| Summary: | Abstract: Located at 78ºN, the island of Spitsbergen is covered by small glacal lakes. Linnévatent and Kongressvanet are two such lakes and are separated by about five kilometers along the western coast. These lakes have been part of an ongoing study to better understand the present and past climate changes. Chronology for cores recovered from these lakes is especially hard to establish, due to large amounts of detrial coal as well as the depletion of 14 C due to carbonate dissolution make 14 C-dating methods unreliable. During the summer of 2008 three cores were recovered from Linnévatnet with lengths of 32cm, 35cm and 65cm, near mooring sites D (core L08D), F (core L08F) and G (core L08G) respectively. In addition, one core (K08) from Kongressvatnet had a length of 67cm was collected. These were analyzed for paleomagnetic data finding that the K08 core gave a corrupted record, most likely due to the presence of gregite as shown by the environmental records. The Linnevatnet cores gave reliable records, with the longer record (L08G) having a sudden drop in declination at 33cm. This drop was the basis of the two age models. Age Model I based on the record given and dates the core to be 3500 years old. Age Model II involves a rotation of the declination data an dates the core to be ~350 years old. Based on grain size changes indicated by the environmental magnetic data as well as varve analysis of a similar core Age Model II is determined to be more valid, dating L08G to ~350 years BP. In addition L08D and L08F did not show enough variation to be compared to longer timescale, thus were only dated using Age Model II; giving ages of ~140 years BP for both cores.
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