WebGeochem: DGGS Geochemical Sample Analysis Search Engine

Frequently-anticipated questions:

• What does this data set describe?
  1. How should this data set be cited?
  2. What geographic area does the data set cover?
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
  5. What is the general form of this data set?
  6. How does the data set represent geographic features?
  7. How does the data set describe geographic features?
• Who produced the data set?
  1. Who are the originators of the data set?
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
• Why was the data set created?
• How was the data set created?
  1. From what previous works were the data drawn?
  2. How were the data generated, processed, and modified?
  3. What similar or related data should the user be aware of?
• How reliable are the data; what problems remain in the data set?
  1. How well have the observations been checked?
  2. How accurate are the geographic locations?
  3. How accurate are the heights or depths?
  4. Where are the gaps in the data? What is missing?
  5. How consistent are the relationships among the data, including topology?
• How can someone get a copy of the data set?
  1. Are there legal restrictions on access or use of the data?
  2. Who distributes the data?
  3. What's the catalog number I need to order this data set?
  4. What legal disclaimers am I supposed to read?
  5. How can I download or order the data?
• Who wrote the metadata?

What does this data set describe?

1. How should this data set be cited?

   Freeman, L.K., Browne, C.B., Seitz, M.S., McCamish, John, and Guild, J.A., 2005, WebGeochem: DGGS Geochemical Sample Analysis Search Engine: None None, State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys, Fairbanks, AK, USA.

   Online Links:

   • <http://www.dggs.alaska.gov/webgeochem>

   Other_Citation_Details: Web application

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: 149.0000

   East_Bounding_Coordinate: -129.000

   North_Bounding_Coordinate: 71.0000

   South_Bounding_Coordinate: 51.0000

3. What does it look like?

4. Does the data set describe conditions during a particular time period?

   Beginning_Date: 1991

   Ending_Date: 18-Jun-2005

   Currentness_Reference: in development

5. What is the general form of this data set?

   Geospatial_Data_Presentation_Form: tabular digital data

6. How does the data set represent geographic features?
   1. How are geographic features stored in the data set?

      This is a Point data set.

   2. What coordinate system is used to represent geographic features?

      Horizontal positions are specified in geographic coordinates, that is, latitude and longitude. Latitudes are given to the nearest 0.0001. Longitudes are given to the nearest 0.0001. Latitude and longitude values are specified in Decimal degrees.

      The horizontal datum used is North American Datum of 1927.
      The ellipsoid used is Clarke 1866.
      The semi-major axis of the ellipsoid used is 6378206.4.
      The flattening of the ellipsoid used is 1/294.98.
      

7. How does the data set describe geographic features?

   Entity_and_Attribute_Overview:

   The WebGeochem search engine has three search pages: a main page, which has different fields dependent on search context, a quadrangle search page, and a place name search page. The search results consist of four linked tables that appear as pop-up windows: a main search results page that contains the analytical determinations of chemical constituents for the search result set of geologic samples, a linked table that contains descriptive and locality information for the sample. Items in the Sample field (a unique sample identifier present in Tables 1, 2, 3, 4, and in data tables defining spatial objects) are based on the following generic example:

   Entity_and_Attribute_Detail_Citation: None

   Main Page

   The main search page provides the main criteria for selecting the geologic sample types and geochemical analysis types that will be displayed in the results page; as well as providing either geographic criteria or preexisting data compilation lists by which to restrict the selected samples. All attributes within the main search page are contained in text boxes that appear based on the context of the current search. (Source: Alaska Division of Geological & Geophysical Surveys.)

   Sample Type

   The general class of material and sampling method that describes the samples to be included in the search results. (Source: Alaska Division of Geological & Geophysical Surveys)

   Text string from DGGS GERILA database DGGS_ANALYSIS.REF_SAMPLE_MATERIAL.sample_material

   Analysis Type

   A general classification of the chemical suite and methods used by the laboratory; this classification is arbitrary, but based on conventional usage and display of geochemical data. (Source: Alaska Division of Geological & Geophysical Surveys)

   Text string from DGGS GERILA database DGGS_ANALYSIS.REF_GEOCHEM_ANALYSIS_TYPE.geochem_analysis_type

   Quadrangle Name

   The full name of the 1:250,000 series quadrangle selected by the user using the quadrangle search page. (Source: Alaska Division of Geological & Geophysical Surveys.)

   Text string from DGGS_PUBLICATIONS.REF_QUADRANGLE.quad_name

   Map Sheet

   A concatenated text consisting of the label used to identify of a USGS 15 minute-series (1:63,360 scale) or 7.5 minute-series (1:24,000 or 1:25,000 scale) map sheet within the selected quadrangle AND an integer indicating the number of samples within the bounding coordinates of the map sheet. Only those map sheets that have sample analyses are listed in the drop down list. (Source: Alaska Division of Geological & Geophysical Surveys)

   Formal codeset
   Codeset Name:	DGGS_ANALYSIS.REF_MAP_SHEET.map_sheet_designator
   Codeset Source:	Alaska Division of Geological & Geophysical Surveys GERILA database

   Area Place Name

   Initially the partial or full place name entered by the user and is used to generate the place name list page. The value is replaced by the place name selected by the user from the place name list page. (Source: Alaska Division of Geological & Geophysical Surveys)

   Text string from DGGS_PUBLICATIONS.REF_ALASKA_PLACE_NAMES.place_name

   Point Place Name

   Initially the partial or full place name entered by the user and is used to generate the place name list page. The value is replaced by the place name selected by the user from the place name list page. (Source: Alaska Division of Geological & Geophysical Surveys)

   Text string from DGGS_PUBLICATIONS.REF_ALASKA_PLACE_NAMES.place_name

   Search Distance

   The search distance is the is the number of latitude minutes north and south and longitude minutes east and west from the coordinates of the named place to search for samples. User entered value, defaults to 5. (Source: Alaska Division of Geological & Geophysical Surveys)

   Range of values
   Minimum:	1
   Maximum:	999
   Units:	minutes

   North Bounding Coordinate

   The user entered latitude, in decimal degrees (dd.mmmm), of the northwest (upper left) corner of the area to be searched. (Source: Alaska Division of Geological & Geophysical Surveys)

   Range of values
   Minimum:	51
   Maximum:	71
   Units:	Decimal degrees

   West Bounding Coordinate

   The user entered longitude in decimal degrees (-ddd.mmmm), of the northwest (upper left) corner of the area to be searched. (Source: Alaska Division of Geological & Geophysical Surveys)

   Range of values
   Minimum:	-180
   Maximum:	-129
   Units:	Decimal degrees

   Range of values
   Minimum:	149
   Maximum:	180

   South Bounding Coordinate

   The user entered latitude, in decimal degrees (dd.mmmm), of the southeast (lower right) corner of the area to be searched. (Source: Alaska Division of Geological & Geophysical Surveys)

   Range of values
   Minimum:	51
   Maximum:	71
   Units:	Decimal degrees

   East Bounding Coordinate

   The user entered longitude in decimal degrees (-ddd.mmmm), of the southeast (lower right) corner of the area to be searched. Enter negative number between -180 degrees and -129 degrees (west longitudes) or a positive number between 149 and 180 degrees (east longitudes), and greater than (east of) the West Bounding Coordinate. (Source: Alaska Division of Geological & Geophysical Surveys)

   Range of values
   Minimum:	-180
   Maximum:	-129
   Units:	Decimal degrees

   Range of values
   Minimum:	149
   Maximum:	180
   Units:	Decimal degrees

   Project Name

   A short descriptive name of the DGGS field projects which were responsible for publication of geochemical sample analyses; only those projects that have associated sample analyses that meet the user selected analysis and sample type criteria are listed. (Source: Alaska Division of Geological & Geophysical Surveys)

   Formal codeset
   Codeset Name:	DGGS_PROJECT.PROJECT.project_name
   Codeset Source:	Alaska Division of Geological & Geophysical Surveys GERILA database

   Publication Number

   A text string that should uniquely identify a DGGS publication, and consists of the series abbreviation and issue number, and sometimes the year. This list in the drop down list is confined to those publications that contain sample and analyses types that have already been selected. (Source: Alaska Division of Geological & Geophysical Surveys)

   Formal codeset
   Codeset Name:	DGGS_PUBLICATIONS.V_PUBLICATIONS.publication_number
   Codeset Source:	Alaska Division of Geological & Geophysical Surveys GERILA database

   Thematic Data Set

   A short descriptive name that identifies a thematic compilation of geochemical sample analyses (Source: Alaska Division of Geological & Geophysical Surveys)

   Formal codeset
   Codeset Name:	DGGS_ANALYSIS.THEMATIC_DATASET.thematic_dataset_name
   Codeset Source:	Alaska Division of Geological & Geophysical Surveys GERILA database

   Quadrangle Search Page

   The quadrangle search page contains a map image with links behind each 1:250,000 scale quadrangle outline, and a list of quadrangle names that have sample analyses meeting selected criteria. (Source: Alaska Division of Geological & Geophysical Surveys.)

   Quadrangle Name

   The full name of the 1:250,000 series quadrangles that have samples meeting the previous search criteria, and appended with the number of samples that meet the search criteria. (Source: Alaska Division of Geological & Geophysical Surveys.)

   Text string from DGGS GERILA database DGGS_PUBLICATIONS.REF_QUADRANGLE.quad_name

   Three character abbreviation

   A three letter abbreviation used by DNR and some other agencies as codes to identify USGS quadrangles (Source: Alaska Division of Geological & Geophysical Surveys.)

   Formal codeset
   Codeset Name:	DGGS_PUBLICATIONS.REF_QUADRANGLE.three_letter_abbreviation
   Codeset Source:	Alaska Division of Geological & Geophysical Surveys GERILA database

   Place Name List

   A list of named places that match the user input text on the main page, the list includes other information about the locality of the place to resolve name repetition. (Source: Alaska Division of Geological & Geophysical Surveys.)

   Place Name

   Names of places from formal lists of places names in Alaska, duplicate names distinguished on the basis of location and feature type (Source: Alaska Division of Geological & Geophysical Surveys)

   Text string from DGGS GERILA database DGGS_PUBLICATIONS.REF_ALASKA_PLACE_NAMES.place_name

   Quadrangle Name

   The full name of the 1:250,000 series quadrangle in which the place is located (Source: Alaska Division of Geological & Geophysical Surveys.)

   Text string from DGGS GERILA database DGGS_PUBLICATIONS.REF_QUADRANGLE.quad_name

   Map Sheet

   A text string used to identify of a USGS 15 minute-series (1:63,360 scale) or 7.5 minute-series (1:24,000 or 1:25,000 scale) map sheet cell within which the place name is located, centered or starts. (Source: Alaska Division of Geological & Geophysical Surveys)

   Formal codeset
   Codeset Name:	DGGS_ANALYSIS.REF_MAP_SHEET.map_sheet_designator
   Codeset Source:	Alaska Division of Geological & Geophysical Surveys GERILA database

   Latitude

   The latitude, in decimal degrees (dd.mmmm) of the named place. (Source: Alaska Division of Geological & Geophysical Surveys)

   Range of values
   Minimum:	51
   Maximum:	71
   Units:	Decimal degrees

   Longitude

   The longitude in decimal degrees of the named place. (Source: Alaska Division of Geological & Geophysical Surveys)

   Range of values
   Minimum:	-180
   Maximum:	-129
   Units:	Decimal degrees

   Range of values
   Minimum:	149
   Maximum:	180
   Units:	Decimal degrees

   Feature Type

   A classification of the of geographic feature assigned by the authority for the place name, generally this is from the USGS Geographic Place Names Location Service (Source: Alaska Division of Geological & Geophysical Surveys)

   Text string from DGGS GERILA database DGGS_ANALYSIS.REF_ALASKA_PLACE_NAMES.place_feature_type

   Sample Count

   A count of the samples that are within the Map Sheet cell of the named place. (Source: Alaska Division of Geological & Geophysical Surveys)

   Range of values
   Minimum:	1
   Maximum:	19000
   Units:	each

   Search Results

   A tabular display of geologic sample analyses search criteria specified in the main search page and described both in the table header and at the foot of the page. Each analysis of a sample is arrayed in a row, and the chemical compositions are arrayed in columns according to the analytical parameters. Depending on the data available that meet the search criteria the number of columns may vary determined by the number parameter sets that are represented in the search results. A parameter set are the conditions under which the concentration of a chemical constituent was determined. (Source: Alaska Division of Geological & Geophysical Surveys.)

   Sample Identifier

   The text/number string assigned by the collection geologist to identify the sample, it typically consists of the locality identifier, and other information that should assure a unique value. The sample number is an HTML link to open the Sample Documentation page. (Source: Alaska Division of Geological & Geophysical Surveys.)

   Formal codeset
   Codeset Name:	DGGS_ANALYSIS.GEOLOGICAL_SAMPLE.assigned_sample_label
   Codeset Source:	Alaska Division of Geological & Geophysical Surveys GERILA database

   Latitude

   The geographic coordinate, latitude, in decimal degrees (dd.mmmm) of the location where the sample was collected. (Source: Alaska Division of Geological & Geophysical Surveys)

   Range of values
   Minimum:	51
   Maximum:	71
   Units:	Decimal degrees

   Longitude

   The geographic coordinate, longitude, in decimal degrees (dd.mmmm) of the location where the sample was collected. (Source: Alaska Division of Geological & Geophysical Surveys)

   Range of values
   Minimum:	-180
   Maximum:	-129
   Units:	Decimal degrees

   Range of values
   Minimum:	149
   Maximum:	180
   Units:	Decimal degrees

   Analysis Reference

   The primary unique identifier of the analysis in the DGGS database. The analysis reference is an HTML link to open the Analysis Documentation page. (Source: Alaska Division of Geological & Geophysical Surveys.)

   Formal codeset
   Codeset Name:	DGGS_ANALYSIS.ANALYSIS.analysis_id
   Codeset Source:	Alaska Division of Geological & Geophysical Surveys GERILA database

   Citation

   A string that identifies the bibliographic reference in which the analyses were originally published, each values is an HTML link to the full bibliographic reference. (Source: Alaska Division of Geological & Geophysical Surveys.)

   Formal codeset
   Codeset Name:	DGGS_PUBLICATIONS.V_PUBLICATIONS.publication_number
   Codeset Source:	Alaska Division of Geological & Geophysical Surveys GERILA database

   parameter number, chemical constituent, units

   Each column is contains chemical concentration determinations of the chemical constituent and units specified in the column header. The set of chemical parameters used to determine the concentration is identified by the number at the head of the column. Each column heading is an HTML link to the Chemical Parameters documentation page. (Source: Alaska Division of Geological & Geophysical Surveys GERILA database)

   The valid range of values and the methods used to determine the values are documented in the Geochemical Parameters table, each record of that table is linked to the column at the head of the Search Results table.

   Sample Documentation

   A tabular display of the description and geologic classification of the sample and information about the locality from which the sample was collected. (Source: Alaska Division of Geological & Geophysical Surveys.)

   Sample Identifier

   The text/number string assigned by the collection geologist to identify the sample, it typically consists of the locality identifier, and other information that should assure a unique value. (Source: Alaska Division of Geological & Geophysical Surveys.)

   Formal codeset
   Codeset Name:	DGGS_ANALYSIS.GEOLOGICAL_SAMPLE.assigned_sample_label
   Codeset Source:	Alaska Division of Geological & Geophysical Surveys GERILA database

   Collector

   The name of the collecting geologist. (Source: Alaska Division of Geological & Geophysical Surveys GERILA database)

   Names are concatenated from the DGGS GERILA database DGGS_PROJECT.CONTACTS.first_name and .last name

   Collection Date

   The day or month or year that the sample was collected. (Source: Alaska Division of Geological & Geophysical Surveys GERILA database)

   The dates are displayed, if known, only to the accuracy to which they are known.

   Location

   A named place that the geologist used to describe the general vicinity from which the sample was collected. (Source: Alaska Division of Geological & Geophysical Surveys GERILA database)

   Either null (blank) or from DGGS GERILA database DGGS_ANALYSIS.REF_ALASKA_PLACE_NAMES.place_name

   Latitude

   The geographic coordinate, latitude, in decimal degrees (dd.mmmm) of the location where the sample was collected. (Source: Alaska Division of Geological & Geophysical Surveys)

   Range of values
   Minimum:	51
   Maximum:	71
   Units:	Decimal degrees

   Longitude

   The geographic coordinate, longitude, in decimal degrees (dd.mmmm) of the location where the sample was collected. (Source: Alaska Division of Geological & Geophysical Surveys)

   Range of values
   Minimum:	-180
   Maximum:	-129
   Units:	Decimal degrees

   Range of values
   Minimum:	149
   Maximum:	180
   Units:	Decimal degrees

   Estimated Position Error

   The estimated circle of confidence for the location as recorded by GPS receivers or otherwise estimated by the collector (Source: Alaska Division of Geological & Geophysical Surveys GERILA database)

   Either null (blank) or a numeric value and a distance measurement unit from DGGS.

   Geodetic Horizontal Datum

   The name of the geodetic datum used in determining the latitude and longitude of the sample location (Source: Alaska Division of Geological & Geophysical Surveys)

   Presently all values are the same "North American Datum of 1927".

   Material Description

   A text description of the rock or other earth material represented by the sample. (Source: Alaska Division of Geological & Geophysical Surveys)

   Free text written, sometimes in code or abbreviations by the collector from DGGS GERILA database DGGS_ANALYSIS.GEOLOGIC_SAMPLE.sample_description.

   Field Locality Identifier

   The text string that identifies the field locality (field station, measured section, or bore hole) from which the sample was collected (Source: Alaska Division of Geological & Geophysical Surveys)

   Free text usually in the format YYIINNN, where YY=two digit year of the field season the locality was established, II = Initials, or other text signifying the identify of the geologist, and NUNN a three digit sequential number for the field station.

   Measured Section/Borehole Interval

   A text string that describes the interval in a bore hole or measured section that specifically describes the location of the material that the sample represents (Source: Alaska Division of Geological & Geophysical Surveys GERILA database)

   Free text usually in the format of ANN. to ANN. units, representing a stratigraphic distance above the starting point of a measured section or distance from the collar of a bore hole.

   Analysis Documentation

   Information about the conditions of a set or batch of chemical concentration determinations on geologic samples in a report by a laboratory. (Source: Alaska Division of Geological & Geophysical Surveys GERILA database)

   Analysis Reference

   The primary unique identifier of the analysis in the DGGS database. The analysis reference is an HTML link to open the Analysis Documentation page. (Source: Alaska Division of Geological & Geophysical Surveys.)

   Formal codeset
   Codeset Name:	DGGS_ANALYSIS.ANALYSIS.analysis_id
   Codeset Source:	Alaska Division of Geological & Geophysical Surveys GERILA database

   Laboratory

   The name of the laboratory that generated and provided the chemical analyses (Source: Alaska Division of Geological & Geophysical Surveys GERILA database)

   Free text from DGGS GERILA database DGGS_PROJECT.ORGANIZATION.organization

   Analysis Date

   The day, month, and/or year that the analysis is known that the analysis was completed or reported by the laboratory (Source: Alaska Division of Geological & Geophysical Surveys GERILA database)

   Formatted as MM/DD/YYYY but only to the accuracy of the known date DGGS GERILA database DGGS_ANALYSIS.ANAYSIS.analysis_date

   Analysis Description

   A narrative description of the sample preparation and analysis methods used to obtain the chemical determinations reported in the analysis of the samples (Source: Alaska Division of Geological & Geophysical Surveys GERILA database)

   Formatted as MM/DD/YYYY but only to the accuracy of the known date DGGS GERILA database DGGS_ANALYSIS.ANAYSIS.analysis_date

   Analysis Identifier

   A text string identifier that the laboratory assigns to the analysis report (Source: Alaska Division of Geological & Geophysical Surveys GERILA database)

   Unformatted free text string from DGGS GERILA database DGGS_ANALYSIS.ANAYSIS.job_batch_number

   Publication Documentation

   Bibliographic reference information that describes the published source for a sample analysis. (Source: Alaska Division of Geological & Geophysical Surveys GERILA database)

   Citation

   A string that identifies the bibliographic reference in which the analyses were originally published, each values is an HTML link to where the publication is available. (Source: Alaska Division of Geological & Geophysical Surveys GERILA database)

   Formal codeset
   Codeset Name:	DGGS_PUBLICATIONS.V_PUBLICATIONS.publication_number
   Codeset Source:	Alaska Division of Geological & Geophysical Surveys GERILA database

   Bibliographic Reference

   A string that identifies the bibliographic reference in which the analyses were originally published, each values is an HTML link to where the publication is available. (Source: Alaska Division of Geological & Geophysical Surveys GERILA database)

   Formatted free text string conformation to Suggestions to Authors rules constructed from columns in DGGS GERILA database DGGS_PUBLICATIONS.V_PUBLICATIONS.publication_number view

   Geochemical Parameter Documentation

   The definition of the chemical concentration determination values arrayed by column in the Sample Analysis table (Source: Alaska Division of Geological & Geophysical Surveys GERILA database)

   Chemical Species

   The chemical formula of the element or compound whose concentration is determined in the column determination in the column (Source: Alaska Division of Geological & Geophysical Surveys GERILA database)

   Formal codeset
   Codeset Name:	DGGS_ANALYSIS.REF_CHEMICAL_SPECIES.chemical_species_abbreviation
   Codeset Source:	Alaska Division of Geological & Geophysical Surveys GERILA database

   Parameters Set ID

   The primary unique numeric identifier of a set of geochemical parameters, and is referenced by the number in the column header in the Search Results Table (Source: Alaska Division of Geological & Geophysical Surveys GERILA database)

   Formal codeset
   Codeset Name:	DGGS_ANALYSIS.GEOCHEMICAL_CONSTRAINTS.geochemical_constraints_id
   Codeset Source:	Alaska Division of Geological & Geophysical Surveys GERILA database

   Parameters Set ID

   The primary unique numeric identifier of a set of geochemical parameters, and is referenced by the number in the column header in the Search Results Table (Source: Alaska Division of Geological & Geophysical Surveys GERILA database)

   Formal codeset
   Codeset Name:	DGGS_ANALYSIS.GEOCHEMICAL_CONSTRAINTS.geochemical_constraints_id
   Codeset Source:	Alaska Division of Geological & Geophysical Surveys GERILA database

   Analysis Method

   A descriptive name of the instruments and techniques used to determine the chemical compositions. (Source: Alaska Division of Geological & Geophysical Surveys GERILA database)

   Free text string from DGGS GERILA database DGGS_ANALYSIS.REF_GEOCHEM_TECHNIQUE.geochem_technique_name

   Units

   The concentration proportion "units" of measurement (percent, parts per million, Parts per billion, troy ounces per ton) (Source: Alaska Division of Geological & Geophysical Surveys GERILA database)

   Formal codeset
   Codeset Name:	DGGS_PROJECT.REF_UNITS.units_abbrev
   Codeset Source:	Alaska Division of Geological & Geophysical Surveys GERILA database

   Digestion/Prep

   A brief description of the methods used to get the sample into a form into which the analysis method can obtain a determination (Source: Alaska Division of Geological & Geophysical Surveys GERILA database)

   Free text string from DGGS GERILA database DGGS_ANALYSIS.REF_GEOCHEM_DIGESTION.digestion_description

   Comments

   The full name/description of the chemical species and any special considerations associated with that chemical species. (Source: Alaska Division of Geological & Geophysical Surveys GERILA database)

   Free text string from DGGS GERILA database DGGS_ANALYSIS.REF_CHEMICAL_SPECIES.chemical_species_full_name

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • Freeman, L.K.
   • Browne, C.B.
   • Seitz, M.S.
   • McCamish, John
   • Guild, J.A.

2. Who also contributed to the data set?

   The WebGeochem search engine was developed as a component of the DGGS Geologic Database Project which was funded under contract with the U.S. Geological Survey, Western Region Mineral Section, Alaska Branch, Minerals Data and Information at Risk in Alaska (MDIRA) program. Initial dataset compilation and digital geochemical datasets.

3. To whom should users address questions about the data?

Why was the data set created?

The geochemical analyses are extracted from DGGS and other geologic publications in Alaska, and are loaded into the GERILA database to establish a centralized archive of digital data in a uniform, well documented, and stable database system. This compilation is provided to the public through WebGeochem to facilitate geologic research that will lead to natural resource development and to facilitate natural resource planning across the state. The USGS, Western Region Mineral Section, Alaska Branch, Minerals Data and Information at Risk in Alaska (MDIRA) program provided funding for the GERILA database and compilation of digital geochemical datasets.

How was the data set created?

1. From what previous works were the data drawn?

2. How were the data generated, processed, and modified?

   Date: 2005 (process 1 of 2)

   Original geochemical digital geochemical data files are retrieved from DGGS project files reformatted to and loaded into the database along with the citation index.

   Date: 2005 (process 2 of 2)

   Sample description and locality information is retrieved in digital form from project files or from digital versions of the publication each locality is verified against. These files are loaded into the database with a logical check to ensure that the sample localities does not duplicate any other pre-existing sample localities, and then matches the sample description to a sample analysis.

3. What similar or related data should the user be aware of?

How reliable are the data; what problems remain in the data set?

1. How well have the observations been checked?

   Geochemical analyses displayed in WebGeochem are from multiple sources, documentation of the methods and accuracy of the determinations can be viewed in the Geochemical parameter documentation table which is available by clicking on a column heading the in the search results table.

2. How accurate are the geographic locations?

   Prior to 1998 DGGS sample sites were hand drawn on 1:63,360 scale topographic maps; location coordinates were then digitized or scaled from the maps. By 1998 Global Positioning Systems (GPS) receivers were used to directly record coordinates for some sample sites. Accuracy of GPS locations were subject to Selective Availability, a random 100 meter error assigned to GPS signals by the U.S. Government, until May 2000. Estimated position errors are specified individually for some samples; if not specified for an individual sample then the location may have an uncertainty of 100 meters or more.

3. How accurate are the heights or depths?

4. Where are the gaps in the data? What is missing?

   The DGGS database system only contains a portion of the geochemical data presented in DGGS publications. Users can view an estimate of the completeness for the data available to the DGGS WebGeochem application by clicking on the Database Status link at the bottom of the search page.

5. How consistent are the relationships among the observations, including topology?

   The four documentation tables are related to the search results table by sample number, analysis reference number, geochemical column header number, and citation identifier. The uniqueness of these identifiers and referential integrity are enforced by the database system.

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?

Access_Constraints:

This Web-based search engine and the web based tables are only available directly from the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys web page listed in the Identification-Citation-Online_Linkage above.

Use_Constraints:

Any hard copies or published datasets utilizing these datasets shall clearly indicate their source. If the user has modified the data in any way, the user is obligated to describe the types of modifications the user has made. User specifically agrees not to misrepresent these datasets, nor to imply that changes made by the user were approved by the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys.

1. Who distributes the data set? (Distributor 1 of 1)
   State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys
   c/o Lawrence Freeman
   Geologist IV
   3354 College Road
   Fairbanks, AK 99709-3707
   USA
   

   907-451-5020 (voice)
   907-451-5050 (FAX)
   lawrence.freeman@alaska.gov
   

   Hours_of_Service: 8 am to 4:30 pm Monday through Friday, except State holidays

   Contact_Instructions:

   Please view our Web site (<http://www.dggs.alaska.gov/webgeochem>) for the latest available data. Please contact us using the e-mail address provided above when possible.

2. What's the catalog number I need to order this data set?

   WebGeochem: DGGS Geochemical Sample Analysis Search Engine

3. What legal disclaimers am I supposed to read?

   The State of Alaska makes no express or implied warranties (including warranties of merchantability and fitness) with respect to the character, function, or capabilities of the electronic services or products or their appropriateness for any user's purposes. In no event will the State of Alaska be liable for any incidental, indirect, special, consequential, or other damages suffered by the user or any other person or entity whether from the use of the electronic services or products, any failure thereof, or otherwise, and in no event will the State of Alaska's liability to the requester or anyone else exceed the fee paid for the electronic service or product.

4. How can I download or order the data?
   • Availability in digital form:

     Data format:	HTML/text
     Network links:	<http://www.dggs.alaska.gov/webgeochem>

   • Cost to order the data:

     The Webgeochem search engine service can be accessed free of charge

5. What hardware or software do I need in order to use the data set?

   The Webgeochem search engine is optimized for Netscape 7, IE 6 or above, internet browser options must have Java applets enabled, and the pop-up blockers must be disabled for this search engine to function properly.

Who wrote the metadata?

Dates:

Last modified: 12-May-2008
Last Reviewed: 12-May-2008
To be reviewed: 12-May-2010

Metadata author:

State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys
c/o Lawrence Freeman
Geologist IV, Database Project Manager
3354 College Road
Fairbanks, AK 99709-3707
USA

907-451-5020 (voice)
907-451-5050 (FAX)
dggspubs@alaska.gov

Hours_of_Service: 8 am to 5 pm, Monday through Friday, except State holidays.

Contact_Instructions:

Please contact us using the e-mail address given above whenever possible.

Metadata standard:

FGDC Content Standards for Digital Geospatial Metadata (FGDC-STD-001-1998)