Plate boundaries can diverge, converge or slide past one another.
This Dynamic Earth is a historical agency synthesis; used here for boundary classification and kinematics.
USGS · Plate motionsThe seafloor keeps a record.: sources & model
Pull a ridge apart over millions of years. Read the age and magnetic pattern left behind, then compare spreading, sliding and subduction.
Scientific review · independent subject review pending
The source and model records are available for inspection. No external scientific reviewer has signed off yet.
plate-record-1 · content 1 · setup format 1What supports the explanation?
Paired magnetic patterns and independent dates helped support seafloor spreading.
Agency evidence account. Our stripes are hypothetical and are not copied measured profiles.
USGS · Magnetic stripes and clocksPaper strips can model spreading and subduction routing.
John C. Lahr’s original activity. Its simplified force/melting descriptions are not imported.
USGS · Paper spreading modelWhat this model assumes
- Generic symmetric ridge with prescribed constant half-rate, not a reconstruction of a specific ocean.
- Hypothetical irregular reversal schedules. Colors mean polarity in the record view and material in the boundary views.
- The narrow warm-colored ridge identifies a formation region. The underlying layers remain solid-model context; subducting rock is not shown instantly melting.
- Rate × time: A half-spreading rate of 3 cm/year moves one side 30 km in one million years. The matching pair is 60 km apart. The slider is a half-rate, not the total separation rate.
- Magnetic evidence is interpreted: Rock can preserve a magnetic record, while measured magnetic anomalies depend on geometry and magnetization. The colored strips are an ideal record, not a measured anomaly profile or a map of colored seafloor.
- The mantle is not a global lava ocean: Earth’s plates include oceanic and continental lithosphere. Much of the mantle is solid yet deforms over geological timescales. This kinematic model prescribes plate motion; it does not solve mantle flow, rock fracture, magma generation or earthquake prediction.
What has been checked
Analytical reference cases, conservation or transition invariants, finite drawing commands, bounded setup parsing, discovery and route integrity are checked automatically. These checks do not establish anatomical fidelity, learner outcomes or browser/device compatibility. Independent subject review, learner trials, comprehensive accessibility review and browser video encoding checks remain pending.
Each source supports the associated claim. Sources do not certify this implementation or its visuals.
About the cover illustration
The topic card uses an AI-generated editorial illustration. It introduces the subject; it is not a validated anatomical reference or a measured landscape. The experiment’s diagrams, readouts and assumptions explain the model separately.
Our review process