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Buckeye Quads Released


Buckeye Quads Released

Newly designed US Topo maps for Ohio, featuring the Public Land Survey System, are now available online for free download

caption is available below.
Figure showing available PLSS areas on the new Ohio US Topo map. Note: “US Topo maps are not legal documents. The PLSS information shown on these maps is for general reference purposes only, and should not be used to determine legal boundaries or land ownership. The Bureau of Land Management (BLM) is the authoritative source for PLSS information at the federal level, and the US Topo representation is derived from BLM GIS data files. The management of these data is not completely uniform throughout the country.” (Larger image)

The USGS, in cooperation with other Federal agencies, has posted new Ohio US Topo quadrangles (748 maps) which include partial Public Land Survey System (PLSS). Ohio is the first state east of the Mississippi River to have PLSS data added to US Topo maps, joining Wyoming and Colorado in the west.

“It is great to have these 748 updated US Topo maps for our state available online at no charge,” said Charley Hickman, the Geospatial Liaison for Ohio. “We appreciate the continuing improvements in this product, including the availability of PLSS township, range, and section information.” 

The PLSS is a way of subdividing and describing land in the United States. All lands in the public domain are subject to subdivision by this rectangular system of surveys, which is regulated by the U.S. Department of the Interior. Other selected states will begin getting PLSS map data during the next respective revision cycle.

The new design for US Topo maps improves readability of maps for online and printed use, while retaining the look and feel of the traditional USGS topo map. Map symbols are easy to read when the digital aerial photograph layer imagery is turned on. 

Other re-design enhancements and new features:

  • New shaded relief layer for enhanced view of the terrain
  • Military installation boundaries, post offices and cemeteries
  • New road classification
  • A slight screening (transparency) has been applied to some features to enhance visibility of multiple competing layers
  • New PDF legend attachment
  • Metadata formatted to support multiple browsers

US Topo maps are created from geographic datasets in The National Map, and deliver visible content such as high-resolution aerial photography, which was not available on older paper-based topographic maps. The new US Topo maps provide modern technical advantages that support wider and faster public distribution and on-screen geographic analysis tools for users.

The new digital topographic maps are PDF documents with geospatial extensions (GeoPDF®) image software format and may be viewed using Adobe Reader, available as a no-cost download.

These new quads replace the first edition US Topo maps for Ohio. The replaced maps will be added to the USGS Historical Topographic Map Collection and are also available for free download from The National Map and the USGS Map Locator & Downloader website

US Topo maps are updated every three years. The initial round of the 48 conterminous state coverage was completed in September of 2012.  Hawaii and Puerto Rico maps have recently been added. More than 400 new US Topo maps for Alaska have been added to the USGS Map Locator & Downloader, but will take several years to complete.

For more information, go to: http://nationalmap.gov/ustopo/

USGS Newsroom


More information

Parameter Value Description
Magnitude mb The magnitude for the event.
Longitude ° East Decimal degrees longitude. Negative values for western longitudes.
Latitude ° North Decimal degrees latitude. Negative values for southern latitudes.
Depth km Depth of the event in kilometers.
Place Textual description of named geographic region near to the event. This may be a city name, or a Flinn-Engdahl Region name.
Time 1970-01-01 00:00:00 Time when the event occurred. UTC/GMT
Updated 1970-01-01 00:00:00 Time when the event was most recently updated. UTC/GMT
Timezone offset Timezone offset from UTC in minutes at the event epicenter.
Felt The total number of felt reports
CDI The maximum reported intensity for the event.
MMI The maximum estimated instrumental intensity for the event.
Alert Level The alert level from the PAGER earthquake impact scale. Green, Yellow, Orange or Red.
Review Status Indicates whether the event has been reviewed by a human.
Tsunami This flag is set to "1" for large events in oceanic regions and "0" otherwise. The existence or value of this flag does not indicate if a tsunami actually did or will exist.
SIG A number describing how significant the event is. Larger numbers indicate a more significant event.
Network The ID of a data contributor. Identifies the network considered to be the preferred source of information for this event.
Sources A comma-separated list of network contributors.
Number of Stations Used The total number of Number of seismic stations which reported P- and S-arrival times for this earthquake.
Horizontal Distance Horizontal distance from the epicenter to the nearest station (in degrees).
Root Mean Square sec The root-mean-square (RMS) travel time residual, in sec, using all weights.
Azimuthal Gap The largest azimuthal gap between azimuthally adjacent stations (in degrees).
Magnitude Type The method or algorithm used to calculate the preferred magnitude for the event.
Event Type Type of seismic event.
Event ID Id of event.
Event Code An identifying code assigned by, and unique from, the corresponding source for the event.
Event IDS A comma-separated list of event ids that are associated to an event.

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