describe the movement of plates at a transfrom boundary , and give some examples.
A transform boundary is also called a conservative boundary. Check this site.
http://scign.jpl.nasa.gov/learn/plate4.htm
The movement of plates at a transform boundary is characterized by the plates sliding past each other horizontally. Unlike other types of plate boundaries where the plates diverge or converge, at a transform boundary, the plates neither move apart nor collide. Instead, they slide horizontally in opposite directions, with the motion occurring mainly along a prominent fault line.
As the plates slide past each other, they can get stuck due to friction. As stress builds up, they eventually overcome the friction, causing a sudden release of energy in the form of an earthquake. Transform boundaries are therefore often associated with frequent seismic activity.
One well-known example of a transform boundary is the San Andreas Fault System in California, USA. It marks the boundary between the Pacific Plate and the North American Plate. Due to the lateral movement at this transform boundary, frequent earthquakes occur in this region.
Another example is the North Anatolian Fault in Turkey, where the Eurasian Plate and the Anatolian Plate are sliding past each other. This region has experienced significant earthquakes in the past, including the devastating earthquake in Izmit in 1999.
So, to summarize, at a transform boundary, plates slide horizontally past each other along a fault line, causing frequent earthquakes. The San Andreas Fault in California and the North Anatolian Fault in Turkey are examples of transform boundaries.