Earth has 7 major plate tectonic boundaries and 10 or so minor ones.

Closely examine the map below, which shows the 15 major tectonic plates. A map showing some of the world's major and minor tectonic plates. Just centimeters each year. The world is composed of major, minor, and micro tectonic plates.

Superimposed in red are the more than 400 National Park System sites. The crust of our planet is cracked into seven large and many other smaller slabs of rock called plates, averaging about 50 miles thick. As they move (only inches every year), and depending on the direction of that movement, they collide, forming deep ocean trenches, mountains, volcanoes, and generating earthquakes. Plates & Boundaries. A gallery of map illustrations showing the positions of tectonic plates in the geologic past. Letter codes are abbreviations for parks on Tectonic Settings pages and the Tectonic Settings—Master List on the Plate Tectonics & Our National Parks page. The 2006 U.S. Geological Survey map of tectonic plates show 21 of the major plates, as well as their movements and boundaries. Geologists studying the Earth use scientific observation and evidence to construct a picture of what the Earth looked like at different periods in the geologic past. But they’re never idle. Earth’s tectonic plate boundaries are unusual because they can consist of continent and ocean crust. Shaded relief map of the U.S. highlighting different tectonic settings. Convergent (colliding) boundaries are shown as a black line with teeth, divergent (spreading) boundaries as solid red lines, and transform (sliding alongside) boundaries as solid black lines. Like seams of a baseball, tectonic plate boundaries wrap around the Earth. The earth's continents are constantly moving due to the motions of the tectonic plates. Tectonic plates are gigantic segments or pieces of the Earth's crust and uppermost mantle that together constitute the Lithosphere. Tectonic Plates.

As you can see, some of the plates contain continents and others are mostly under the ocean.

Plate tectonics have deceptively slow movement.