NEPTUNE Canada

Seafloor Spreading (Grade 8)

Author: Taken from Michele Svoboda, Mill Creek Middle School

Learning Objective(s)

For students to understand and be able to demonstrate the mechanisms involved with seafloor spreading.

Introduction

Begin this class by introducing the concept of seafloor spreading and continental drift which was first proposed 91 years ago by Alfred Wegener (but was accepted globally only about 40 years ago!). Explain that before him it was thought that the continents had always been where they are now.

Materials

• Two shoeboxes with lids
  
• World map with plate boundaries
  
• Internet access

Activity

• This is a demonstration of the mechanism of seafloor spreading.
  
• Have two shoeboxes resting upside down on a table with the lids resting perpendicular across the boxes. Write on the two lids – oceanic lithosphere (and explain the meaning).
  
• As you pull apart the two shoebox lids explain how magma comes from the Earth’s interior to fill the gap.
  
• Explain the driving forces of the plates and demonstrate on a map the presence of plates globally.
• Direct students to the NEPTUNE website to show real-time pictures of this geological phenomena and what is occurring in real-time at spreading centres. The Endeavour Ridge is extensively covered with instruments so students can investigate the chemistry, temperature, marine life and geological features which appear here. Discuss how it is different than other areas of the plate.

Extension

• Have students write a paragraph explaining what it would be like to live at the Endeavour Ridge.

Assessment

• No assessment – demonstration only.
  
• Discussion may be credited, regarding contribution and valid, accurate scientific data.
  
• Extension – assess written language and scientific knowledge. Has the student discussed hydrothermal vents, earthquake activity, temperature, topography, marine life, pressure, lack of sunlight, chemistry, chemosynthesis and more.

Related Website

Tags

seafloor spreading, continental drift, Alfred Wegener, continents, oceanic lithosphere, magma, the Earth’s interior, geological phenomena, topography, lack of sunlight, chemosynthesis