Final answer:
The New Madrid Fault likely originated from a transform boundary, akin to the present-day San Andreas Fault, where the North American Plate was subjected to horizontal shearing forces.
Step-by-step explanation:
The New Madrid Fault is an example of what is likely a former intraplate fault system in the central United States. The stress that formed the fault was due to forces acting on the North American Plate, suggesting that the fault originated due to plate movement. While the type of boundary originally responsible for the formation of the New Madrid Fault is not explicitly mentioned in the provided materials, the described scenario where the plate tried to move in opposite directions suggests a transform boundary.
This is similar to the modern San Andreas Fault, which is a well-known transform boundary where two plates slide past one another horizontally.
The San Andreas Fault exhibits significant movement of the Pacific plate relative to the North American plate, where Los Angeles and San Diego are being carried northward, highlighting this lateral motion characteristic of transform boundaries.