An international cooperative study of the Late Cretaceous biota and non-marine strata including the Cretaceous-Paleogene ( K--Pg) boundary in Jiayin near the Heilongjiang River，China during 2002-2010，is summarized in this paper． The strata includes the Upper Cretaceous Yong'ancun-，Taipinglinchang-，Yuliangzi-， and Furao formations，and the Paleocence Wuyun Formation consisting of Baoshantou Member and a Coalbearing Member． Seven palynological assemblages from Santonian to Paleocene are recognized，which is used for definition of the K--Pg boundary． Through the palynological analysis of three drilled boreholes ( XHY-2005， 2006，2008) in Xiaoheyan of western Jiayin，the K--Pg boundary is defined within 20. 00-20. 05 m in the borehole XHY-2006 ( as a standard boundary) which is just between the top of Furao Formation ( late Maasterichtian) and the base of Baishantou Member ( early Danian) ． These new research results are supported by paleomagnetic， geochemical and other analyses，also． On the other hand，the presence of eight taxa of Maasterichtian dinosaurs ( mostly hadrosaurids) have been recognized by the authors; and two mega-plant assemblages from the Yong'ancun Fm ( Santonian) to Taipinglinchang Fm ( Campanian) are confirmed． These research achievements indicate that the Upper Cretaceous-Paleocene in Jiayin can be well correlated to the strata in the neighboring Zeya-Bureja basin，Russia． The K--Pg boundary definited in Jiayin is the first well documented non-marine K--Pg boundary in China． Also the related paleoclimate，paleoenvironment and the mass extinctions in this area during the Cretaceous-Paleocene transition are also discussed．

It was conducted the comparison of palynological assemblages of the Middle Tsagayan，Upper Tsagayan subformations，Furao and Wuyun formations from Zeya-Bureya Basin of Amur ( Heilongjiang) River region with assemblages obtained from the marine deposits of Northeast Russia，Sakhalin，Kuril，and Hokkaido Islands，dated by ammonites，foraminifers and other invertebrates． Based on detail correlation，the geological age of the terrestrial beds was defined． The guide fossils are recognized Marsypiletes cretacea，Tricolpites variexinus， Aquilapollenites conatus，A． stelkii，A． rombicus，Integricorpus bellum，Pseudointegricorpus clarireticulatus， Triprojectus amoenus，Orbiculapollis lucidus，Wodehouseia aspera，Quercoidites minor，which had last occurrence in the late Maastrichtian． The Danian palynofloras usually are dominated by Triatriopollenites plicoides and T． confusus． The species Anacolosidites subtrudens，Aquilapollenites proceros，A． spinulosus have last occurrence in the Danian． The K-T ( K-Pg) boundary in the terrestrial deposits is defined in the base of the Upper Tsagayan Subformation and the base of the lower part of the Wuyun Formation． The latter is represented by aleuropelite to fine-grained sandstones． The change of taxonomical composition of palynospectra in similar environments could be determined by real change of flora at the Mesozoic and Cenozoic boundary，but not by changes of lithological facies or depositional environment，generally．

Four main dinosaur-bearing sites have been investigated in latest Cretaceous deposits from the Amur / Heilongjiang Region: Jiayin and Wulaga in China ( Yuliangze Formation) ，Blagoveschensk and Kundur in Russia ( Udurchukan Formation) ． More than 90% of the bones discovered in these localities belong to hollow-crested lambeosaurine hadrosaurids: Charonosaurus jiayinensis at Jiayin，Amurosaurus riabinini at Blagoveschensk， Olorotitan arharensis at Kundur，and Sahaliyania elunchunorum at Wulaga． Flat-headed hadrosaurine hadrosaurids are much less numerous，but appear well diversified as well: Kerberosaurus manakini at Blagoveschensk， Wulagasaurus dongi at Wulaga，and a new genus at Kundur． Theropods are represented by shed teeth and isolated bones; isolated scutes and teeth discovered at Kundur are tentatively attributed to nodosaurids． Palynological studies suggest that these sites are probably synchronous with the Lancian' vertebrate localities of western North America，which represent the youngest dinosaur faunas in this area． However，the latest Cretaceous dinosaur assemblages are completely different in the Amur /Heilongjiang region ( lambeosaurines abundant，ceratopsids absent) and in western North America ( ceratopsids abundant，lambeosaurines extremely rare or absent) ． This probably reflects some kind of geographical barrier between both areas by Maastrichtian time rather than strong differences in palaeoecological conditions．

Fossil woods were collected from the Upper Cretaceous to Paleocene beds distributed around Heilongjang ( Amur) River area of China and Russia． A total of 43 specimens were collected from Baishantou，Longgushan， and Yong ＇ancun in Jiayin，China，and 85 specimens from Zeya-Bureya Basin lying southeast of Blagoveshchensk in Russia． Selected specimens were sectioned and studied anatomically． The source deposits of almost all identifiable specimens belong to the Upper Cretaceous ( Campanian) Taipinglinchang Formation and the Paleocene Wuyun Formation in China，and the Paleocene Upper Tsagayan Formation in Russia． Although the results obtained are still far from complete，the taxonomic composition of the fossil woods show marked stratigraphic differences between the two horizons beyond the K/T boundary in China． There is also a strong similarity in wood flora between the Wuyun Formation of China and the Upper Tsagayan Formation of Russia． All identified specimens from the Taipinglinchang Formation are Xenoxylon latiporosum． This is one of the stratigraphically younger records of Xenoxylon，which is a conifer morphogenus of uncertain affinity most common in the Triassic to Early Cretaceous． Only one specimen with possible derivation from either the Wuyun or the Maastrichtian Furao Formation in China was identified as Taxodioxylon sp． The Wuyun Formation yielded both conifers and dicotyledonous woods． The conifers include Taxodioxylon sequoianum of the Taxodiaceae，and Protopiceoxylon amurense，which is attributable to the extant genera Keteleeria or Nothotsuga of the Pinaceae， both are at present endemic to China． At least two morphotypes of dicotyledonous woods were recognized，with one identified as cf． Hamamelidoxylon ，and the other diffuse porous wood is characterized by numerous heterogeneous rays． From the Zeya-Buleya Basin of Russia，Taxodioxylon sequoianum and cf． Hamamelidoxylon sp． were identified from the Upper Tsagayan Formation． The similarity of wood composition in both Wuyun and Upper Tsagayan Formations support lithological as well as biostratigraphic correlations proposed for the two formations．