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More than 200 km from shore, calcareous siltyclaystone predominates, whereas 100 to 200 kmoffshore, mudstone and siltstone predominate.From about 30 to 100 km offshore, centimetrebeddedvery fine sandstone and mudstone recordalong-shelf (SSE)-directed storm-generatedgeostrophic flows. Five to thirty kilometres fromshore, decimetre-bedded hummocky crossstratifiedfine sandstone and mudstone recordstrongly oscillatory, wave-dominated flowswhereas some gutter casts indicate shore-oblique,apparently mostly unidirectional geostrophicflows. Nearshore facies are dominated by swaleycross-stratified or intensely bioturbated cleanfine sandstone, interpreted as recording, respectively,areas strongly and weakly affected bydischarge from distributary mouths. Shorefacesandstones grade locally into river-mouth conglomeratesand sandstones, including conglomeratechannel-fills up to 15 m thick. Locally,brackish lagoonal shelly mudstones are presenton the extreme western margin of the basin.There is no evidence for clinoform stratification,which indicates that the Kaskapau sea floorhad extremely low relief, lacked a shelf-slopebreak, and was probably nowhere more than afew tens of metres deep. The absence of clinoformsprobably indicates a long-term balancebetween rates of accommodation and sedimentsupply. Mud is interpreted to have been transported>250 km offshore in a sea-bed nepheloidlayer, repeatedly re-suspended by storms. Finegrainedsediment accumulated up to a ‘mud accommodationenvelope’, perhaps only 20 to40 m deep. Continuous re-working of the seafloor by storms ensured that excess sedimentwas redistributed away from areas that had filledto the ‘accommodation envelope’, being depositedin areas of higher accommodation furtherdown the transport path. The facies distributionsand stratal geometry of the Kaskapau shelfstrongly suggest that sedimentary facies, especiallygrain-size, were related to distance fromshore, not to water depth. As a result, the ‘100 to>300 m’ depth interpreted from calcareous claystonefacies for the more central parts of the InteriorSeaway, might be a significant overestimate.2008040543海 地 富 含 小 球 体 沉 积 的 时 代 、 化 学 地 层 和 生物 地 层 : 多 事 件 K–T 景 象 = Age, chemo- andbiostratigraphy of Haiti spherule-rich deposits: amulti-event K–T scenario. ( 英 文 ). Keller G;Adatte T; Stinnesbeck W; Stüben D; Berner Z.Canadian Journal of Earth Sciences, 2001,38(2): 197-227Examination of two new expanded K–T transitionsand reexamination of road outcrops nearBeloc, Haiti, reveals that deposition of the glassspherule-rich deposit (SRD) occurred within theearly Danian Parvularugoglobigerina eugubina(Pla(1)) Zone, followed by an Ir anomaly, and50 cm above it, a second Pd-dominated platinumgroup element (PGE) anomaly. The K–T boundaryis at an erosional unconformity between thebase of the SRD and underlying Maastrichtianlimestone, where an interval representing about100–250 thousand years appears to be missing(juxtaposition of planktic foraminiferal zones(Pla(1)) and Plummerita hantkeninoides (CF1)).It is possible that the spherule layers are reworkedfrom original deposits at or below theK–T boundary. The Ir anomaly is of roughlychondritic-type and compatible with an impactevent, whereas the Pd-dominated PGE anomalyis a more basalt-type and compatible with amagmatic origin. This suggests a multi-eventscenario consistent with one impact followed bya major volcanic event in the Caribbean or elsewhere2008040544美 国 墨 西 哥 湾 北 部 侏 罗 纪 和 白 垩 纪 海 进 和 海退 旋 回 = Jurassic and Cretaceous Transgressive-Regressive(T-R) Cycles, Northern Gulf ofMexico, USA. ( 英 文 ). Mancini E A; Puckett TM. Stratigraphy, 2005, 2(1): 31-48Establishment of a chronostratigraphicframework is fundamental to the correlation ofstrata and for the interpretation ofthe geohistoryof a basin. For the onshore basins in the northernGulfofMexico, an integrated sequence stratigraphicand biostratigraphicapproach has utilityas amethod for establishing such a framework.Eleven transgressive-regressive (T-R) cycles andnumerous biozones are recognized in Jurassicand Cretaceous non-marine, coastal and marineshelf strata of basins of the northern Gulf of-Mexico. The cyclesconsist of a transgressivephase (aggrading and backstepping intervals)and a regressive phase (infilling interval). Cyclerecognitionis based on stratal geometries, thenature of the cycle boundaries, facies stackingpatterns and large-scale shifts in major faciesbelts. Cycles are primarily controlled by thechange inaccommodation space resulting fromstratigraphic base-level changes (eustatic andtectoniceffects) and sediment supply. Utilizingthis integrated approach, 12 regional unconformitiesand 11 surfaces of maximum transgression(regionalmarine flooding surfaces) wereidentified as major events in theMesozoicgeohistory of the northern Gulf ofMexicoregion.The surfaces of maximum transgression havepotential as events for chronocorrelation.2008040545伊 朗 西 北 部 Khoy 杂 岩 构 造 地 层 学 = Tectonostratigraphyof the Khoy Com-165