Identification_Information: Citation: Citation_Information: Originator: U.S. Geological Survey Publication_Date: 20131129 Title: Bedrock Geologic and Structural Map Through the Western Candor Colles Region of Mars Edition: 1 Geospatial_Data_Presentation_Form: vector digital data Description: Abstract: Candor Colles are a population of low, conical hills along the southeast flank of Ceti Mensa, in west Candor Chasma, within the Valles Marineris system. The structure and geology of the layered deposits in the Candor Colles region corresponding to units Avfs, Avme and Hvl of (Witbeck and others, 1991) are reevaluated in this 1:18,000-scale map. The primary dataset used in mapping is a pair of stereo HiRISE observations PSP_001641_1735 and PSP_002063_1735. The 1 m/pixel orthorectified HiRISE images were most useful for identifying the mapped features (e.g., bedding, faults, unconformities), and the 0.25 m/pixel versions were used only to verify interpretations of meter-scale features such as bedforms and fault offsets that were initially made using the 1 m/pixel images. In this map, all units are allostratigraphic; that is, they are defined by unconformities at their upper and lower contacts. Allostratigraphy was selected because at HiRISE scale, bounding unconformities can be directly observed, are the most prominent stratigraphic divisions observed, and are mappable in a systematic way. While there are numerous unconformities in the mapped layered deposits, not all unconformities define unique geologic units. Instead, geologic units are identified primarily based on the most prominent regional unconformities observed within the map area and in adjacent areas. Secondarily, each geologic unit is further described based on characteristic surface expressions (albedo, erosional texture, bedforms). Each unit may contain numerous subordinate unconformities that do not define unit boundaries. The intent of this approach is to define broad units that are mappable at regional scales (i.e., these units could be sensibly included within a smaller-scale geologic map of west Candor Chasma in its entirety). This map is the first in a series of large-scale geologic maps in west Candor Chasma, and an important objective of this broader effort is to define units that can be correlated between maps. Further, only bedrock units were defined. Surficial materials such as eolian sand dunes were not mapped. Purpose: The objectives herein are to gather high-resolution structural measurements in order to 1) refine the previous unit boundaries in this area established by (Witbeck and others, 1991), 2) revise the local stratigraphy where necessary, 3) characterize bedforms to help constrain depositional processes, and 4) determine the styles and extent of deformation to better inform reconstructions of the local post-depositional geologic history. Reference: Witbeck, N.E., Tanaka, K.L., and Scott, D.H., 1991, Geologic map of the Valles Marineris region, Mars: U.S. Geological Survey, scale 1:2,000,000. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20130501 Ending_Date: 20131129 Currentness_Reference: Processing dates not dates for geologic map which would be (Noachian, Hesperian, Amazonian) Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -75.832909 East_Bounding_Coordinate: -75.702791 North_Bounding_Coordinate: -6.496682 South_Bounding_Coordinate: -6.857468 Keywords: Theme: Theme_Keyword_Thesaurus: NASA Science Glossary Theme_Keyword: Mars Theme_Keyword: Geology Theme_Keyword: Structure Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Categories Theme_Keyword: elevation Theme_Keyword: geoscientificInformation Theme_Keyword: imageryBaseMapsEarthCover Theme_Keyword: structure Place: Place_Keyword_Thesaurus: USGS/IAU Planetary Nomenclature Place_Keyword: Mars Place_Keyword: Valles Marineris Place_Keyword: Candor Chasma Place_Keyword: Candor Colles Access_Constraints: None Use_Constraints: None Point_of_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Chris Okubo Contact_Position: Geophysicist Contact_Address: Address_Type: physical Address: 2255 North Gemini Drive City: Flagstaff State_or_Province: AZ Postal_Code: 86001 Country: US Contact_Voice_Telephone: 520-626-0762 Contact_Electronic_Mail_Address: cokubo@usgs.gov Data_Set_Credit: Chris H. Okubo Native_Data_Set_Environment: Esri ArcGIS 10 Data_Quality_Information: Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: 0.25 m/pixel Quantitative_Horizontal_Positional_Accuracy_Assessment: Horizontal_Positional_Accuracy_Explanation: Horizontal accuracy is limited to the accuracy of the Mars Orbiter Laser Altimetry elevation model as described in Kirk and Others, 2008. Reference: Kirk, R.L., Howington-Kraus, A.E., Rosiek, M.R., and 16 others, 2008, Ultrahigh resolution topographic mapping of Mars with MRO HiRISE stereo images: Meter-scale slopes of candidate Phoenix landing sites: Journal of Geophysical Research, v. 113, no. E3, p. E00A24. Lineage: Source_Information: Source_Scale_Denominator: 18000 Type_of_Source_Media: hardDisk Source_Contribution: The primary dataset used in mapping is a pair of stereo HiRISE observations, PSP_001641_1735 and PSP_002063_1735. Both observations were acquired during late southern winter, with incidence angles near 55°. A DTM with 1-m post spacings is extracted from the red bandpasses (550-850 nm) of these two observations. Both images in turn are orthorectified to the DTM, output at 1 m/pixel and 0.25 m/pixel, and compressed using JPEG2000. Process_Step: Process_Description: The DTM production and image orthorectification follows the methodology outlined by (Kirk and others, 2008). Mapping was conducted exclusively within the areal extent of the DTM, thus the region of stereo overlap in HiRISE stereopair H1 effectively defines the map area. The 1 m/pixel orthorectified HiRISE images served as the mapping base. Reference: Kirk, R.L., Howington-Kraus, A.E., Rosiek, M.R., and 16 others, 2008, Ultrahigh resolution topographic mapping of Mars with MRO HiRISE stereo images: Meter-scale slopes of candidate Phoenix landing sites: Journal of Geophysical Research, v. 113, no. E3, p. E00A24. Process_Date: 20130304 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Chris Okubo Contact_Position: Geophysicist Contact_Address: Address_Type: physical Address: 2255 North Gemini Drive City: Flagstaff State_or_Province: AZ Postal_Code: 86001 Country: US Contact_Voice_Telephone: 520-626-0762 Contact_Electronic_Mail_Address: cokubo@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: GT-polygon composed of chains Point_and_Vector_Object_Count: 8 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: Entity point Point_and_Vector_Object_Count: 561 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: Entity point Point_and_Vector_Object_Count: 229 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: Entity point Point_and_Vector_Object_Count: 29 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: Entity point Point_and_Vector_Object_Count: 9 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: String Point_and_Vector_Object_Count: 366 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: String Point_and_Vector_Object_Count: 327 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: String Point_and_Vector_Object_Count: 17 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: String Point_and_Vector_Object_Count: 67 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: GT-polygon composed of chains Point_and_Vector_Object_Count: 3 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: String Point_and_Vector_Object_Count: 225 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: String Point_and_Vector_Object_Count: 1191 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: GT-polygon composed of chains Point_and_Vector_Object_Count: 24 SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: String Point_and_Vector_Object_Count: 1 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Map_Projection: Map_Projection_Name: WCandor - MTM clon-75clat0 Transverse_Mercator: Scale_Factor_at_Central_Meridian: 1.0 Longitude_of_Central_Meridian: -75.0 Latitude_of_Projection_Origin: 0.0 False_Easting: 0.0 False_Northing: 0.0 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: coordinate pair Coordinate_Representation: Abscissa_Resolution: 0.0001 Ordinate_Resolution: 0.0001 Planar_Distance_Units: meter Geodetic_Model: Horizontal_Datum_Name: D Mars 2000 Sphere Ellipsoid_Name: Mars 2000 Sphere IAU IAG Semi-major_Axis: 3396190.0 Denominator_of_Flattening_Ratio: 0.0 Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: Geologic Units Entity_Type_Definition: Layer representing geologic units Entity_Type_Definition_Source: Geologic symbol type in table and describe in this publication write up. Detailed_Description: Entity_Type: Entity_Type_Label: Faults Entity_Type_Definition: Layer representing faults Entity_Type_Definition_Source: Fault type in table and described in this publication write up. Detailed_Description: Entity_Type: Entity_Type_Label: Folds Entity_Type_Definition: Layer representing folds Entity_Type_Definition_Source: Fold type in table and described in this publication write up. Detailed_Description: Entity_Type: Entity_Type_Label: Contacts Unconformities Entity_Type_Definition: Layer representing unconformities Entity_Type_Definition_Source: for more about this layer see description in this publication write up. Detailed_Description: Entity_Type: Entity_Type_Label: Bedding Orientations Entity_Type_Definition: Layer representing bedding orientations Entity_Type_Definition_Source: Bedding angle stored in table. See description in this publication write up. Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geologic Survey Contact_Person: USGS Publications Contact_Address: Address_Type: physical Address: 12201 Sunrise Valley Drive City: Reston State_or_Province: VA Postal_Code: 20192 Country: US Contact_Voice_Telephone: 1-888-ASK-USGS Contact_Electronic_Mail_Address: http://pubs.er.usgs.gov/feedback Distribution_Liability: See access and use constraints information. Metadata_Reference_Information: Metadata_Date: 20131126 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Trent Hare Contact_Position: Cartographer Contact_Address: Address_Type: physical City: 2255 North Gemini Drive State_or_Province: AZ Postal_Code: 86001 Country: US Contact_Voice_Telephone: 928-556-7126 Contact_Electronic_Mail_Address: thare@usgs.gov Metadata_Standard_Name: FGDC Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Time_Convention: local time Metadata_Use_Constraints: None. Public domain. Please cite author(s). Metadata_Security_Information: Metadata_Security_Classification: Unclassified