Link to USGS home page
USGS Home
Contact USGS
Search USGS
Coastal & Marine Geology InfoBank

USGS CMG InfoBank: Terranes

Skip navigational links
Search InfoBank
Home tab FACS tab Activities tab Atlas tab Geology School tab More tab More tab Geology School tabs
   
Dictionaries: The USGS and Science Education   USGS Fact Sheets   Topics   Keywords   Data Dictionary   Metadata Dictionary   Computer Terminology   Digital Formats
InfoBank Terms: Activity ID   activity overview   crew   formal metadata   lines   metadata   NGDC   port stops   project/theme   region   ship   stations   time   virtual globe   year  
Data Types: bathymetry   geodetic positioning   gravity   ground penetrating radar   imagery   LIDAR   magnetics   metering equipment   navigation   samples   seismic   definitions disclaimer  
Data Formats: ARC coverage   E00   FGDC metadata   gridded/image   imaging   material   scattered/swath   Shapefile   vector/polygon  
   
Comment: 15:08 - 16:02 (00:54)

Source: Annenberg/CPB Resources - Earth Revealed - 7. Mountain Building

Keywords: continent, seamount, "island arc", "Western North America", subduction, "Pacific Ocean", lithosphere, "exotic terrane", "suspect terrane", "accreted terrane", "fault zone", collision

Our transcription: Much of the landscape of Western North America is made up of continental fragments, seamounts and island arcs.

These land masses have attached to the continent during the subduction of Pacific Ocean lithosphere over the past 150 million years.

Such fragments are commonly described by geologists as "exotic, " "suspect, " or "accreted" terranes.

The term "terrane" refers to an area of rocks having continuous strata or structure and a distinctive composition.

The boundary between an accreted terrane and the main body of the continent may be marked by a fault zone or in places by a belt of oceanic rock, which was not subducted but caught in the squeeze between the colliding land masses.

Geology School Keywords

Skip footer navigational links


InfoBank   Menlo Park & Santa Cruz Centers   St. Petersburg Center   Woods Hole Center   Coastal and Marine Geology Program   Geologic Information   Ask-A-Geologist   USGS Disclaimer  

FirstGov button   Take Pride in America button