Please help me with my science project! Cape Ann Earthquake 1755?

Question

Please help me with this!

What fault caused the Cape Ann Earthquake in 1755 and what were the other scientific reasons it occured? Feel free to add any cool science facts that i could use! Thanks so much

Answer 1

The occurrence of earthquakes in the northeastern United States apparently violates the plate tectonic model. The past several decades of research on this topic, however, have demonstrated that it may be possible to explain the occurrence of earthquakes in the Northeast within the framework of plate tectonics. The challenge in figuring out why the Earth quakes in New England is that the earthquake process in plate interiors is more complex than at plate boundaries. Unlike the situation in California, there is no obvious relationship between earthquakes and geologically mapped faults in most intraplate areas.

With plate tectonics under their belt and a seemingly endless supply of research funds flowing in, a number of geologists and geophysicists in the mid-1970's turned their attention to a (presumably) straightforward problem: What causes intraplate earthquakes? These were heady times for seismologists, and some were quite confident that the problem would be easily resolved. Hypotheses abounded. With a minimum of data available, it sometimes seemed like there was more fanciful hypothesis-generating than hypothesis testing. Two well-known hypotheses to explain earthquakes in the Northeast were the supposed existence of a "Boston-Ottawa seismic zone" and the presumed activity of the Ramapo fault (an ancient geological fault in northern New Jersey and southeastern New York State). In spite of many such attempts to explain the cause of earthquakes in the Northeast, however, none of these specific hypotheses have fared very well in light of new data gathered in the 1980's and 1990's.

At the present time, a commonly accepted explanation for the cause of earthquakes in the Northeast is that "ancient zones of weakness" are being reactivated in the present-day stress field. In this model, preexisting faults and/or other geological features formed during ancient geological episodes persist in the intraplate crust, and, by way of analogy with plate boundary seismicity, earthquakes occur when the present-day stress is released along these zones of weakness. Using this model as a guide, much of the research on northeastern United States earthquakes has involved attempts to identify preexisting faults and other geological features that might be reactivated by the present-day stress field. While this concept of reactivation of old zones of weakness is commonly assumed to be valid, in reality the identification of individual active geologic features has proven to be quite difficult. Unlike the situation for many plate boundary earthquakes, it is not at all clear whether faults mapped at the earth's surface in the Northeast are the same faults along which the earthquakes are occurring.