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Morphology and morphometry of two hybridizing buntings at their hybrid zone in northern Iran reveal intermediate and transgressive morphotypes
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作者 Ali Gholamhosseini Mansour Aliabadian +1 位作者 Till Topfer Glenn-Peter Sætre 《Avian Research》 SCIE CSCD 2023年第4期523-532,共10页
The closely related Black-headed Bunting(Emberiza melanocephala,a western Palearctic lineage)and Red-headed Bunting(Emberiza bruniceps,an eastern Palearctic lineage)hybridize and replace each other south of the Caspia... The closely related Black-headed Bunting(Emberiza melanocephala,a western Palearctic lineage)and Red-headed Bunting(Emberiza bruniceps,an eastern Palearctic lineage)hybridize and replace each other south of the Caspian Sea.The parental species have distinct phenotypes and therefore morphology is useful for assessing hybridization in the contact zone.In the years of 1940 and 1977,quite a few hybrids were collected and studied morphologically.Since then,the hybrid zone appears to have expanded westwards,but there has been a time gap in the collection of morphological data.Here we reanalyze bunting specimens morphologically and compare the historical data with recent data.Morphometric and phenotypic traits from three time periods(1940,1977 and recent)were studied to assess phenotypic variation of hybrids,pattern of hybridization,and transgressive traits in the hybrid zone.Our results show that most of the birds in the hybrid zone exhibit intermediate phenotypes(both colors and morphometric characters),ranging from the pure phenotype of either of the parental species.However,hybridization has also produced novel phenotypes not seen in any of the parents.Using a canonical discriminant function analysis,the morphometric characters separated each parental species and the hybrids quite well.Our results showed morphometric intermediacy of hybrids in accordance with phenotypes.We observe a time trend in which recent hybrids are more similar to Red-headed Buntings phenotypically compared to historical samples.This pattern is likely a signature of a westward expansion of the Red-headed Bunting into the breeding range of the Black-headed Bunting. 展开更多
关键词 Bunting HYBRIDIZATION Intermediate phenotypes transgressive traits
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Transgressive Surface as Sequence Boundary 被引量:1
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作者 YIN Hongfu TONG Jinnan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第2期143-147,共5页
Analysis of the four cases of the sequence boundary (SB)-transgressive surface (TS) relation in nature shows that applying transgressive surfaces as sequence boundaries has the following merits: it improves the method... Analysis of the four cases of the sequence boundary (SB)-transgressive surface (TS) relation in nature shows that applying transgressive surfaces as sequence boundaries has the following merits: it improves the methodology of stratigraphic subdivision; the position of transgressive surface in a sea level curve is relatively fixed; the transgressive surface is a transforming surface of the stratal structure; in platforms or ramps, the transgressive surface is the only choice for determining the sequence boundary; the transgressive surface is a readily recognized physical surface reflected by seismic records in seismostratigraphy. The paper reaches a conclusion that to delineate a SB in terms of the TS is theoretically and practically better than to delineate it between highstand and lowstand sediments as has been done traditionally. 展开更多
关键词 transgressive surface sequence boundary improvement of stratigraphic subdivision
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Fossil fauna and transgressive.sequence from core QC2 in the South Huanghai Sea
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作者 Zhu Xionghua and Lin Hemao Institute of Marine Geology, Ministry of Geology and Mineral Resources, Qingdao, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1990年第4期561-578,共18页
According to palaeoenvironmental analysis on the fossil fauna dominated by Foraminifera and Ostracoda, core QC2 contains 8 marine transgressive beds, called (from up to bottom) Transgressive Beds Ⅰ,Ⅱ, Ⅲ, …,Ⅷ resp... According to palaeoenvironmental analysis on the fossil fauna dominated by Foraminifera and Ostracoda, core QC2 contains 8 marine transgressive beds, called (from up to bottom) Transgressive Beds Ⅰ,Ⅱ, Ⅲ, …,Ⅷ respectively. Together with dating data, the transgressive sequence since 1. 7 Ma B. P. has been established, indicating that the core went through middle and late Early Pleistocene, early and late Middle Pleistocene, early and late (Substages A and B) Late Pleistocene and the Holocene transgressions. Within these 8 transgressions, late Middle Pleistocene, early Late Pleistocene and the Holocene transgressions-had rather strong activities proved by shallow sea (of 50 or 20-50 m water depth) deposits in the prime, while 2 of the 8, during middle Early Pleistocene and late Late Pleistocene (Substage A), were much weaker only with supratidal deposits. The transgressive cycles also differ from each other. Transgressions in the Holocene and in Substage B of late Late Pleistocene are made up of 3 and 2 subcycles of marine ingressions and regressions respectively, but most transgressions only have a single ingressive or regressive sequence. With the core, some important problems concerning, the study of Quaternary transgression such as correlation of transgressive beds and climatic periods and dating of the transgressive beds are discussed in this paper. 展开更多
关键词 Fossil fauna and transgressive.sequence from core QC2 in the South Huanghai Sea CORE QC
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Transgressive Events since the Late Pleistocene in the Yellow River Delta: Grain-size Distribution and Palynological Results
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作者 LU Jingfang LIU Jian +3 位作者 HUANG Wei HU Gang ZHANG Daolai John BIRKS 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第4期1194-1206,共13页
This study deals with the relationship between sea-level changes and paleoclimatic fluctuations based on the analysis of stratigraphy, grain sizes, palynology, and radiometric dating of the Yellow River delta since th... This study deals with the relationship between sea-level changes and paleoclimatic fluctuations based on the analysis of stratigraphy, grain sizes, palynology, and radiometric dating of the Yellow River delta since the Late Pleistocene. Evidence from the sedimentary record, grain sizes, and pollen provides a paleoenvironmental history of the Late Pleistocene from the boreholes of the delta. Based on a combination of grain-size analysis with lithological studies, marine deposit units contain the intervals of 13.85–16.9, 18.5–19.69, 27.9–34.8, 36.4–37.2, 48.4–51.6, and 54.1–55.9 m, and transitional facies units contain the intervals of 10.25–13.85, 16.9–18.5, 19.69–27.9, 34.8–36.4, 37.2–48.4, 51.6–54.1, and 55.9–60 m, compared with fluvial(terrestrial facies) deposit units(3.36–10.25 m). Based on pollen analysis and pollen assemblages, there were three warm-wet periods from 9.1–0.16 ka BP, 16.1–60 ka BP, and 90.1–94.6 ka BP From the top to the bottom of the borehole, the paleoclimate has an evident fluctuation: warm and moist(Holocene Optimum) —cool and dry(Younger Dryas Event)—mild semi cool—cool and dry—warm and moist. There were three warm-wet periods from 9.1–0.16 ka BP, 16.1–60 ka BP, and 90.1–94.6 ka BP, corresponding to the Holocene Optimum stage, MIS 3, and MIS 5, respectively. The warm period allowed monsoonal evergreen and broadleaved deciduous forests that corresponded to Holocene hypsithermal climatic conditions and the Late Pleistocene climatic Optimum. Three warm-wet periods occurred in marine deposit units from 9.1–0.16 ka BP, 60.1–16.1 ka BP, and 94.6–90.1 ka BP. These periods correspond to the Cangzhou transgression, Xianxian transgression, and Huanghua transgression, respectively. From 90.1–60.1 ka BP, 17.5–9.1 ka BP, and 0. 16 ka BP–1855 AD, three dry and cold phases are recognized. The phases indicate the fluvial(flood plain) sedimentary environment, corresponding to cooler and mild dry periods based on palynological results and grain-size distribution. 展开更多
关键词 TRANSGRESSION GRAIN-SIZE POLLEN Late Pleistocene Yellow River Delta
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Self-Discovery anda Sense of Wholeness in the Transgressive Auto/biogrAfrical Discourses of African American Women Writers
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作者 U.H.Ruhina Jesmin 《Fudan Journal of the Humanities and Social Sciences》 2022年第1期143-158,共16页
The paper attempts to explore selected African American women writers'(Zora Neale Hurston,Maya Angelou,Audre Lorde,and Alice Walker)self-discovery,celebration of their selfhood,and sense of wholeness in their auto... The paper attempts to explore selected African American women writers'(Zora Neale Hurston,Maya Angelou,Audre Lorde,and Alice Walker)self-discovery,celebration of their selfhood,and sense of wholeness in their auto/biogrAfrical discourses.Instrumental rhetoricity of the autobiographers reflects politicization of black women's struggle,cultural(de)construction,and feminist/womanist(re)construction Instead of fitting into heteronormative discourses and aprocess of cultural assimilation,and of adhering to cultural codes of femininity,these writers transgress traditional norms of behavior Through autobiographical manifestos interwoven with self-defining identity and artistic transgression they powerfully assert notions of collective female agency and embrace their new-found identity as feminist womanistqueer.As an agent of awareness and proclamation,their(except Hurston's)powerful rhetoric is infused with their triple consciousness of being a black woman with African background and cultural pride.They illustrate an interconnectedness of racism and sexism which causes double oppression on black women.They boldly raise racial issues of universal significance,stick to their authentic selves,and reaffirm their agonizing black history/past as they journey toward maturity and wholeness.Their discourses reflect an interweaving of past and present,individual and community,and personal and political changes which lead them toward an esthetic paradigmof wholeness. 展开更多
关键词 Auto-biogrAfrican discourse Transgression Self-discovery Wholeness Female agency
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The Mamfe Basin in the southern Benue trough extension between Cameroon and Nigeria:Gem origin and problem of lithostratigraphic nomenclature and marine transgression
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作者 Milan Stafford Tchouatcha Primus Tamfuh Azinwi +4 位作者 Christel Sobdjou Kemteu Augustin Desire Balla Ondoa Leopold Darlus Ngantchu Basil Azeh Anong Courage Gabvourta 《Acta Geochimica》 EI CAS CSCD 2023年第3期495-516,共22页
The Mamfe Basin has been the subject of many studies,but some debates persist,especially concerning the stratigraphic nomenclature,corundum origin,and marine transgression.The aims of this work are(1)to propose a new ... The Mamfe Basin has been the subject of many studies,but some debates persist,especially concerning the stratigraphic nomenclature,corundum origin,and marine transgression.The aims of this work are(1)to propose a new lithostratigraphic nomenclature of the Mamfe Basin formation based on new field observations,(2)to determine the source rock distribution and the origin of gem deposits and(3)to correlate the Cameroon section of the Mamfe Basin with the Nigerian deposits.The main results show that the name Manyu River Group is more appropriate as the Manyu River crosses all the facies in the Mamfe sedimentary Basin belonging to the Manyu Division.According to the facies analysis,the age of deposition,the mineralogic and geochemical data such as the V vs.Al2O3andΣREE vs.Al_(2)O_(3),TiO_(2)MgO,Na_(2)O,P_(2)O_(5),and CaO diagrams,this Group is composed of at least five Formations,including four Cretaceous Formations,from bottom to top:the Etoko Formation(alluvial and fluvial channel to fluvio-lacustrine deposits),the Nfaitok Formation(lagoonal deposits),the Bachuo Ntai Formation(fluvial braided channels or fluvio-deltaic environment)and the Eyumojock/NsanaragatiFormation(fluvio-lacustrine deposits)and the new Cenozoic Formation named Bakebe Formation(fluvio-lacustrine deposits).The gem minerals such as corundum,rutile,or tourmaline in the Cretaceous deposits of the Mamfe Basin are mainly detrital as indicated by the presence of worn shapes and fragments of these minerals.The presence of sapphire in the AlboCenomanian deposits indicates a Precambrian age of the felsic source rock,likely the plutonic rocks such as granite or pegmatite as indicated by the abundance of tourmaline and high LREE/HREE ratios(14.81–34.29)and slightly negative and positive Eu anomalies(0.85–1.15).This marine incursion in the Mamfe Basin was probably from West Nigeria,according to the geographic location of the Mamfe Basin and the general palaeogeographic evolution of the Benue Trough. 展开更多
关键词 LITHOSTRATIGRAPHY Marine transgression Heavy minerals SAPPHIRES Mamfe Basin Benue Trough
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The Effect of Perceived Anonymity on Online Transgressions:The Moderating Role of Moral Excuses
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作者 ZHANG Qianju 《Psychology Research》 2023年第6期246-252,共7页
With the development of science and technology,the use of the Internet is becoming more and more widespread.However,with the popularity of the Internet,some problems have gradually surfaced.The anonymity of Internet u... With the development of science and technology,the use of the Internet is becoming more and more widespread.However,with the popularity of the Internet,some problems have gradually surfaced.The anonymity of Internet use has become a breeding ground for many acts that are contrary to public decency,and this study is conducted against this background.This study explored the impact of perceived anonymity on online transgressions and investigated the moderating effect of moral excuses.A total of 414 subjects,210 males and 204 females,participated in this experimental survey.The SPSS data analysis concluded that perceived anonymity played a significant positive predictive role on online deviance(p<0.01),and the moderating role of moral excuses was not significant.This study will be conducive to the better implementation of the action of clearing cyberspace and to the regulation of public behaviour in cyberspace. 展开更多
关键词 ANONYMITY online socialization online transgressions moral excuses moderating effects
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Chronostratigraphy and Stratigraphic Classification of the Cretaceous of the Songliao Basin 被引量:4
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作者 Wang Pujun Du Xiaodi Wang Jun and Wang Dongpo 1)Geoenergy Department, Changchun University of Earth Sciences, Changchun, Jilin 2)Earth Sciences Department,Nanjing University,Nanjing,Jiangsu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1996年第2期207-217,共11页
Isotopic ages of synsedimentary clay minerals were directly determined with the ultrasonicscattering-settlement separation-K-Ar dilution technique. The apparent age of black mudstoneis 123 Ma for the Quantou Formation... Isotopic ages of synsedimentary clay minerals were directly determined with the ultrasonicscattering-settlement separation-K-Ar dilution technique. The apparent age of black mudstoneis 123 Ma for the Quantou Formation, 111.9-89.0 Ma for the Qingshankou Formation and77.6-76.8 Ma for the upper part of the Nenjiang Formation. The Rb-Sr isochrone age of themuddy limestone-mudstone sequence of the lower part of the Nenjiang Formation is 81 Ma andthat of the muddy evaporite of the middle part of the Quantou Formation is 122.2 Ma. On thebasis of the above isotopic ages, the authors propose a modified scheme of stratigraphic classifi-cation of the Cretaceous of the Songliao basin. 展开更多
关键词 Songliao basin CRETACEOUS lake transgressive depositional sequence isotopic age stratigraphic classification
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Sedimentary Evolution and Transgressions of the Western Subei Basin in Eastern China since the Late Pliocene 被引量:7
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作者 CHENG Yu LI Xiangqian +6 位作者 SHU Junwu BAI Shibiao ZHAO Zengyu ZHANG Xiangyun GUO Gang ZHANG Ping LIN Jingxing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第1期155-166,共12页
Sedimentary sequences in the Subei Basin are complex and have been affected by interactions between the ocean and rivers since the Late Pliocene, including the Yellow River, Huaihe River, and the Yangtze River. This s... Sedimentary sequences in the Subei Basin are complex and have been affected by interactions between the ocean and rivers since the Late Pliocene, including the Yellow River, Huaihe River, and the Yangtze River. This sedimentary evolution, in particular the timing of Pleistocene transgressions, has long been a matter of controversy owing to the lack of precise chronological evidence. The aim of this study is to explore the evolution of the sedimentary environment throughout the past 3.00 Ma in this region on the basis of a comprehensive analysis of particle size and foraminifera and ostracods collected in the TZK9 core from the Subei Basin combined with geochronological studies of magnetostratigraphy, AMS^(14)C and optically stimulated luminescence(OSL). The results show that fluvial facies in the sedimentary environment from 3.00 to 1.01 Ma. There were fluvial facies and reflects six sea-level high stands from 1.01 to 0.25 Ma. The study area was affected by four large-scale transgressions since 0.25 Ma. The four marine sedimentary layers known as DU7(buried at 48–52 m), DU5(buried at 35–41 m), DU3(buried at 16–23 m), and DU1(buried at 2–4 m) are recorded in the MIS7(210–250 ka), MIS5, MIS3, and Holocene, respectively. The magnitude of the DU5 transgression was identical to that of the DU3 transgression, both were larger than the DU7 transgression, and the DU1 transgression was the weakest. The variation of transgression strength reflects the influence of global changes in sea level, tectonic subsidence, shell ridges, and sand dams. In the TZK9 core, we found evidence of seven sea-level high stands from the Early–Middle Pleistocene, and the first one caused by regional rapid subsidence and could be traced back to 0.83-0.84 Ma. The sea-level high stands and the age of the first one recorded above was different from other cores in eastern China, this was caused by the lack of absolute age control and the differences in paleotopography during this period. This study reconstructs sedimentary evolution, determines the transgression and its age, establishes the chronology since the Late Pliocene, and provides a scientific framework for further paleoenvironmental and tectonic studies. The results of this study highlight the important role that local tectonics and global sea level play in the sedimentary evolution and transgressions that have occurred in the western Subei Basin. 展开更多
关键词 FORAMINIFERA and OSTRACODS SEA-LEVEL change TRANSGRESSION Subei Basin
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Cretaceous source rocks and associated oil and gas resources in the world and China: A review 被引量:5
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作者 Yang Ruofei Wang Yuce Cao Jian 《Petroleum Science》 SCIE CAS CSCD 2014年第3期331-345,共15页
The Cretaceous is one of the most important stratigraphic intervals for hydrocarbon source rocks. This article summarizes the distribution, formation, and development characteristics of Cretaceous source rocks and ass... The Cretaceous is one of the most important stratigraphic intervals for hydrocarbon source rocks. This article summarizes the distribution, formation, and development characteristics of Cretaceous source rocks and associated oil and gas resources in the world and China, aiming at improving the understanding of this hydrocarbon enrichment and at broadening domestic exploration. Outside China, these rocks are generally formed in marine or transgressive environments during both the Upper and Lower Cretaceous. The majority of Cretaceous source rocks are located in the Persian Gulf, Mediterranean, and Gulf Coast of the USA. Kerogen types within these source rocks have distinct spatial distribution characteristics, with high-latitude Boreal Realm, Tethyan Realm and South Gondwana Realm source rocks containing type III, II, II-III kerogens, respectively. Cretaceous source rocks in China can be mainly divided into four zones: Eastern, Central, Northwest, and Qinghai-Tibet Plateau zones. The majority of Chinese source rocks formed in the Early Cretaceous, whereas the most productive source rocks are developed in the Upper Cretaceous, such as those within the Songliao Basin. Most of these basins are formed in lacustrine environments, although some may have been influenced by transgressive events: Cretaceous source rocks are formed in four distinctive ways: 1) during Oceanic Anoxic Events and associated global sea-level rises, 2) in Black Sea-type retention basins, 3) during transgression and 4) during periods of significant terrestrial input. Formation of these source rocks is controlled by four factors: paleoclimate, paleotopography, transgression, and Oceanic Anoxic Events. These four major controlling factors indicate that China's hydrocarbon exploration within the Cretaceous should focus on two key areas with extremely low exploration levels, the Qinghai-Tibet Plateau and the southeastern coast of China. 展开更多
关键词 CRETACEOUS source rock organic matter TETHYS TRANSGRESSION
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Recognition of Milankovitch Cycles in the Natural Gamma—Ray Logging of Upper Cretaceous Terrestrial Strata in the Songliao Basin 被引量:6
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作者 WU Huaichun ZHANG Shihong +1 位作者 SUI Suwen HUANG Qinghua 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第6期996-1001,共6页
Spectrogram analysis of seven natural gamma-ray logging of Member 1 of the Qingshankou Formation (K2qn^1) and Member 1 and 2 of the Nenjiang Formation (K2n^1-2) of Late Cretaceous age in the Songliao Basin reveals... Spectrogram analysis of seven natural gamma-ray logging of Member 1 of the Qingshankou Formation (K2qn^1) and Member 1 and 2 of the Nenjiang Formation (K2n^1-2) of Late Cretaceous age in the Songliao Basin reveals sedimentary cyclicities controlled by Milankovitch climate periodicities. The recognition of Milankovitch cycles allows estimation of an average accumulation rate of ~7.55- 8.62 cm/ka for the K2qn^1 sections, and ~6.69-10.16 cm/ka for the K2n^1-2 sections. Two marine transgression events occurred during the deposition of K2qn^1 and K2n^1-2 and their ages are at ~0.74- 1.10 Ma and ~2.38-4.84 Ma, respectively. Identification of Milankoviteh cycles from fine-grained deep lake sedimentary rocks in the Songliao Basin may provide great potential for high-resolution stratigraphic subdivisions and correlations. 展开更多
关键词 Songliao Basin gamma-ray logging Milankovitch cycles marine transgression events
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The Age of the Old Transgression Sequence in the Pearl River Delta, China 被引量:5
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作者 YU Zhangxin ZHANG Ke +2 位作者 LI Xiaoyang LIANG Hao LI Zhongyun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第4期1515-1516,共2页
The Pearl River Delta (PRD) is located in the north coast area of the South China Sea (SCS). As one of the largest delta in China, only the two latest events among the several tens of eustatic fluctuations occurri... The Pearl River Delta (PRD) is located in the north coast area of the South China Sea (SCS). As one of the largest delta in China, only the two latest events among the several tens of eustatic fluctuations occurring in the Quaternary were recorded in almost whole area of the PRD. 展开更多
关键词 The Age of the Old Transgression Sequence in the Pearl River Delta China OSL PRD SCS
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Dynamic simulations of the late MIS 3 transgressions in the East China Sea and southern Yellow Sea,China 被引量:2
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作者 YE Liangtao YU Ge +1 位作者 LIAO Mengna LI Yongfei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第10期48-55,共8页
Abundant evidences of higher sea levels from Jiangsu and Fujian coasts have proved a marine transgression event during 30–40 ka BP, suggesting that there was a stage with high sea level and a warm climate when ice sh... Abundant evidences of higher sea levels from Jiangsu and Fujian coasts have proved a marine transgression event during 30–40 ka BP, suggesting that there was a stage with high sea level and a warm climate when ice sheets shrank in the Northern Hemisphere. The duration of 30–40 ka BP spanned a period in the late Marine Isotope Stage 3(MIS 3) and was in nature an interstadial epoch during the Last Glacial period of the Quaternary. Different from the glacial period with a cold climate, this marine transgression considered as a penultimate higher sea level during the Quaternary remains a puzzle that why the evidence is contrary to the Quaternary glacial theory. It is important to understand sea level rise for these areas sensitively responding to the global changes in the future. To recognize the key issues on sea level changes, the eustatic sea level(H_S) was defined as the glaciation-climateforced sea levels, and the relative sea level change(H_R) was defined as that a sea level record was preserved in sediment that experienced multiple secondary actions of land and sea effects. On the basis as defined above, we constructed multi-level models of climate-driven glacio-eustatic changes and land-sea systems. By integrating data sets from eight borehole cores and prescribing the boundary conditions, we simulated the changes of HS and HR in the East China Sea and southern Yellow Sea areas in the late MIS 3. The marine transgression strata from the borehole core data was identified at ca. 30 m below present sea level as a result of the collective influence of ice melting water, neotectonic subsidence, sediment compaction and terrestrial sediment filling since ca. 35 ka ago,whereas the simulated relative sea-levels turned out to be –26.3––29.9 m a.s.l. The small error involved in the simulation results of ±(2.5–4.5) m demonstrated the credibility of the results. Our results indicated that sea level change in the late MIS 3 was dominated by glacial effects, in which the eustatic sea-level was between –19.2––22.1m a.s.l. The study sheds light on the nature of sea-level changes along the east coast of China in the late MIS 3 and contributes to understanding the characteristics of marine transgression under the effects of multiple complex land-sea interactions. 展开更多
关键词 marine transgression late MIS 3 dynamic simulation sea level change
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Assessment of genetic effects on important breeding traits in reciprocal DH populations of winter oilseed rape (Brassica napus L.) 被引量:1
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作者 Laurencja Szala Teresa Cegielska-Taras +1 位作者 Elzbieta Adamska Zygmunt Kaczmarek 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第1期76-85,共10页
Here we present a study on the genetic effects of agronomic and seed quality traits in double haploid (DH) populations, which were developed by microspore culture from reciprocal F1 hybrids produced between cultivar... Here we present a study on the genetic effects of agronomic and seed quality traits in double haploid (DH) populations, which were developed by microspore culture from reciprocal F1 hybrids produced between cultivar Californium and DH W-15. Each of the populations consisted of 25 DH lines. The field experiments were conducted in a randomized complete block design with three replications during three growing seasons. Field observations were recorded on seed yield and its structure: the number of branches and pods per plant, the number of seeds per pod, the 1 000-seed weight, the content of fat in the seeds, and three unsaturated fatty acids (oleic, linoleic, linolenic) in the seed oil. In order to investigate the influence of cross direction on the studied traits, parental effects were evaluated on the basis of differences between reciprocal DH populations. The maternal effect was revealed on the number of seeds per pod and the effect of the paternal form on linolenic acid content. The occurrence of transgression effects also depended on the direction of crossing and this was particularly noticeable in terms of the number of seeds per pod. The use of multivariate statistical methods allowed for the simultaneous characterization and grouping of tested lines in terms of several traits. Graphic images of the distribution of DH lines in the space of the two first canonical variates showed a great variation between the two reciprocal populations, both in terms of yield and its components, as well as fat and those unsaturated fatty acids. 展开更多
关键词 DH line reciprocal cross oilseed rape multivariate analysis TRANSGRESSION
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The brackish-water bivalve Waagenoperna from the Lower Jurassic Badaowan Formation of the Junggar Basin and its palaeoenvironmental and palaeogeographic significance 被引量:1
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作者 Yanhong Pan Jingeng Sha +4 位作者 Yaqiong Wang Xiaolin Zhang Xiaogang Yao Bo Peng Xin Rao 《Geoscience Frontiers》 SCIE CAS CSCD 2013年第1期95-103,共9页
The brackish-water bivalve Waagenoperna Tokuyama, 1959 is reported from the Lower Jurassic Badaowan Formation at four localities, along the southern margin and western margin of the Junggar Basin. Taphonomic features ... The brackish-water bivalve Waagenoperna Tokuyama, 1959 is reported from the Lower Jurassic Badaowan Formation at four localities, along the southern margin and western margin of the Junggar Basin. Taphonomic features recorded in the field indicate that it occurs in autochthonous or parautochthonous assemblages. The autecology of Waagenoperna therefore yields information on the palaeoenvironment of the area. The restriction of Waagenoperna to marine and brackish-water settings suggests that the sea water once reached these areas during the Sinemurian. This paper discusses the palaeogeographic implications and suggests an ingression of the sea water from the west to the western and southern part of the Junggar Basin. Additionally, the two Waagenoperna species collected from the Haojiagou section in the Junggar Basin are taxonomically documented. 展开更多
关键词 Brackish-water bivalve Waagenoperna Transgression Sinemurian Junggar Basin
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Holocene Biostratigraphic Zones Corresponding Litho-Chronostratigraphy, Environment of Deposition and Successive Changes in the Geomorphology of Bengal Basin, India during Last 10,000 Years 被引量:1
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作者 Prasanta Kumar Sen Manju Banerjee 《International Journal of Geosciences》 2016年第4期615-629,共15页
Biostratigraphic Zones Bb. Bz. H. I-V distinguished in C<sup>14</sup> dated Peat, peaty clay sediments above arid, Barren zone have identified distinct environment of deposition as fresh water mixed b... Biostratigraphic Zones Bb. Bz. H. I-V distinguished in C<sup>14</sup> dated Peat, peaty clay sediments above arid, Barren zone have identified distinct environment of deposition as fresh water mixed brackish water to shallow marine to brackish water mangrove swamp, brackish water mixed fresh water swamp followed by colonization of non-littoral species to fresh water swamp during Holocene in the Bengal basin, India in chronological succession. The successive phases of depositional environment have identified the events of sea level rise, marine transgression and sea ward movement of the sea. The unique database has explored successive changes in the geomorphology of South Bengal from upland dry to marine deltaic environment to fresh water upland condition. 展开更多
关键词 HOLOCENE BIOSTRATIGRAPHY Flandrian Transgression GEOMORPHOLOGY Bengal Basin
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Late Cretaceous Paleoenvironment and Paleoclimate Change During Large Lake Transgression in the Songliao Basin,NE China
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作者 Dangpeng Xi,Shun Li,Xia Jing,Jing Zhao,Xiaoqiao Wan China University of Geosciences(Beijing),Beijing 100083,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期123-123,共1页
Late Cretaceous lacustrine deposits in Songliao Basin provide a unique material to study the paleo-environment and paleoclimate of nomarine Cretaceous.Two large transgressions occurred during the Qingshankou and Nenji... Late Cretaceous lacustrine deposits in Songliao Basin provide a unique material to study the paleo-environment and paleoclimate of nomarine Cretaceous.Two large transgressions occurred during the Qingshankou and Nenjiang deposition times,the later of which was larger.Based on sedimentation,ostracode,TOC,HI,δ<sup>13</sup>C<sub>org</sub> and C/N from upper Yaojia Formation to Lower Nenjiang Formation in the eastern Songliao Basin。 展开更多
关键词 Cretaceous Songliao Basin PALEO-ENVIRONMENT PALEOCLIMATE LAKE TRANSGRESSION
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RECENT ADVANCES IN GEOLOGICAL RESEARCH IN PARTS OF LESSER AND TETHYS HIMALAYA OF INDIA, SOUTH OF TIBETAN PLATEAU (KUMAON, GARHWAL AND ARUNACHAL PRADESH)
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作者 Vinod C. Tewari(Wadia Institute of Himalayan Geology, Dehra Dun, 248001, India) 《地学前缘》 EI CAS CSCD 2000年第S1期66-66,共1页
Recent advances in geological, palaeobiological and stable isotopic research in Kumaon\|Garhwal Lesser and Tethys Himalaya suggest that India was part of a major single super continent Rodinia during Neoproterozoic—L... Recent advances in geological, palaeobiological and stable isotopic research in Kumaon\|Garhwal Lesser and Tethys Himalaya suggest that India was part of a major single super continent Rodinia during Neoproterozoic—Lower Palaeozoic times. The breakup of Rodinia and fragmentation of Gondwana land, existence of large Proto\|Tethys ocean, low latitude glaciation and global warming reflected by carbon isotopes and imprints of Pan African rifting events have been recently recorded in the Indian Himalaya, South of Tibetan Plateau (Tewari, 1998). A detailed correlation of these events in other parts of the NW and NE Himalaya and China further supports that these events are of global significance.The complete sequence of Lower Palaeozoic is missing in the Lesser Himalaya after regression of sea in the Lower Cambrian, however three major marine transgressions during Permian, Cretaceous and Eocene have been recorded over Terminal Proterozoic/Cambrian sequences. The discovery of microstromatolites and microbiota from the Menga (Buxa) dolomite of eastern Himalaya, Arunachal Pradesh (Tewari, 1999) also confirm Terminal Proterozoic age and sedimentation. The Permian marine transgression throughout the Himalaya suggest birth of Neotethys sea.Shallow marine reef builders, cyanobacteria\|bacteria and stromatolites of Early Carboniferous age were thriving in the Himalayan Tethys of India. 13 C records from Lesser and Tethys Himalaya reflect global isotopic variations in Neoproterozoic to Palaeozoic oceans of the world. 展开更多
关键词 RODINIA Lower PALAEOZOIC TRANSGRESSION microstromatolite MICROBIOTA 13 C RECORDS
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Characteristics and Dolomitization of Dolostones in Nenjiang Formation Unit 1,Northern Songliao Basin
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作者 Yuan Gao China University of Geosciences(Beijing),Beijing 100083,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期99-99,共1页
Songliao Basin is a large-scale Cretaceous continental sedimentary basin in northeastern China. In the northern Songliao Basin Nenjiang Formation Unit 1 are mainly dark mudstones with dolostone interbeds.Understanding... Songliao Basin is a large-scale Cretaceous continental sedimentary basin in northeastern China. In the northern Songliao Basin Nenjiang Formation Unit 1 are mainly dark mudstones with dolostone interbeds.Understanding the sedimentary characteristics and dolomitization of the dolostones is of great significance to the paleoenvironment and paleoc- 展开更多
关键词 Songliao Basin Nenjiang Formation DOLOMITE SEDIMENTARY CHARACTERISTICS REPLACEMENT marine TRANSGRESSION
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Transgressions and the sea-level changes of the western Taiwan Strait since the Late Pleistocene
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作者 Lan Dongzhao, Zhang Weilin, Chen Chenghui, Xie Zaituan, Yu Yongfen and Cai Feng Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1993年第4期617-627,共11页
The sedimentary sequences since the Late Pleistocene can be divided into Layers E, D, C, B, A from old to young according to systematic analysis of grain-size, pollen and spore, diatom, foraminifera, radiocarbon datin... The sedimentary sequences since the Late Pleistocene can be divided into Layers E, D, C, B, A from old to young according to systematic analysis of grain-size, pollen and spore, diatom, foraminifera, radiocarbon dating and paleogeomagnetism of 16 sedimentary cores from the sea area of the western Taiwan Strait. The results proved the existences of the Langqi transgression (upper section of Layer D) formed in middle and late stages of early Wurm glacial period, Fuzhou transgression (Layer C) formed in Wurm sub-interglacial period and Changle transgression (Layer A) formed in postglacial period. It was also the first time to discover the Jinmen transgression (Layer E) formed in Riss -Wurm interglacial period. In this paper it is proposed that most part of the Taiwan Strait emerged as land in the early stage of early Wurm glacial period, and was still under sublittoral environment in late Wurm glacial period, as well as the existence of Dongshan Continental Bridge was in 8×103 a BP. 展开更多
关键词 Taiwan Strait sedimentary sequence TRANSGRESSION sea-level change
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