| In palaeoclimatic and palaeoenvironmental history research on continents, lake sediment records, especially annually laminated (varved) lake sediments, are an important geological archives because one major benefit of varved sediments is that commonly provide the large variety of high resolution proxy data directly from the continents and the second is they are the possibility to establish precise incremental time scales in calendar year through varve counting if we can identify the characters and the components of the varves. With the increasing number of studies on high resolution lake sediment, it has become evident that a reliable and precise chronology is crucial to correlate these records in order to better understand the regional variability of environmental and climatic changes.In China, annually laminated sediments have been recognized at widespread geographic locations, however, only few laminated sediment records have been found and have better achievement. A group of several small maar lakes from Longgang Volcanic Field, NE China, preserve annually lamination and are high resolution geological archives because of special origin.In this paper, in order to reconstruct paleoclimatic and paleoenvironmental variety since the deglaciation on the bases of the study of varve from sediment core and multi-proxies (including, dry density, total organic carbon, total nitrogen et al.,)in Erlongwan maar lake NE China, the author acquire main results and conclusions as following:1. The Erlongwan maar lake, forced by the Northeast Asian monsoon, is a close crater lake which is shaped by the volcano eruption. Because it preserves fine entironment, continuous lake sediments and plenty archive on climate and environment, it is an important geological archive of palaeoclimatic and palaeoenvironmental information with up to seasonal resolution.2. Sediment (0-2 391 cm) from the Erlongwan maar lake, with fine annual lamination, have been demonstrated two main varve type, the biogenic varve ( top of the core: 0-632 cm)and the clastic varve ( below of the core:632-2 391 cm). Based on the algae type and its content, the types of the biogenic varve in sediments can be classified into dinocyst-biogenic varve which content of the dinocyst is more than 95 %(0-63 cm) and mixed (diatom and dinocyst)-biogenic varve( 214-632 cm).It is the first time in China that dinocyst and the dinocyst-biogenic varve are found in the fresh water. Whereas we don't still know about the formation of the dinocyst, components and microcharacter of the varve have already identified, which will offer a scientific method for further varve counting, assessment of error and varve thickness variety and so on.3. Combining vave counting with AMS 14C, 137Cs and 210Pb dating results, we established the high resolution chronology series since 14 000 a B.P., which is the most accurate late Quaternary geological mark so far in China and can link with historic records. 4. We test total organic carbon(TOC), total nitrogen(TN) and dry density(DD) of the sediments lake from the Erlongwan maar lake, which provide more sensitiveproxy for the climatic and environmental variety in this region. 5. On the base of the high resolution scale and proxy of the climate and environment, we reconstruct high resolution palaeoclimatic and palaeoenvironmental variety series since the last deglaciation. It shows 2 stages, 5 cycles segment and 19 climate events since 14 000 a B.P., as following: 1 13 730±374 - 13 571±362 a B.P. 2 13 570±362 - 12 598±349 a B.P. 3 12 597±349 - 11 485±316 a B.P. 4 11 484±316 - 11 243±302 a B.P. 5 11 242±302 - 10 140±281 a B.P. 6 10 139±281-9 474±269 a B.P. 7 9 473±269 - 9 059±251 a B.P. 8 9 058±251 - 8 450±236 a B.P. 9 8 449±236 - 8 120±227 a B.P. 10 8 119±227 - 7 798±205 a B.P. 11 7 797±205 - 4 972±182 a B.P. 12 4 971±182 - 4 096±157 a B.P. 13 4 095±157 - 3 782±142 a B.P. 14 3 781±142 3 400±136 a B.P. 15 3 399±136– 2 815±110 a B.P. 16 2 814±110– 1 658±68 a B.P. 17 1 657±68 - 1 363±57 a B.P. 18 1 362±57– 267±10 a B.P. 19 266±10 a B.P.- present a B.P.In addition to, we can identify some climate events from above climate variety series, such as B?lling-Aller?d, Younger Dryas and 8.2 ka B.P. event. According to the varve chronology from the Erlongwan maar lake, beginning and end age of these events is determined, as follows: B?lling-Aller?d(13 570±362 - 12 598±349 a B.P.) Younger Dryas(12 597±349 - 11 485±316 a B.P.) 8.2 ka B.P. event(8 449±236 - 8 120±227 a B.P.)Up to now, it is the most detailed and actual climatic and environmental variety series in NE, China, which provides the scientific evidence for research the climatic and environmental variety since the last deglaciation. Based on this series, I think, the Holocene start in 11 485 a B.P., which is close with Greenland records(GRIP:11 150 a B.P.;GIPS2:11 640 a B.P.).
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