sea floor spreading

As two tectonic plates slowly separate molten material rises up from within the mantle to fill the opening. Seafloor spreading was discovered by Harry Hess who used maps created by sonar readings of the ocean floor.

Sea Floor Spreading Lecture Sea Floor Lecture Oceanography

Magma is extruded and intruded along the median zone of ridges a process accompanied by the separation of the flanking lithospheric plates so that new ocean floor is being continually formed.

. Sea floor spreading initiated near the beginning of the Late Jurassic ca 160Ma and continued for some 2025 million years splitting the attenuated crust while the margin began to experience thermal subsidence. So 1 km 100000 cm or 10 5 cm. Their crystals are pulled into alignment by the Earths magnetic field just like a compass needle is. The seafloor moves and carries continents with it.

Ad Build your Career in Data Science Web Development Marketing More. The seafloor spreading hypothesis was proposed by the American geophysicist Harry H. 1 km 1000 m. How was Seafloor Spreading Discovered.

Seafloor spreading and other tectonic activity processes are the result of mantle convection. In sea-floor spreading the sea floor spreads apart along both sides of a mid-ocean ridge as new crust is added. Ad Over 27000 video lessons and other resources youre guaranteed to find what you need. The process of seafloor spreading created the seafloor of the oceans.

As magma starts to harden into rock iron-rich minerals solidify first. A bathometer is an instrument that measures the depth of the oceans and it was an. Seafloor spreading happens at the bottom of an ocean as tectonic plates move apart. Invest 2-3 Hours A Week Advance Your Career.

For the North Atlantic Ocean using the map in the lab Measure the distance between the center of the spreading center red and the border between dark yellow and light green 65 Ma point I measured 2 cm. For example in the Atlantic Ocean North America and South America moved away from Europe and Africa and the resulting crack was filled by mantle material which cooled and formed new lithosphere. Sea floor spreading can stop during the process but if it continues to the point that the continent is completely severed then a new ocean basin is created. 1 m 100 cm.

Which is the first step in the seafloor spreading. At ridges in the middle of oceans new oceanic crust is created. The older rock is close to 400 million years. Calculating Sea Floor Spreading.

The process continues today. Most basalt magmas contain abundant molten iron. In this way the rugged volcanic landscape of a mid-ocean ridge is created along the plate boundary. Seafloor Spreading is the usual process at work at divergent plate boundaries leading to the creation of new ocean floor.

Purchase this Seafloor Spreading activity at Teachers Pay Teachers for 150 cents. Convection current s carry heat from the lower. The rate of sea-floor spreading is more or less symmetrical about the ridge adding to the plates on either side at the. Seafloor spreading is a process that occurs at mid-ocean ridges where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge.

A long crack in the oceanic crust forms at a mid ocean ridge. Mantle convection is the slow churn ing motion of Earths mantle. This video goes over the process of sea floor spreading and the evidence that supports this theory. The continental drift hypothesis did not gain much traction because it did not provide a viable mechanism to explain how the continents could move around the planet until the development of the bathometer during World War 2.

He noticed long chains of underwater mountains with the rift valley at their centers. Lets explore another idea called seafloor spreading. Seafloor spreading is a geologic process in which tectonic plate slarge slabs of Earths lithosphere split apart from each other. In this section we are going to take Alfred Wegeners thoughts a little further.

Click here if you are a student at Snowflake Heber or Holbrook to access the SUSD5 Student Version of Seafloor Spreading assignment. As a result the ocean floors move like conveyor belts carrying the continents along with them. Sea-Floor Spreading Activity Introduction. The motivating force for seafloor spreading ridges is tectonic plate pull rather than magma pressure although there is typically significant magma activity at spreading ridges.

On the basis of Tharps efforts and other new discoveries about the deep-ocean floor Hess postulated that molten material from Earths mantle continuously wells up along the crests of the mid-ocean ridges that wind for nearly 80000 km 50000 miles through all the worlds oceans. The Sedimentary Basins of the United States and Canada Second Edition 2019. Learn how to define sea floor spreading discover how people learned about it then. Sea floor spreading occurs when the two sides of a mid-ocean ridge move apart leaving magma to fill the gap.

Flexible Online Learning at Your Own Pace. Sea Floor Spreading Earth Science - Post Module 2 Middle School Page 3 The youngest rock will always be closest to the ridge area and the oldest will be on the outside closest to the continents.

Seafloor Spreading Seafloor Spreading Plate Tectonics Science Process Skills