ISOTOPIC ANOMALY IN PEAT NITROGEN IS A PROBABLE TRACE OF ACID RAINS CAUSED BY 1908 TUNGUSKA BOLIDE

ln peat sampled at the Tunguska Cosmic: Body (TCB) explosion area, the sharp increase of the N concentration (about three-fold) and the posi tive N topic anomaly (delta(15)N = +3.5 parts per thousand, see eqn) h ave for the first time been revealed. In contrast with the C and H eff ects observed earlier which were clearly limited to the epicentre area (Kolesnikov et al., 1997 in press), the same N effect has also been s hown in peat sampled near the Vanavara settlement, 65 km south of the explosion epicentre. A clear connection of the observed anomalies in p eat to the 1908 permafrost boundary, synchronism of the changes of del ta(15)N and the N concentration and also good agreement with data on t he K/T boundary deposits allow us to connect the observed effects to a cid rain fall-out after passage and an explosion of the TCB. (C) 1998 Elsevier Science Ltd. All rights reserved.