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缅 甸 北 部 Hukawng 峡 谷 琥 珀 产 地 的 地 质 =Geology of an amber locality in the HukawngValley, Northern Myanmar. ( 英 文 ). CruickshankR D; Ko Ko. Journal of Asian Earth Sciences,2003, 21(5): 441-455Amber (‘Burmite’) from the Hukawng Valleyof Myanmar has been known since at least the1st century AD. It is currently being producedfrom a hill known as Noije Bum, which was firstdocumented as a source of amber in 1836. Severalgeologists visited the locality between 1892and 1930. All of them believed that the hostrocks to the amber are Tertiary (most said Eocene)in age, and this conclusion has beenwidely quoted in the literature. However, recentwork indicates a Cretaceous age. Insect inclusionsin amber are considered to be Turonian–Cenomanian, and a specimen of the ammoniteMortoniceras (of Middle-Upper Albian age) wasdiscovered during the authors' visit. Palynomorphsin samples collected by the authors suggestthat the amber-bearing horizon is UpperAlbian to Lower Cenomanian. The preponderanceof the evidence suggests that both rocksand amber are most probably Upper Albian. Thisdetermination is significant for the study of insectevolution, indicating that the oldest knowndefinitive ants have been identified in this amber[American Museum Novitates 3361 (2002) 72].This site occurs within the Hukawng Basin,which is comprised of folded sedimentary(±volcanic) rocks of Cretaceous and Cenozoicage. The mine exposes a variety of clastic sedimentaryrocks, with thin limestone beds, andabundant carbonaceous material. The sedimentswere deposited in a nearshore marine environment,such as a bay or estuary. Amber is foundin a fine clastic facies, principally as disk shapedclasts, oriented parallel to bedding. A minorityoccurs as runnels (stalactite shaped), with concentriclayering caused by recurring flows ofresin. An Upper Albian age is similar to that ofOrbitolina limestones known from a number oflocations in northern Myanmar. One of these, atNam Sakhaw, 90 km SW of Noije Bum, has alsobeen a source of amber.2008040533关 于 三 叠 纪 底 部 全 球 层 型 剖 面 和 点 位 = Onthe global stratotype section and point of theTriassic base. ( 英 文 ). Sadovnikov G N. Stratigraphyand Geological Correlation, 2008, 16(1):31-46A unique succession of volcanogenic depositswith representative paleontological remainscharacterizing the Permian-Triassic boundaryinterval in the North Siberian platform and Taimyris described. The succession is suitable forselecting a standard for the Triassic base innonmarine deposits. Abundant and diverse fossilsoccurring in the succession evidence thatvolcanism responsible for origin of the plateaubasalt province in Siberia was not a brief epochof paroxysmal eruptions, which eliminated everythingalive. Throughout the formation historyof relevant plateau basalts, the organic world ofthe plateau and around existed and graduallyevolved.2008040534北 极 区 早 侏 罗 世 至 阿 林 阶 古 生 物 地 理 : 微 底栖 生 物 ( 有 孔 虫 和 介 形 类 ) 的 意 义 = TheEarly Jurassic to Aalenian paleobiogeography ofthe Arctic realm: Implication of microbenthos(Foraminifers and Ostracodes). ( 英 文 ).Nikitenko B L. Stratigraphy and GeologicalCorrelation, 2008, 16(1): 59-80Stages in evolution of the Early Jurassic toAalenian foraminifers and ostracodes are establishedbased on the analyzed diversity dynamicsof respective microfauna associations. Evolutionof foraminifers is divided in two, the Hettangianinitialearly Toarcian and the late early Toarcian-Aalenian stages, while the identical first stage inevolution of ostracodes has been followed by thelate early Toarcian-Callovian stage. During theJurassic, periodic migrations of foraminiferaland ostracod genera and species, which wereinterrelated with large transgressions and climaticchanges, took place in the initial late andmid-late Pliensbachian, initial early Toarcian,and the late Toarcian-early Aalenian. Being isolatedto the maximum extent in the second halfof the late Aalenian, the Arctic basin lost connectionswith seas of northwestern Europe. TheEarly Jurassic to Aalenian biogeography of theArctic basin is established based on the results ofcluster analysis (group average link method, Jaccardcoefficient, presence or absence of foraminifersand ostracodes genera) with due accountfor preceding and subsequent formationhistory of microbenthos structure in biochores.The distinguished biochores are ranked asrealms and provinces of foraminifers and ostracodes.As is established, contours of the realmsand provinces populated by different groups ofmicrobenthos did not coincide and changed withtime. Ecotones between the realms (e.g., theNorth Sea province) changed their localitizationto be a part of the Arctic or Boreal Atlanticrealms in different epochs. The Early-MiddleJurassic sedimentary successions of the Arcticbasins reveal several levels of sharp taxonomicchanges in composition of microbenthos underinfluence of the first-order abiotic factors.2008040535西 西 伯 利 亚 北 极 地 区 白 垩 纪 - 古 近 纪 界 线 沉 积的 有 孔 虫 生 物 地 层 学 = Biostratigraphy of theCretaceous-Paleogene boundary deposits in the162