POLLEN AND SPORE STRATIGRAPHY OF A MOLLIC HAPLUDALF (DEGRADED CHERNOZEM) IN NORTHEASTERN KANSAS

Palynological analyses were completed for the A and B horizons of a forested Mollic Hapludalf to determine type, amount, and distribution of pollen and spores within the soil solum. Hypotheses regarding the origin of pollen and the mechanisms of its movement within soil bodies are also advanced. Pollen downwash within the mineral soil seems to be very slow and confined to the uppermost porous and most homogenized part of the solum. The predominance of non-arboreal pollen at depth was believed to be a result of deposition with the loess parent material. High arboreal pollen frequencies in the upper horizons coupled with increases in non-arboreal types at depth indicate gradual ongoing mixing from the present vegetation into the soil.     

Climatic deterioration and the end of the Gortian Interglacial in sediments from Derrynadivva and Burren Townland,near Castlebar,County Mayo,Ireland

Pollen and macrofossil analyses of two sequences of organic sediment in western Ireland have allowed the recognition of the latter parts of the Gortian Interglacial, a Middle Pleistocene temperate stage. The palaeobotanical information from the two sites identifies the preservation of partial sequences from the Gortian Interglacial (believed to be the equivalent of the Hoxnian Stage of Britain and the Holsteinian of Europe). The pollen and macrofossil data from one of the sites, Derrynadivva, span the middle and latter parts of the temperate stage. The results show that fire influenced the vegetation throughout the middle part of the temperate stage, and the termination of the organic depositional sequence appears to have been due to environmental deterioration. The former is identified through the abundant occurrence of charcoal in the sediments, whereas the latter is apparent in the sediment sequence and in the reworking of thermophilous pollen types into the upper part of the deposit. The second site, Burren Townland, records only part of the later zones of the interglacial, but the ericaceous assemblages of the latter part of the Gortian Interglacial are well developed and well preserved. Macrofossil analyses and scanning electron microscopy work on the pollen at the latter site has allowed the recognition of Rhododendron ponticum, adding to previous records of this species, which now has a very disjunct European distribution.     

红树林孢粉-气候因子转换函数恢复古环境的可行性初探

红树林是一种对温、盐、流及土质等均具严格要求的植被类型，对定量化研究热带，亚热带沿海地区古环境具有重要的意义，通过对广西英罗湾、北海洞尾的红树林表土中孢粉的研究，初步建立起红树林植物孢粉-气候因子的转换函数，将之运用到位于英罗湾的典型钻孔D325的孢粉资料中，获得该孔所记录的年平均温度，最高温度，最低温度，年降雨量以及最高盐度等气候环境指标的变化，同时，与由孢粉分析获得的D325孔记录的全新世以来的7个气候变化阶段相对比，发现具有很好的对应关系，说明利用对环境反映灵敏的红树林孢粉为信息源，建立与环境气候因子的关系，定量恢复环境具可行性。     

Late quaternary glacial stades in the Cordillera Central,Colombia, based on glacial geomorphology,tephra–soil stratigraphy,palynology, and radiocarbon dating

Using data from glacial geomorphology, tephra–soil stratigraphy and mineralogy, palynology, and radiocarbon dating, a sequence of glacial and bioclimatic stades and interstades has been identified for the last ca. 50000 yr in the Ruiz-Tolima massif, Cordillera Central, Colombia. Six Pleistocene cold stades separated by warmer interstades occurred: before 48000, between 48000 and 33000, between 28000 and 21000, from ≥16000 to ca. 14000, ca. 13000–12400, and ca. 11000–10000 yr BP. Although these radiocarbon ages are minimum-limiting ages obtained from tephra layers on top of tills, the tills are not significantly older because most are bracketed by dated tephra sets in measured stratigraphic sections. Two minor moraine stages likely reflect glacier standstill during cold intervals ca. 7400 yr BP and slightly earlier. Finally, glaciers readvanced between the seventeenth and nineteenth centuries. In contrast to the ice-clad volcanoes of the massif, ca. 34 km² in area above an altitude of ca. 4800 m, the ice cover expanded to 1200 km² during the Last Glacial Maximum (LGM) and was still 800 km² during Late-glacial time (LGT). Glacier reconstructions based on the moraines suggest depression of the equilibrium line altitude (ELA) by ca. 1100 m during the LGM and 500–600 m during LGT relative to the modern ELA, which lies at ca. 5100 m in the Cordillera Central. Glaciers in this region apparently reached their greatest extent when the climate was cold and wet, e.g. during stades corresponding to Oxygen Isotope Stage 3; glaciers were still expanding during the LGM ca. 28000–21000 yr BP, but they shrank considerably after 21000 yr BP because of greatly reduced precipitation. © 1997 John Wiley & Sons, Ltd.     

长江三角洲(江南)地区新近纪地层划分及时代讨论

根据对长江三角洲 (江南 )地区多年来积累的古地磁、孢子花粉、微体生物化石、同位素测年等资料的重新研究 ,并结合岩性特征、地层层序进行区域地层对比 ,发现区内新近纪地层较齐全 ,自下而上将新近系层序厘定为中新统洞玄观组 (N1 d) /白龙港组 (N1 b)、六合组 (N1 l) ,上新统新建干窑镇组 (N2 g) ,并将第四纪 /新近系界线划在磁性地层极性柱的 M/ G之间 (距今大约 2 .6 Ma)。     

The Permian Kas Formation of SE Turkey—palynological correlation with strata from Saudi Arabia and Oman

The Kas Formation in SE Turkey was deposited as part of the Permian sequence on the northern margin of the Arabian Plate. Its stratigraphic relationship to time‐equivalent strata of the Arabian Plate was mentioned briefly in previous studies, but has not been elaborated and illustrated in detail. This biostratigraphic review of existing palaeontological data has improved the accuracy of age interpretation for the Kas Formation, and the relationship of its excellent palynological record to the international Permian chronostratigraphic units. As a result, this study has identified a number of key palynological species from the Kas Formation, which occur as well as in the ‘Basal Khuff Clastics’ of Saudi Arabia and in the ‘Khuff transition section’ of Oman. All these units have approximately the same age: Wordian to early Capitanian, based on ‘age control’ provided by Foraminifera. This study also demonstrates that, by using key palynological taxa, correlation of strata would be possible across the entire Arabian Plate in this narrow time range. Hence, the ‘Oman and Saudi Arabia Palynological Zone 6’ (OSPZ6) is applicable throughout the Arabian Plate area, including the northern regions of SE Turkey and Iraq. Copyright © 2011 John Wiley & Sons, Ltd.     

Stratigraphy of the Triassic?Jurassic Boundary Successions of the Southern Margin of the Junggar Basin, Northwestern China

The Triassic?Jurassic (Tr?J) boundary marks a major extinction event, which (~200 Ma) resulted in global extinctions of fauna and flora both in the marine and terrestrial realms. There prevail great challenges in determining the exact location of the terrestrial Tr?J boundary, because of endemism of taxa and the scarcity of fossils in terrestrial settings leading to difficulties in linking marine and terrestrial sedimentary successions. Investigation based on palynology and bivalves has been carried out over a 1113 m thick section, which is subdivided into 132 beds, along the Haojiagou valley on the southern margin of the Junggar Basin of the northern Xinjiang, northwestern China. The terrestrial Lower Jurassic is conformably resting on the Upper Triassic strata. The Upper Triassic covers the Huangshanjie Formation overlaid by the Haojiagou Formation, while the Lower Jurassic comprises the Badaowan Formation followed by the Sangonghe Formation. Fifty six pollen and spore taxa and one algal taxon were identified from the sediments. Based on the key-species and abundance of spores and pollen, three zones were erected: the Late Triassic (Rhaetian) Aratrisporites?Alisporites Assemblage, the Early Jurassic (Hettangian) Perinopollenites?Pinuspollenites Assemblage, and the Sinemurian Perinopollenites?Cycadopites Assemblage. The Tr?J boundary is placed between bed 44 and 45 coincident with the boundary between the Haojiagou and Badaowan formations. Beds with Ferganoconcha (?), Unio?Ferganoconcha and Waagenoperna?Yananoconcha bivalve assemblages are recognized. The Ferganoconcha (?) bed is limited to the upper Haojiagou Formation, Unio?Ferganoconcha and Waagenoperna?Yananoconcha assemblages are present in the middle and upper members of the Badaowan Formation. The sedimentary succession is interpreted as terrestrial with two mainly lake deposit intervals within Haojiagou and Badaowan formations, yielding fresh water algae and bivalves. However, the presence of brackish water algae Tasmanites and the marine?littoral facies bivalve Waagenoperna from the Badaowan Formation indicate that the Junggar Basin was influenced by sea water caused by transgressions from the northern Tethys, during the Sinemurian.     

Floral biodiversity and geology of the Talcher Basin,Orissa, India during the Permian–Triassic interval

The review paper provides an updated account of the previous and recently published records concerning the palaeobiology and the geology of the Talcher Basin of Orissa State, India. We conclude that fossil floral species in this basin originated in the earliest Permian Talchir Formation and evolved and diversified through the Karharbari Fm., Barakar Fm., Barren Measures Fm. and the uppermost Kamthi Fm. (Late Permian–Triassic). The megaflora and the palynology of the different formations of the basin are also discussed briefly. The geological setting of the basin along with the status of different formations (especially the Kamthi Formation) has been redefined. The post‐Barakar Fm. rocks, earlier retained in the Raniganj/Kamthi, Panchet and Mahadeva formations in this basin, have been critically assessed and redefined as the Lower and Upper Kamthi formations of Late Permian and Triassic ages, respectively. Accordingly, the geological map of the basin has been modified. Permian deposits (particularly the Barakar and the lower Kamthi formations) not only have the best preserved flora but also possess the highest diversity, whereas the upper Kamthi Triassic sediments have a meagre number of taxa. The plant diversity of the basin has been discussed in detail to interpret the development of the flora, evolutionary trends and palaeoenvironments of the basin. The patchy Gangamopteris vegetation of the Talchir glacial phase has ultimately evolved and diversified through time (Karharbari Fm. to Lower Kamthi Fm.) and gave rise to the thick dense swampy forests consisting of large Glossopteris trees and other shade‐loving under‐storied pteridophytes. Several groups of plants including spores and pollen have disappeared in a ladder pattern during the Permian–Triassic interval (Lower Kamthi–Upper Kamthi Fm.) and, similarly, in steps, many new fore‐runners appeared in the Upper Kamthi Formation. Records of marine acritarchs and ichnofossils in this basin at various Permian–Triassic levels demonstrate that there were marine influences. These features suggest a paralic (coastal marine to deltaic) mode of origin of the coal beds and associated sediments in the basin. The present study also advocates the continued survival of plants, rather than a mass extinction near the vicinity of the Permian–Triassic (P–T) boundary in this basin. Copyright © 2012 John Wiley & Sons, Ltd.     

Mesozoic (Late Jurassic) palynomorphs and charcoal from a sandstone pebble from Quaternary glacial deposits of the North Sea

The palynological contents as well as macroscopic charcoal fragments from a calcareous sandstone pebble from Quaternary glacial deposits of the North Sea (80 km SW of the Dogger Bank) are described. The taxonomic composition of the palynoflora points to a Late Jurassic (or Late Jurassic/Early Cretaceous) age of the sandstone. The charcoal is interpreted as direct evidence of palaeo‐wildfire occurring during this period in the source area of the sediments of this particular sandstone. This finding, together with already published data on Mesozoic deposits, allows to conclude that wildfires were obviously widespread during this period in the area of the modern day North Sea and adjacent areas. Copyright © 2012 John Wiley & Sons, Ltd.     

内蒙银根-额济纳旗盆地白垩系中硅化木化石及其沉积环境

内蒙古银根 额济纳旗盆地是我国北方重要的中－新生代陆内含油气盆地,主要出露白垩系冲洪积 河湖相碎屑岩及火山岩夹层。本文描述了在盆地东南部下白垩统巴音戈壁组下段（1号）和苏红图组二段底部（2号）发现的上、下两处原始埋藏的硅化木化石,并探讨了早白垩世时期盆地沉积时的气候环境。两处化石均保存完好,表面结构较为完整。巴音戈壁组上部和苏红图组下部泥岩段孢粉分析结果显示地层时代为早白垩世中晚期。同时,孢粉植物群揭示该时期银根 额济纳旗盆地气候环境温暖湿润,植被茂盛。根据化石保存特征和产出位置的地层岩性,初步推测1号硅化木化石点系冲洪积物快速堆积所致,2号硅化木化石点系火山喷发物瞬间埋藏所致,其埋藏时代大致为早白垩世晚期。