Chlorine-36 evidence for the Mono Lake event in the Summit GRIP ice core

A distinct peak has been discovered in the Cl-36 data from the GRIP ice cor e between the Dansgaard Oeschger (D-O) events 6 and 7 at approximately 32 k yr BP. This peak can be attributed to a minimum of the geomagnetic dipole f ield associated with the Mono Lake event, Since the Cl-36 peak reflects a h igher production rate of all cosmogenic radionuclides, it has an impact on the C-14 dating of the last ice age. Furthermore, it provides an additional time marker similar to a peak found earlier corresponding to the Laschamp event at approximately 39 kyr BP. (C) 2000 Elsevier Science B,V, All rights reserved.