Metadata: Identification_Information: Citation: Citation_Information: Originator: Arnell S. Forde Publication_Date: 20221018 Title: 2015-330-FA_trkln: Digital Chirp Subbottom Profile Trackline Data Collected During USGS Field Activity Number 2015-330-FA Offshore of Dauphin Island, Alabama, September 2015 Geospatial_Data_Presentation_Form: Vector Digital Dataset (Polyline) Larger_Work_Citation: Citation_Information: Originator: Arnell S. Forde Originator: James G. Flocks Originator: Stanley D. Locker Publication_Date: 20221018 Title: Archive of Chirp Subbottom Profile Data Collected in 2015 From Dauphin Island, Alabama Series_Information: Series_Name: U.S. Geological Survey data release Issue_Identification: doi:10.5066/P9YTIG6G Publication_Information: Publication_Place: St. Petersburg, Florida Publisher: U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center Online_Linkage: https://doi.org/10.5066/P9YTIG6G Description: Abstract: From September 16 through 23, 2015, the U.S. Geological Survey (USGS) conducted geophysical surveys to investigate the geologic controls on barrier island evolution and sediment transport offshore of Dauphin Island, Alabama. Geophysical data were collected as part of the Alabama Barrier Island Restoration Feasibility Study. This shapefile represents a line dataset of field activity number (FAN) 2015-330-FA chirp tracklines. Purpose: To aid in the registering of digital chirp seismic reflection data collected during USGS FAN 2015-330-FA. Supplemental_Information: Additional survey and data details are available from the USGS Coastal and Marine Geoscience Data System (CMGDS) at, https://cmgds.marine.usgs.gov/fan_info.php?fan=2015-330-FA and in the Field Activity Collection System (FACS) and geophysical logs, which are included in the download file, 2015-330-FA_logs.zip (Forde and others, 2022). Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20150916 Ending_Date: 20150923 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -88.328428 East_Bounding_Coordinate: -88.040933 North_Bounding_Coordinate: 30.247492 South_Bounding_Coordinate: 30.158725 Keywords: Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:c5f6a328-761a-4bb1-81a3-ca0409df40dd Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: geoscientificInformation Theme_Keyword: oceans Theme_Keyword: location Theme: Theme_Keyword_Thesaurus: USGS Thesaurus Theme_Keyword: sub-bottom profiling Theme_Keyword: marine geology Theme_Keyword: geology Theme_Keyword: coastal processes Theme_Keyword: navigational data Theme_Keyword: geospatial datasets Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: trackline Theme_Keyword: barrier island mapping Theme_Keyword: seismic reflection Theme_Keyword: 2015-330-FA Theme_Keyword: chirp Place: Place_Keyword_Thesaurus: Common Geographic Areas Place_Keyword: Little Dauphin Island Place_Keyword: Alabama Place_Keyword: Gulf of Mexico Access_Constraints: None Use_Constraints: The U.S. Geological Survey requests to be acknowledged as originator of the data in future products or derivative research. Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Arnell S. Forde Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: Mailing and physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: 727-502-8000 Contact_Electronic_Mail_Address: aforde@usgs.gov Data_Set_Credit: Data collection and processing were performed by Jim Flocks, Stan Locker (former employee), and Arnell Forde of the USGS St. Petersburg Coastal and Marine Science Center. Native_Data_Set_Environment: Environment as of Metadata Creation: Microsoft Windows 10 Version 6.2 (Build 9200); Environmental Systems Research Institute (Esri) ArcMap 10.7.1.11595; Seismic Unix (Release 44). Data_Quality_Information: Logical_Consistency_Report: This dataset is from one field activity with consistent instrument calibrations. Completeness_Report: A total of 118 seismic lines were collected during this field activity. Two test lines, 2015-330-FA.001 and 2015-330-FA.002, were collected in Mobile Bay on DOY 258. Lines 2015-330-FA, JD-260, and JD-264.003 were partial lines containing no usable data and line JD-264.010 was corrupted during acquisition; consequently, all of the preceding lines were excluded from this data release. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: As the subbottom profile data were acquired, the position of the vessel was continuously determined by an Applanix POS MV Wavemaster II inertial aided navigation system (IANS), which is accurate to within 0.5-2 meters (m). Positions from the POS MV were recorded and written to seismic trace headers every second (s). The approximately 19-m offset between the chirp and GPS antenna has not been accounted for in the comma-delimited American Standard Code for Information Interchange (ASCII) navigation files and trackline map. Lineage: Process_Step: Process_Description: Navigation files were extracted from the seismic trace headers using Seismic Unix release 44 software, processed with PROJ.5.1.0 software to generate Universal Transverse Mercator (UTM) coordinates from latitude and longitude coordinates (World Geodetic System of 1984, WGS84), and then saved as ASCII text files in comma-separated values (CSV) format. Process_Date: 20220311 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Arnell S. Forde Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: Mailing and physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: 727-502-8000 Contact_Electronic_Mail_Address: aforde@usgs.gov Process_Step: Process_Description: The reformatted, text files were imported into Esri ArcMap 10.7 software to produce a geographic representation of the subbottom profile tracklines collected within the survey area. The PointsToLine script (located in the ArcToolbox) was used to create a shapefile (.shp) in which individual chirp shotpoints were connected to form tracklines. Process_Date: 20220322 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Arnell S. Forde Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: Mailing and physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: 727-502-8000 Contact_Electronic_Mail_Address: aforde@usgs.gov Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Vector Point_and_Vector_Object_Information: SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: String Point_and_Vector_Object_Count: 113 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Geographic: Latitude_Resolution: 0.0197878895 Longitude_Resolution: 0.0227703311 Geographic_Coordinate_Units: Decimal degrees Geodetic_Model: Horizontal_Datum_Name: WGS_1984 Ellipsoid_Name: WGS_84 Semi-major_Axis: 6378137.0 Denominator_of_Flattening_Ratio: 298.257223563 Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: 2015-330-FA_trkln.shp Attribute Table Entity_Type_Definition: Table containing attribute information associated with the dataset. Entity_Type_Definition_Source: U.S. Geological Survey Attribute: Attribute_Label: FID Attribute_Definition: Internal feature number. Attribute_Definition_Source: Esri Attribute_Domain_Values: Unrepresentable_Domain: Sequential unique whole numbers that are automatically generated. Attribute: Attribute_Label: Shape Attribute_Definition: Feature geometry. Attribute_Definition_Source: Esri Attribute_Domain_Values: Unrepresentable_Domain: Coordinates defining the features. Attribute: Attribute_Label: Line Attribute_Definition: Trackline name Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Unrepresentable_Domain: The naming convention used for each subbottom line is as follows: xy_bp_mod, where 'x' is an alphanumeric identifier indicating a specific trackline (for example, JD-262 or JD-265b), 'y' is a number (such as, .001, .002, etc.) representing a new line if recording was prematurely terminated or reran for quality or acquisition problems, and 'env_bp' denotes that the seismic traces were output as an envelope and a bandpass filter was applied. Attribute: Attribute_Label: Image Attribute_Definition: Graphics Interchange Format (GIF) image name Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Unrepresentable_Domain: This attribute field provides the name of the subbottom profile image (.gif) that is associated with each trackline as a hyperlinked GIF; a folder containing all these .gif files, named "images", is included in 2015-330-FA_gis.zip. Overview_Description: Entity_and_Attribute_Overview: Navigation files are available as ASCII delimited text files in CSV format. The final navigation files are provided in 2015-330-FA_nav.zip (Forde and others, 2022) and represent the reprojected survey shotpoint navigation, 1,000-shot-interval locations, and start of line files. The entity and attribute information provided here describes the tabular data associated with the shapefile, 2015-330-FA_trkln.shp. Please review the detailed descriptions that are provided (the individual attribute descriptions) for information on the values that appear as fields/table entries of the dataset. Entity_and_Attribute_Detail_Citation: The entity and attribute information were generated by the individual and/or agency identified as the originator of the dataset. Please review the rest of the metadata record for additional details and information. Distribution_Information: Distributor: Contact_Information: Contact_Person_Primary: Contact_Person: Arnell S. Forde Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: Mailing and physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: (727) 502-8000 Contact_Electronic_Mail_Address: aforde@usgs.gov Distribution_Liability: This publication was prepared by an agency of the United States Government. Although these data were processed successfully on a computer system at the U.S. Geological Survey, no warranty expressed or implied is made regarding the display or utility of the data on any other system, nor shall the act of distribution imply any such warranty. The U.S. Geological Survey shall not be held liable for improper or incorrect use of the data described and (or) contained herein. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: Shapefile, MXD, KMZ, GIF Format_Information_Content: 2015-330-FA_gis.zip contains the survey navigation data represented geospatially using a Google Earth keyhole markup language zipped (KMZ), Esri ArcMmap document (MXD), shapefiles, and a folder of processed subbottom profile images (GIF, accessible via hyperlinks included in the MXD). This metadata record describes the trackline locations provided in, 2015-330-FA_trkln.shp, which is one of the three Esri shapefiles included in the geographic information system (GIS) data ZIP file. File_Decompression_Technique: Winzip or 7zip Transfer_Size: 113.1 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://coastal.er.usgs.gov/data-release/doi-P9YTIG6G/data/2015-330-FA_gis.zip Fees: None Technical_Prerequisites: This shapefile was created for use with Esri ArcGIS software. It may also be viewed with Esri public domain software Explorer for ArcGIS, GeoMapApp 3.6.14 (http://www.geomapapp.org, 2021), or other GIS software capable of importing the data. Metadata_Reference_Information: Metadata_Date: 20220912 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Arnell S. Forde Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: Mailing and physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: (727) 502-8000 Contact_Electronic_Mail_Address: aforde@usgs.gov Metadata_Standard_Name: Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998