backscarps, and U-shaped collapse scars) landsliding, sector collapse = volcanoes with structures associated with both landsliding and sector collapse deformation spreading = volcanoes that have spread along a basal detachment due to their lateral weight gradient. (associated structures: folds and thrusts around edifice base, normal faults and leaf graben on flanks) sagging = volcanoes that have down-flexed the underlying basement and lithosphere from their weight (associated structures: flexural trough and bulge, peripheral graben on bulge, flank terraces) remnant = volcano that has undergone numerous collapse events indeterminate = volcano that is deformed in multiple styles or are otherwise difficult to classify with available data G. Diam_Width: length of the shortest basal axis (km) H. Diam_Length: length of the longest basal axis (km) I. Diam_Mean: mean basal geodesic area calculated from geometric mean of basal length and width (km) J. DebrisApron: Is a visible debris apron present? Y = debris apron is visible in Magellan SAR data N = no debris apron is visible in Magellan SAR data K. LV_Summit: Is this deformed volcano located at the summit of a large (>100 km in diameter) volcano? Y = deformed edifice is located at the summit of a large edifice N = deformed edifice is not located at the summit of a large edifice L. Corona_dist: geodesic distance (km) to nearest coronae using coronae shapefile from Ivanov and Head (2011) global geologic map of Venus M. within_50km: detailed description of tectonic structures (e.g., rift zones, ridge belts), impact craters, or other deformed volcanoes within a 50 km radius around the deformed volcano N. within_100km: detailed description of tectonic structures (e.g., rift zones, ridge belts), impact craters, or other deformed volcanoes within a 100 km radius around the deformed volcano O. within_200km: detailed description of tectonic structures (e.g., rift zones, ridge belts), impact craters, or other deformed volcanoes within a 200 km radius around the deformed volcano P. notes: additional descriptions, comments, or notes on the deformed volcano and any proximal structures