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adyana. The strong currents and tides of theAmazon shelf could cause large tests to movealong the seabed by bed-load transport processes.In living foraminifera, such tests may break andlater regenerate abnormally. Such occurrencesvary stratigraphically and geographically, demonstratinghydrodynamic variations in time andspace.2008040180伊 朗 中 部 Abadeh 地 区 Surmaq 组Yahtashian 阶 至 Midian 阶 蜓 类 的 古 生 物 地理 分 析 = Paleobiogeographic analysis ofYahtashian to Midian Fusulinacean faunas of theSurmaq Formation in the Abadeh region, CentralIran. ( 英 文 ). Kobayashi F; Ishii K-I. Journal ofForaminiferal Research, 2003, 33(2): 155-165 3图 版 .Fusulinaceans consisting of 56 species assignableto 30 genera are distinguished in the SurmaqFormation in the Abadeh region, centralIran. Based on the stratigraphic distribution offusulinaceans, the Surmaq Formation is divisibleinto six biostratigraphic zones from lower toupper: Darvasites ordinatus, Pseudofusulinaquasifusuliniformis, Eopolydiexodina percica,Afghanella schencki, Neoschwagerina occidentalis,and Chusenella abichi. Faunal compositionand comparison between the Abadeh region,South West Asian, and Mediterranean Sea regionsindicates that the first zone is Yahtashianin age, the second and third are definitely indeterminable,the fourth and fifth are Murgabian,and the last is Midian. Fusulinacean faunas ofthe Pseudofusulina quasifusuliniformis, Eopolydiexodinapersica, and Chusenella abichiZones are less diversified compared to the twointervening zones which have many neoschwagerinidsand verbeekinids. The Surmaq fusulinaceans,characterized by Eopolydiexodina andAfghanella, are one of the most widely representedMiddle Permian faunas in the South WestAsian and Mediterranean Sea regions, belongingto the western part of the Western Tethyan paleobiogeographicprovince. Murgabian andMidian faunas in this province differ from thoseof the eastern Tethyan Province in having onlyrare occurrences of Colania and Lepidolina, andfrom the Panthalassan Province in having Afghanellaand Sumatrina. Permian carbonatedeposition began in Yahtashian time throughoutthe Cimmerian terranes including the Abadehregion. Differences in fusulinacean faunal compositionand species diversity in the SurmaqFormation are closely associated with differencesin limestone lithologies. For example, theChusenella abichi Zone is present mostly inlime-mudstone and wackestone that are partlydolomitized. These paleobiogeographic andlithologic chararacters have implications for thenorthward movement of this tectonic provenance,for the rift-drift-collision history of the westernpart of the Cimmerian Continent, and also forthe evolution and extinction of fusulinaceans inPermian time.2008040181墨 西 哥 加 利 福 尼 亚 Baja 地 区 San antonio delmar 剖 面 Rosario 组 晚 白 垩 世 有 孔 虫 、 古 环境 和 古 海 洋 学 = Late Cretaceous foraminifera,paleoenvironments, and paleoceanography of theRosario Formation, San antonio del mar, bajacalifornia, Mexico. ( 英 文 ). Maestas Y; MacleodK G; Douglas R; Self-Trail J; Ward P D. Journalof Foraminiferal Research, 2003, 33(3): 179-191 3 图 版 .The 315m of Rosario Formation exposed atthe San Antonio del Mar (SADM) section (BajaCalifornia, Mexico) contains moderately-to-wellpreserved benthic and planktic foraminifera, calcareousnannofossils, and molluscs. Nannofossilssuggest most of the SADM section was depositedwithin a narrow interval of the late Campanian(CC21-CC22), whereas foraminifera andmolluscs suggest a younger maximum age(younger than the Globotruncana ventricosaZone) and allow deposition over a longer intervalof time. Planktic foraminifera at SADM representcommon Tethyan taxa. They are largelyrestricted to the lower and middle portions of thesection and comprise 0-~40% of foraminiferalassemblages. Stable isotopic analyses ofRugoglobigerina rugosa yield 18Ov-PDB valuesfrom –2.27 to –2.82 corresponding to salinitycorrectedpaleotemperature estimates of 26–30°C for the Late Cretaceous eastern Pacific.These estimates are as warm as modern tropicaltemperatures and are similar to tropical paleotemperatureestimates from 18O analyses of exceptionallypreserved Maastrichtian samples;however, they are considerably warmer thanmost tropical Campanian-Maastrichtian estimates.Benthic foraminifera indicate outer shelfpaleo-depths with a slight increase in depth ordecrease in benthic oxygen levels in the upperparts of the interval studied. The change in thebenthic assemblage corresponds to an ~1 positiveshift in benthic O18, suggesting a relationshipbetween benthic assemblages and an inferredincrease in the local intensity of upwelling.2008040182委 内 瑞 拉 Cariaco 盆 地 浮 游 有 孔 虫 变 迁 和 群落 组 成 的 季 节 性 和 年 内 变 化 = Seasonal andinterannual variations in planktonic foraminiferalflux and assemblage composition in theCariaco basin,Venezuela. ( 英 文 ). Tedesco K A;Thunell R C. Journal of Foraminiferal Research,2003, 33(3): 192-21057