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collected in the sediment trap. The temporal occurrencesof N. incompta at Station JT associatedwith the meanders of the Kuroshio are consistentwith the high abundance of N. incomptain the surface sediment record from beneath themodern cold water mass off Kishu and Enshunada,between the Japanese coast and the axis ofthe Kuroshio current system.2008040159浮 游 有 孔 虫 演 化 记 录 中 的 分 类 级 别 层 次 结 构证 据 = Evidence of hierarchical organization inthe planktic foraminiferal evolutionary record.( 英 文 ). Patterson R T; Fowler A D. Journal ofForaminiferal Research, 2004, 34(2): 85-95 3 图版 .The Wavelet Transform was used to analyzethe evolutionary record of planktic foraminiferato distinguish specific structure not previouslyresolvable. Both the speciation and extinctionwavelets are characterized by a major singularityat the Cretaceous-Tertiary (K-T) boundary,when there was a total breakdown in the interconnectednessof ecosystems related to sharplyreduced diversity following the Chicxulub impactevent. The speciation wavelet is also characterizedby an interval consisting of a hierarchicalarray of five orders of bifurcation, which arerelated to repeated iterative radiation of speciesfrom the Albian to Maastrichtian. These plankticforaminiferal extinction patterns were related toquasi-periodic orogenic cycles of the Cretaceousthat, in turn, produced episodic mantle CO2-degassing, oceanic volcanism and anoxia, andsea level fluctutations. We hypothesize that thehierarchical structure observed is a reflection ofthis process in an otherwise stochastic system.2008040160森 诺 曼 晚 期 Bonarelli 事 件 前 后 典 型 地 点 浮 游有 孔 虫 和 环 境 变 化 特 征 - 一 个 来 自 特 提 斯 参考 剖 面 ( 意 大 利 中 部 Gubbio 地 区Bottaccione 剖 面 ) 的 高 分 辨 率 研 究 = Planktonicforaminifera and environmental changesacross the Bonarelli event (oae2,latest Cenomanian) in its type area: a high-resolution studyfrom the tethyan reference Bottaccione section(Gubbio,central Italy). ( 英 文 ). Coccioni R;Luciani V. Journal of Foraminiferal Research,2004, 34(2): 109-129 3 图 版 .The worldwide latest Cenomanian OceanicAnoxic Event 2 (OAE2) was investigated for theplanktonic foraminiferal assemblages in the typearea of its sedimentary expression, the Corg–richBonarelli Level (Gubbio, central Italy). The 313kyr preceding the onset of OAE2 and the 153kyr following the end of this event were analyzedin the deep-water setting of the Bottaccionesection (Umbria-Marche Basin). For thefirst time, a high-resolution approach and quantitativemethods were applied. Several events andbiotic changes, including the acme and crisis ofdifferent genera, were recognized. They provideevidence of a progressive and rapid deteriorationof paleoenvironmental conditions, reaching aclimax coincident with the Bonarelli Event, andof the subsequent, gradual (although not complete)recovery. Although no major mass extinctionin planktonic foraminifera occurred acrossthe Bonarelli Event, the extinction of the mostspecialized forms, i.e., the rotaliporids, and Globigerinelloidesbentonensis, is recorded just beforeits onset. The observed pattern of markedchanges in planktonic foraminiferal assemblagesindicates five discrete phases of different degreesof environmental perturbation within themarine ecosystem. Phase I (313–55 kyr prior tothe onset of OAE2) is characterized by a highplanktonic foraminiferal abundance and diversitythat imply a relatively stable environment,with different ecological niches occupied andstratified water column. On the other hand, relativelyhigh percentages of hedbergellids and heterohelicidsindicate a general mesoeutrophicenvironment and a well-developed oxygenminimum zone. Episodes of increased eutrophicconditions are indicated by pulses in abundanceof radiolarians. A well-developed oxygen minimumzone may be related to a long-term changethat precedes the onset of OAE2 (mid-Cenomanian Event). The most dramatic changestook place during Phase II and encompassed thelast 55 kyr preceding deposition of the BonarelliLevel. The onset of a high-stress environment isclearly shown by the shift to a distinctly unstableplanktonic foraminiferal structure, characterizedby low species diversity and marked foraminiferalchanges and events. Some of these tookplace at the same time (the rotaliporid crisis, theheterohelicid decline, the Hedbergella-Schackoina shift, the onset of the ‘large formeclipse’ when > 150 µm forms temporarily disappeared)followed by other sequential events(onset of dwarfism, schackoinid acme, and hedbergellidacme). The above-mentioned changesand events indicate for Phase II an increasedsurface productivity, enhanced oxygen minimumzone, and marked rapid changes of ecologicalparameters (e.g., temperature, salinity, tracemetals). These marked foraminiferal changesculminate at the base of the Bonarelli Level withthe temporary disappearance of all planktonicforaminifera. Phase III (100–900 kyr) coincideswith the Bonarelli Level deposition and is characterizedby highly eutrophic conditions, as indicatedby radiolarian proliferation. Phase IV (35kyr), similar to phase II except for the absence ofrotaliporids, is characterized by the proliferationof the opportunistic hedbergellids and49