I analyzed a section of Alaskan Loess to determine whether the signal recieved from Rock Magnetic experiments was a climate signal or the result of other soil forming processes. in particular I was concerned with a part of the signal that was suspected to be the Younger dryas cold snap well known in the north atlantic. Magnetic susceptibility measurements from a site 50 miles from my own showed increased values in a part of the profile dated at around the younger dryas period. The same increased susceptibility was seen at my own site (at the same magnitude and relative thickness) but the dates for the section have not yet arrived. Multiple magnetic tests were run to see whether the section had undergone sever alteration of magnetic minerals or if any processes were taking place that altered the composition of the section after deposition. We found that section has a very homogeneous parent material undergoing maghematization (a process that does not distort the other climateological parameters)that seems to have a consistant grain size distribution throughout. This means that the increased susceptibility signals displayed a region of higher concentration of magnetic grains and hence a period of increased wind intensity. This is definatly a climate signal and with loess in alaska increased winds means colder weather.

If this can be supported with other data it could be huge. The debate as to the global extent of the Younger Dryas is still going on. This research also lends itself to understanding how loess is in displaying reliable climate signals from within the same region (we know that loess from China or Argentina must be interpreted differently than loess from Alaska, but we hope that at least loess in Alaska from one region and another can be looked at the same.)
 
 

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