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How To Use the Earthquake Reference Collection (ERC) 

The Earthquake Reference Collection contains professional studies targeting many technical and scientific areas of interest. Locating the particular reference you are seeking, out of more than 500 articles in the ERC, can be daunting. The following suggested search terms may help in locating specific articles, or just browsing the collection.

A useful way to search and explore the ERC is to understand its major categories:


Searching for a type of map will often provide information quickly. Some of the types of maps available in the ERC:

Searching for the author of a map or study is effective. Entering the name of the map author Ogden Tweto (well-known, Colorado geologist and former head of the Rocky Mountain Region of the US Geological Survey) will yield many items of interest. Searching according to map organization is often highly effective; many of the maps are of quadrangles and zones.


Many of these studies were created by, or for, major organizations concerned with public welfare. Searching for their name or acronym will locate many key documents:

Seismic Data

The terminology of seismic sciences is another way to search. This works especially well when the term is directly related to your major area of interest.


Seismic studies are a major focus of geologic sciences. Using some of the key terms for the type of study being done will yield effective results:


The results of most studies of pre-historic earthquakes in Colorado are in the ERC:

Geography - Locations

Where something happens is vital to understanding and measuring seismic events and phenomena. Here are some examples of geographic place names and features you will find information about in this collection:

Geography - Features
Geography covers a lot of ground (pun intended), and results in naming conventions of many types. All of these feature names have seismic data associated with them:


Often an event is important enough to generate an entire body of analysis and investigation. Try some of these suggestions to determine what is available in the ERC:

Searches based on other data will work in this collection when it is specific to information about seismic events in the State of Colorado. Many of these general categories will yield results in the ERC:

  • Colorado county names (Example:  Larimer)
  • Colorado city names (Example:  Meeker)
  • Other geologic features (canyons, gulches, mountains, rivers, valleys.  Example:  Black Canyon)
  • Name of any USGS quadrangle (Example:  Basalt)
  • Other geologic time periods (Example: Neogene)
  • mountain passes (Example:  Tennessee)
The Colorado Geological Survey’s Earthquake Reference Collection is here for your use. We hope you enjoy your exploration of this archive.

 Colorado Geological Survey
Last Updated: 12/20/2012 2:31 PM 
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