Map Index: User's Guide

Please contact DGGS at dnr.dggs.webapps@alaska.gov with any feedback or questions.

Frequently Asked Questions (FAQs)

Searching Records in Map Index

Appendices

Frequently Asked Questions (FAQs)

What is the Geologic Map Index of Alaska?

Map Index is a web-based tool to discover published geologic maps covering the state of Alaska. The application contains a text- and map-based search interface to make information easily accessible. The application provides links to DGGS's comprehensive publications database, where users may view and download publications for free.

User instructions for searching are provided below. More information about the application and underlying data can be found in the metadata file.

What types of geologic data does Map Index contain?

Traditional geologic maps are available through Map Index, as well as geophysical, sample location, geologic hazards, and geologic resources maps. Some maps may be indexed under multiple themes. Publications that do not represent data in horizonal, 2- or 3-dimensional space or are text-only reports can be accessed through DGGS's comprehensive publications database.

Is Map Index a comprehensive database of Alaska geology-related maps?

The number of maps in Map Index will be continually updated (status), and will eventually include other government agency map publications. Search our publications database for additional geologic information.

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Searching Records in Map Index

Map Index search philosophy

Map Index may be queried by geographic area, specific text, or a combination of area and text. All maps have an associated spatial footprint, either as an outline surrounding the area that was mapped or as a rectangular outline representing the extent of geologic mapping. The map outlines are generalized and do not correspond exactly with the actual mapped area.

Map Index help

Geographic-based searches

An Area of Interest (AOI) search is available from the map interface. Click on the AOI icon (active icon is yellow) and click and drag your mouse to define your area of interest. Geographic searches will often return spatial objects outside of the AOI selected, because a given record may be associated with multiple spatial objects, and all spatial objects for a record are displayed on the map. Search results (bibliographic information for the maps that match your request) may be exported to a PDF file by clicking on [Export], then select [Export Current Page]. You may repeat your exact search at a later time by saving the URL and re-entering it into the browser's address bar. Clear all of your search parameters by clicking [Reset].

Narrowing searches with the Selection Tool

The Selection Tool allows you to select spatial objects on the map, whose related publications are then highlighted in the results list below the map window. You may also select a publication in the results list and see it highlighted in yellow on the map. First, conduct either an Area of Interest (AOI), text-based, or combined search. To use the tool, click on the icon (active icon is yellow) and then click on either an object on the map or a check box next to a record in the results list. To select multiple items, click and drag your mouse on the map to select with a box or hold down the shift key while you click another item. To deselect an item, hold down the shift key and click on the item to unhighlight it. Selected publications' bibliographic information may be exported to a PDF file by clicking on [Export], then select [Export Highlighted]. Clear your selection by clicking [Clear Selected]. Clear all of your search parameters by clicking [Reset].

Text-based searches: Basic Search Bar

The application is designed to provide results for broad and narrowly focused searches. The Basic Search Bar above the map allows for robust queries of multiple single terms, phrases, term modifiers, and Boolean operators. The default behavior of the basic search bar is to select records on a "best match" basis. For example, a search for...

volcanic hazards ash

...will return only records that contain all three terms, singly or as a phrase, within any of the fields searched. Below is a table of additional ways to narrow queries in the basic search bar. These searching techniques may also be combined and grouped.

Search Example(s) Results
Term(s) volcanic hazards Returns records where both terms volcanic and hazards are present
Phrase "volcanic hazards" Volcanic hazards constraints, in Updike, R.G., Engineering geology, technical feasibility study, Makushin geothermal power project, Unalaska, Alaska
On specific fields @title volcanic
@title "volcanic hazards"
Returns any records wheretitle contains the term volcanic;
Volcanic hazards constraints, in Updike...
Proximity "ash map"~10 Returns records with any field that contains ash and map within 10 words of each other;
Ash fall contour map of the 2009 eruption of Redoubt Volcano, Alaska
Strict order operator "<<" geology << permafrost << wetlands Returns records only if terms are exactly in the query order; Preliminary photointerpretive maps of the geology, geologic materials, permafrost, and wetlands classification of the Fairbanks B-6 Quadrangle, Alaska
Boolean AND operator geology AND geologic Default operator between terms; returns records where the terms or phrases are found anywhere in the fields being searched
Boolean OR operator geology OR geologic Returns records with either geology or geologic, or both terms
NOT or "-" geology NOT geologic
geology -geologic
Both examples return records that contain geology but not geologic

The basic search bar searches the following fields: "title", "author", "year", "publication_number", "quadrangle", "keyword", "agency", "url", and "bibliography". See Appendix A for definitions of the fields. Note that your exact search may be duplicated at a later time by saving the URL and re-entering it into the browser's address bar. Clear all of your search parameters by clicking [Reset].

Text-based searches: Searching with "More Options"

The More Options button opens a side panel with additional fields to restrict searches. These parameters are more restrictive in the number of fields they query, and can help narrow down a search considerably. A search conducted on one or more fields from the More Options section and (or) the basic search bar will only return records that match all of the parameters entered. For example, a search conducted on...

Basic search bar: volcano
Agency: DGGS
Scale: 1:500,000 to 1:25,000,000

...will only return small-scale maps (covering a large area) published by DGGS that concern volcanoes. Below is a list of the fields involved in the More Options section parameters. See the Appendix B1 for a list of More Options fields with selectable values.

More Options Parameters Fields searched on
Agency Publishing organization
Year(s) To search a single or range of years when the map was published, the From and To fields must both be entered. A year entered in only the From field acts as a Greater Than or Equal To search; for example, "1980" entered into the From field will return records with a Year of "1980" or later. Conversely, "1980" entered into the To field will return records with a Year of "1980" or earlier.
Quadrangle(s) Searches for maps associated with 1:250,000-scale USGS quadrangle names, "Alaska General", or "Alaska Statewide." More than one quadrangle may be selected. If more than one quadrangle is selected, the search will find publications covering any of the quadrangles named. For example, if both "Fairbanks" and "Anchorage" quadrangles are selected, some maps returned will only cover Fairbanks and some will only cover Anchorage. Type "Fairbanks AND Anchorage" into the Basic search bar to find only maps that cover both Fairbanks and Anchorage quadrangles.
Scale To search a single or range of map scales, the From and To fields must both be entered. A scale entered in only the From field acts as a Greater Than or Equal To search; for example, "1:24,000" entered into the From field will return records with a 1:24,000-scale or larger scale denominator, up to 1:25,000,000. Conversely, "1:24,000" entered into the To field will return records with a map scale of 1:24,000 or smaller scale denominator, down to 1:1.
Include Statewide maps? As an additional modifier for searching on map scale, maps flagged as covering all or most of Alaska are not automatically included in searches. Click on the check box to include these maps in the search.
Themes Search among a general list of keywords that describe the dataset or item. A search on multiple Themes will return all records with those themes. See Appendix B2 for the list of Themes from which to choose.

Note that your exact search may be duplicated at a later time by saving the URL and re-entering it into the browser's address bar. Clear all of your search parameters by clicking [Reset].

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Appendices

Appendix A: "Basic Search Bar" field definitions

List of the fields and their definitions queried in the basic search bar. Additional information on the fields and tables behind this application are available from the digital data download on the Map Index citation page.

Object Field Names Definition
agencyPublishing organization
authorLast name of individual(s) who made the map
bibliographyConcatenated information for use in a typical publication listing. Petrik, W.A., 1993, Aquifers and hydrology at Anchor Point, Alaska, 24 p., 1 sheet, scale 1:25,000.
keywordWords or phrases describing the dataset such as the subject of the dataset, geographic location, geologic unit, or geologic time period
publication_numberPublication series and identifying publication number, sometimes containing the year
quadrangleUSGS 1:250,000-scale quadrangles (DNR metadata)
titleTitle to identify the publication
urlDGGS unique numerical identifier for the publication, i.e., http://www.dggs.alaska.gov/pubs/id/17921 where "17921" is the identifier
yearYear of publication

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Appendix B1: "More Options" fields with selectable values

Delimited lists ascribed to other parameters not mentioned above

Parameter Delimited List of acceptable values
Agency Any Agency
DGGS
USGS
Quadrangles "Alaska General": Generalized maps showing less geologic details
"Alaska Statewide": Maps covering all or most of Alaska
USGS 1:250,000-scale quadrangles (DNR metadata)
Scale From: 1:1; 1:24,000; 1:63,360; 1:100,000; 1:250,000; 1:500,000; 1:3,500,000
To: 1:24,000; 1:63,360; 1:100,000; 1:250,000; 1:500,000; 1:3,500,000; 1:25,000,000

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Appendix B2: Themes

Delimited list ascribed to parameter Themes.

Major category Minor category
GeologyBedrock; Derivative; Engineering; Generalized; Glacial; Image Interpretation; Surficial
GeophysicsGravity; Magnetics; Radiometrics; Remote Sensing; Resistivity
HazardsCoastal and River; Earthquake; Glaciers; Groundwater; Permafrost and Periglacial; Radon; Slope Instability; Volcanoes
OtherGeochemistry; Geochronology; Paleontology
ResourcesCoal; Geothermal; Metals; Non-Metals; Petroleum; Water

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