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1.
Since a 1921 law the harnessing of the Rhône River from Lyon to the Mediterranean has been directed by a national company composed of the public sector (fromthe valley) as well as of various consumers or distributors of current such as the SNCF or the EDF. This company, the National Company of the Rhône (CNR), was a precursor to the establishment of the TVA in the United States, although it did not begin operations until aftetr the TVA due to prolonged technical negotiations and to the difficulties involved in locating financial support in a period of economic crisis. Even though the utilization of hydraulic power constitutes the prime aim of the CNR, it has also focused on navigation, irration and other agricultural uses from the outset.This article will not further discuss the hydro-electric stations on the Rhône which usually supply more than 22% of French hydro-electric output from thirteen stations now in operation (total power is 2,350 MW and annual average output is 13,000 GWh). This paper will treat the question of the nature and importance of the side effects of the harnessing of the Rhône apart from its essential energy function.  相似文献   

2.
Doklady Earth Sciences -  相似文献   

3.
Doklady Earth Sciences - A complex of works including geomorphological deciphering, field survey, drilling, electric prospecting, and dating of deposits using the radiocarbon method and optically...  相似文献   

4.
The littoral fringe ranging between the capes of Bizerte and Ras Ettarf (north-eastern of Tunisia) represents an unstable and complex system of the Tunisian littoral. The instability of this zone is dependent, on one hand, on natural phenomena contributing to the destabilization of certain sectors to which are added the induced effects of anthropic factors on the other hand. This study was carried out from grain size analysis and a simulation of swell plans. This led the authors to highlight the increasing grain size classification from the zones of the Capes towards the sandy low coasts and to quantify the moved volumes under the effect of the dominant swells in order to simulate the fattening and erosion zones in this sector. A littoral transit of direction north–south is able to transport 45,000 m3/year of sediment which are participating in the fattening of the beach of Sidi Salem; 6,000 m3/year of sandy sediments are directed towards the beach of R'mel and 12,000 m3/year are participating in the fattening of the beaches of Chatt Mami (Ras Jebel) and Lahmmari (Raf Raf).  相似文献   

5.
A scheme of radiolarian zonal subdivision is proposed for the upper Albian–Santonian of the Tethyan regions of Eurasia. The upper Albian contains one zone: Crolanium triangulare; the Cenomanian contains three zones: Patellula spica (lower Cenomanian), Pseudoaulophacus lenticulatus (middle Cenomanian), and Triactoma parva (upper Cenomanian); the Turonian contains four zones: Acanthocircus tympanum (lower Turonian (with no upper part)), Patellula selbukhraensis (upper part of the lower Turonian), Phaseliforma turovi (middle Turonian (with no upper part)), and Actinomma (?) belbekense (upper part of the middle Turonian–upper Turonian); the Coniacian contains two zones: Alievium praegallowayi (lower part of the Coniacian) and Cyprodictyomitra longa (upper part of the Coniacian); the Santonian contains three zones: Theocampe urna (lower Santonian), Crucella robusta (middle Santonian–lower part of the upper(?) Santonian), and Afens perapediensis (upper part of the upper Santonian). The biostratigraphic subdivisions are correlated with biostrata in the schemes proposed previously for the Tethys and Pacific. A new species Patellula selbukhraensis Bragina sp. nov. is described.  相似文献   

6.
Yangtzeconus priscus-Archaeospira ornata, an important earliest Cambrian benthonic Assemblage of the Yangtze micromolluscan fauna, occurs mainly in the Lower Cambrian Zhongyicun and Dahai Members of the Yuhucun Formation in E Yunnan, the Tianzhushan Member （=Huangshandong Member） of the Dengying Formation in W Hubei and the Maidiping Member of the Hungchunping Formation in C Sichuan, China. About 90% of the genera of this Assemblage are unknown from the Nemakit-Daldynian and Tommotian molluscan Assemblages of the Siberian Platform, Russia. About 90% of the Siberian molluscan genera do not occur in the Zhongyicun and Dahai Members in the Meishucun section and in the corresponding beds of the Yangtze Platform, because the Tommotian molluscan Assemblage is characterizedly abundant archaeocyathids. It is clearly indicated that the Yangtze and Siberian molluscan Assemblages represent different bio- and lithofacies and ages. The age of the pre-trilobitic Yangtzeconus priscus-Archaeospira ornata Assemblage is older than that of the Nemakit-Daldynian and Tommotian molluscan Assemblages and referable to the Earliest Cambrian. Two new genera Mcnamaraconus and Zhangwentangoconus are herein proposed.  相似文献   

7.
Comparative analysis of the composition and formation conditions of the dunite–pyroxenite association of the Guli Pluton and ultramafic vulcanite (meimechite) showed the similarity of their initial melts and the same type of crystallization, demonstrating the cumulative origin of dunite.  相似文献   

8.
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9.
Doklady Earth Sciences - A first set of K–Ar isotopic ages obtained, which allowed to estimate the age of the largest volcanoes of the Anaunsky Dol (3.2, 2.2 and 1.9 Ma) and eruptive centers...  相似文献   

10.
A spore-pollen assemblage was established for the first time in the sediments of the Malokuril??skaya Formation (Khromova Bay, Shikotan Island, Lesser Kuril Range, Kuril island arc system). This find enabled dating of the sediments of the uppermost part of the Malokuril??skaya Formation, which, based on this data, are referred to the Maastrichtian-Danian boundary. The assemblage of radiolarian species was identified for the entire section of the Malokuril??skaya Formation. In sediments of the lower part of the section, members of the Inoceramus group were described. These findings add new information to the paleontological characteristics of the Malokuril??skaya Formation. Moreover, our work allowed detailed correlation of the palynological assemblage studied with coeval palynological assemblages of adjacent areas. The similarity of Cretaceous-Paleogene sections of the Ust-Palanskaya (West Kamchatka), Uchir (Sakhalin Island) and Malokuril??skaya Formations, the Upper Cretaceous basement and the Cenozoic cover of the underwater Vityaz Ridge support the shared history of the development of the entire transition zone from the marginal Sea of Okhotsk to the Pacific at the Maastrichtian-Danian boundary.  相似文献   

11.
The paper presents the results of detailed paleomagnetic studies of the Paleogene-Neogene continental sediments stripped by borehole 8 in southwestern West Siberia (Russkaya Polyana district, Omsk Region), near the Kazakhstan frontier. According to the previous biostratigraphic data, the sediments under study formed from Rupelian to Ruscinian. The results of stepwise thermal demagnetization and alternating-field demagnetization were used to carry out a component analysis of natural remanent magnetization, which revealed characteristic (primary) remanent magnetization (ChRM). The compiled paleomagnetic section, which includes seven regional horizons and same-named formations (Oligocene Atlym, Novomikhailovka, and Zhuravka Formations and Neogene Abrosimovka, Beshcheul, Tavolzhan, and Novaya Stanitsa Formations), was compared with the Cenozoic polarity scale for the West Siberian Plate. This made it possible to assess the completeness of the geologic section of the Paleogene and Neogene continental sediments in borehole 8 and to record the magnetozones and their fragments missing from the magnetostratigraphic section (for some intervals, in absolute chronology). The comparison shows that the magnetostratigraphic section of the studied sediments at the edges of the Om’ basin is approximately twice shorter than that of the basin center.  相似文献   

12.
The U–Pb (LA–ICP–MS) age of detrital zircons from the Upper Cambrian–Lower Ordovician terrigenous rocks of the Baidarata Allochthon, which is located in the northern part of the Polar Urals, is determined. The analysis of the youngest zircon population indicates a broad occurrence of the Uralides in this area rather than Pre-Uralides, as was considered previously. The Bedamel island-arc rocks (rather than Timan orogen) were probably the major provenance for the studied sequences. The results of statistical processing of the U–Pb ages of zircons from coeval rocks of Arctic regions suggest similar provenances for the Baidarata Allochthon and Novaya Zemlya and Severnaya Zemlya archipelagoes.  相似文献   

13.
The results of bio- and lithostratigraphic studies of the Givetian-Frasnian rocks in the Tsil’ma River basin are reported. They suggest regularities in sedimentation: distinct rhythmicity and similar succession in the structure of formations. We have identified five palynocomplexes that characterize the formations and make it possible to accomplish a confident biostratigraphic subdivision of sections. Their correlation with coeval complexes in the adjacent areas has been accomplished. The results made it possible to unravel specific features of miospore assemblages formed in the continental and coastal-marine facies.  相似文献   

14.
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15.
Doklady Earth Sciences - The first results of the geochronological dating of the specific sill-like gabbrodiorite–granodiorite intrusive bodies within the areal extent of the Paleoproterozoic...  相似文献   

16.
The study of ammonites from the upper part of the upper Bajocian and lower part of the lower Bathonian in the sections of the basin of the Bolshoi Zelenchuk (Karachay-Cherkessia) allowed the recognition of Beds with Parkinsonia djanelidzei (approximate equivalent of the middle part of the Parkinsonia parkinsoni Chronozone) and Beds with Oraniceras scythicum (lower part of the Zigzagiceras zigzag Chronozone). The taxonomic composition and distribution of foraminifers, ostracodes, dinoflagellate cysts, and miospores were studied in the samples from these deposits (upper part of the upper member of Djangura Formation). The recognized characteristic assemblages of microfauna and palynomorphs allowed ostracode and dinocyst subdivisions to be proposed for the Bajocian–Bathonian boundary beds of the Northern Caucasus for the first time. The most important taxa, including ammonites, foraminifers, ostracodes, and dinocysts, are illustrated.  相似文献   

17.
Doklady Earth Sciences - Data indicating the important role of microorganisms in the redistribution of REEs in the weathering crust and the decisive role in the concentration of REEs during the...  相似文献   

18.
Doklady Earth Sciences - This paper reports on the first U–Pb dating of zircons from dacites of the volcanic paleo-edifice of the andesite–dacite complex of the Eastern Zone of the...  相似文献   

19.
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20.
Doklady Earth Sciences - Thermodynamic calculations on the impact of carbonate–bicarbonate fluids cooling from 500 to 100°C on a monazite + calcite association with a simultaneous...  相似文献   

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