Magnetic microscopy promises a leap in sensitivity and resolution

Twenty years ago, Kirschvink argued that many paleomagnetic studies were limited by the sensitivity of the magnetometer systems then in use [ Kirschvink , 1981].He showed that sedimentary rocks could preserve detrital remanent magnetizations at levels of 10 −14 to 10 −15 Am 2 , about 100—1000 times below the noise level of today's best superconducting (SQUID) rock magnetometers. If a more sensitive magnetometer could be built, it would dramatically expand the range and variety of rock types amenable to paleomagnetic analysis. Just such an instrument is now on the horizon: the low‐temperature superconductivity (LTS) SQUID Microscope.