The HDDS Explorer user interface provides the overall capability for users to interact with the HDDS Explorer components and services. The HDDS Explorer user interface (Figure 1) is composed of the following key elements:

• Standard USGS header/footer elements and HDDS Explorer menu bar
• Body

Figure 1 - HDDS Explorer User Interface

A.  Header/Footer Elements

The HDDS Explorer header/footer elements are based on the USGS Visual Identification Policy standard guidelines. The HDDS Explorer client is compliant with Section 508 Workforce Rehabilitation Act of 1973  web content guidelines.

1.  Header

The HDDS Explorer client header (Figure 2) is located at the top of the web page. The header is common across all web pages in HDDS Explorer.

Figure 2 - Header

Elements of the header include:

• USGS Logo (upper left corner) reflects the relevance of the Bureau's work in today's world and communicates USGS’s purpose to the public.
• USGS Links (upper right corner) reflect links to the USGS website, USGS contact information, and the USGS search tool.
• Title Bar is a standard bar describing the website; in this case, ‘HDDS Explorer’.

2.  HDDS Explorer Menu Bar

The HDDS Explorer menu bar (Figure 3) is directly below the header. The HDDS Explorer menu bar supplies a common starting point to access additional functionality, options, and preferences for the HDDS Explorer client via drop-down menus.

Figure 3 - HDDS Explorer Menu Bar

The items in the menu bar include:

• Home - Returns you to your original starting point within the application.
• System Message - Provides links and information regarding system status and upcoming events/changes.
• Login - Provides a link to the HDDS Explorer Login service.
• Register - Provides a link to the USGS Registration Service.
• RSS - RSS feeds allow you to receive updates when new data is ingested into the HDDS.
• Feedback - Provides a link to the feedback form.
• Help - Provides information about HDDS Explorer.

Additional menu bar items display when you register or log in (Figure 4).

Figure 4 - HDDS Explorer Menu Bar with additional items

Some of these additional features include:

• Save Criteria - Allows you to save your current search criteria for future searches.
• Load Favorite - Allows you to load/apply a saved search criteria.
• Manage Criteria - Allows you to modify previously saved search criteria.
• Item Basket - Allows you to view items selected for bulk down and/or web map service orders.
• User Name Pop Down - Provides links to Event Access, Profile, Settings, and Logout.

These options are described in further detail in the HDDS Explorer Profile section.

3.  Footer

The HDDS Explorer client footer (Figure 5) is located at the bottom of the web page. The footer is common across all web pages in HDDS Explorer.

Figure 5 - Footer

The common menu items in the footer include:

• Accessibility - Provides a link to the USGS Accessibility Policy (Section 508).  The USGS Accessibility Policy ensures that all electronic and information technology developed, procured, maintained, or used by the USGS is accessible to people with disabilities.
• FOIA - Provides a link to the U.S. Geological Survey Freedom of Information Act (FOIA) Electronic Reading Room. FOIA requests for a copy of USGS records can be made by any individual or public/private organization other than a Federal agency.
• Privacy - Provides a link to the USGS Privacy Policies. This information identifies USGS and the Department of Interior (DOI) privacy policies.
• Policies and Notices - Provides a link to the USGS Policies and Important Notices website. This information describes the principal policies and other important notices that govern information posted on USGS websites.
• Google Maps API Disclaimer - Provides a link to the Google Maps API Disclaimer. This information outlines the Google Map Application Programming Interface (API) terms and conditions for using the Google Map service.

B.  Body

The body (Figure 6) includes the main HDDS Explorer capabilities and is composed of the Data Search Functions and the Google Map components.

Figure 6 - Body

1.  Search Criteria

The HDDS Explorer Data Search component is located on the left side of the HDDS Explorer body element. The Data Search components are divided among tabs in the search application to move through each portion of the process. The search process is divided into four main areas:

• Events Tab - Provides the interface for selecting the events to be searched.
• Search Criteria Tab - Provides the interface for entering basic search criteria of location and date.
• Additional Criteria Tab - Provides an interface for entering additional search criteria specific to the selected events.
• Results Tab - Initiates the search and provides the interface for displaying a textual and graphical view of the query results. Provides options for downloading data, exporting metadata, and ordering Web Map Service products.

Additional details on the Data Search component are provided in the Events Tab, Search Criteria Tab, Additional Criteria Tab, and Results Tab sections

2.  Google Map Interface

The Google Map component is located on the right side of the HDDS Explorer body element. The Google Map application interface embeds Google Maps within the HDDS Explorer client. The Google Map is a useful tool for defining a search area, visualizing spatial coverage, and for verifying that results fall in the area of interest.

Before using the Google Map component, you should be familiar with the navigation and location features provided in the Google Map interface for HDDS Explorer. 

Figure 7 - Google Map Navigation Controls

Use the following controls to navigate the Google Map (Figure 7):

• Pan Control - Click the appropriate arrow on the Pan Control to move the view north, south, east or west.
• Street View - Click and drag the Street View icon  to navigate to the street-level view of the interested area.
• Zoom - Click the plus sign (+) to zoom in to the center of the map; click the minus sign (–) to zoom out.
• Zoom Slider - Drag the zoom slider up/down to zoom in or out incrementally.
• Pan - Click and drag the map to the desired location or view.
• Use Page Up, Page Down, Home, and End for faster scrolling up, down, left, and right, respectively.

The Google Map component provides the following custom location features (Figure 8) to aid in locating point of interest.

Figure 8 - Custom Location Features

Google Maps offers the following location features:

• Coordinates - Coordinate values update as you move the mouse on the map interface.
• Options
  • Auto-Center - Centers the map on the display.
• Overlays - Displays a grid based on the selection
  • Decimal - Overlays a decimal degree grid over the map interface. Click to turn on and off.
  • DMS - Overlays Degrees, Minutes, Seconds (DMS) grid over the map interface. Click to turn on and off.
• Map/Satellite - Toggles between the Map View and the Satellite View.
  • Map View - Displays a street map.
    • Terrain - Shows basic topographic features.
  • Satellite View - Displays satellite imagery.
    • Labels - Displays feature labels (borders, states, countries, cities, interstates, streets, etc.).