What is the Rift Valley Found on Many Mid-Ocean Ridges?

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24. Atlantic Seafloor

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Nearshore
Shelf
Shelf Break
Slope
Rise
Abyssal Plain
Abyssal Hills
Seamount
Mid-Ocean Ridge
Rift Valley
Transform
Fracture Zone
25. Pacific Seafloor
Nearshore
Shelf-Slope
Hawaii
Japan Trench
26. Review Results

27. California Margin

A rift valley is an elongate valley running along the length of the mid-ocean ridge.

 

Image Courtesy of Bill Ryan and RIDGE MultiBeam Synthesis Project

Color Scale for Water Depths

Rift valleys lie along the axis of the many mid-ocean ridges, containing many active volcanoes that mark the region where the oceanic crust is formed by volcanic eruptions.

In the diagram at the left, notice how the rift valleys are connected by another valley extending from left to right across the image.  This feature is known as a transform fault, which is oriented at 90o (perpendicular) to the rift valleys and mid-ocean ridge.

Also note that there is another elongate sea floor depression, known as a fracture zone, extending away from the transform (and outside of the rift valleys).  We will examine transforms and fracture zones in our future discussions on plate tectonics. 

Let's take one last look at our seafloor profile across the Atlantic Ocean,
and make some general observations...write them on your worksheet
before moving onto the North Pacific Ocean

profile_natl_bathy_35N_final.gif (10147 bytes)

 

Entrance to Harbor

Opening to Lisbon Harbor

The opening to Lisbon Harbor!
Now that is a cool lighthouse!

Hello Lisbon Portugal!

Lisbon Harbor

We have arrived in the harbor in Lisbon, Portugal, marking
the end of our first oceanic transect.
You will now depart the R/V Langseth in Lisbon and fly home to San Jose.

Created By:
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Don Reed
Dept. of Geology
San Jose State University
©Copyright 2008
Last Updated on 
Sept. 15, 2008
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