Interrelation between QBO and 11-year solar cycle effects in total column ozone over Europe     

Sergei A. Sitnov 《Climate Dynamics》2009,33(5):591-602

On the basis of total column ozone (TO) data obtained in the period of 1957–2007 at 10 ground-based European stations, characterized by long and highly reliable measurements, the effects of the quasi-biennial oscillation (QBO) and 11-year solar cycle (11-year SC), manifesting in TO are investigated. The results of comparative analysis of seasonal differences between different QBO/solar extremes convincingly demonstrate interrelation between the QBO and 11-year SC effects. It is shown that solar activity modulates the phase of the QBO effect so that the quasi-biennial TO signals during solar maximum and solar minimum are nearly in opposite phase. It is also demonstrated that isolated under permanent conditions of solar minimum or solar maximum the QBO effects in TO have the time scale of about 20 months. Solar modulation of the QBO effect makes the QBO a conductor of the solar cycle impact on TO over Europe. The mechanism of influence of the 11-year SC on the QBO and probably includes its impact on the QBO amplitude in the equatorial lower stratosphere, mainly through weakening of the equatorial easterlies during solar maximum.  相似文献   

Geochronology and paleomagnetism of mafic igneous rocks in the Olenek Uplift, northern Siberia: Implications for Mesoproterozoic supercontinents and paleogeography     

Michael T.D. Wingate  Sergei A. Pisarevsky  Dmitry P. Gladkochub  Tatiana V. Donskaya  Konstantine M. Konstantinov  Anatoly M. Mazukabzov  Arkady M. Stanevich 《Precambrian Research》2009,170(3-4):256-266

We present a new, reliably dated Mesoproterozoic paleopole for Siberia, based on a combined geochronological and paleomagnetic study of mafic rocks within the Mesoproterozoic Sololi Group of the Olenek Uplift in northern Siberia. Ion microprobe (SHRIMP) U–Pb analysis yields crystallisation ages of 2036 ± 11 Ma for zircon from a basement granite and 1473 ± 24 Ma for baddeleyite from a large dolerite sill within the Kyutingde Formation. The baddeleyite result indicates that the lower Sololi Group is significantly older than was suggested by previous K–Ar results. Paleomagnetic analysis of the dolerite sill and related mafic intrusive rocks yields a paleopole at 33.6°N, 253.1°E, A₉₅ = 10.4°. A positive baked-contact test between the Kyutingde sill and sedimentary country rocks shows that the magnetisation is primary. Comparison of this paleopole with coeval results for Laurentia provides a revised reconstruction between Siberia and Laurentia, and implies that these two continents were parts of a single Mesoproterozoic supercontinent since at least 1473 Ma. We argue that Siberia, Laurentia, and Baltica belonged to the same supercontinent between 1473 Ma and mid-Neoproterozoic time.  相似文献   

Ultrastructures of stromatolites from the Wenlockian of Chernov Swell     

V. A. Matveev 《Doklady Earth Sciences》2017,474(1):494-497

The morphology of fossilized biogenic particles and the elemental composition of biogenic formations, discovered for the first time in Lower Silurian deposits within the Timan–Northern Urals region, are considered. The diversity of biogenic formations identified in stromatolites indicates a high level of activity of microorganisms forming the cyanobacterial mat and confirms the microbial origin of the Wenlockian stromatolite buildups.  相似文献   

Geometrical considerations in imaging the solar corona     

David Alexander  Sergei Katsev 《Solar physics》1996,167(1-2):153-166

X-ray observations of the solar corona show that it is comprised of three-dimensional magnetic structures which appear to be primarily in the form of fluxtubes or loops. Imaging the X-ray corona has led to a greater understanding of the dynamical behaviour of and the energy distribution in these magnetic structures. However, imaging observations, by their very nature, integrate along the line of sight resulting in a two-dimensional representation of the actual three-dimensional distribution. The optically thin nature of the solar corona to X-ray radiation makes the integrated images particularly difficult to interpret. The analysis of the two-dimensional observations must, therefore, inlcude the effect of the orientation of the coronal structure to the line-of-sight direction; a fact which is almost always ignored. In this paper we discuss the effect of loop orientation on the two-dimensional representation and argue that these effects may lead to a misinterpretation of the physics occurring in the structures observed. In particular, we discuss observations taken by the Soft X-ray Telescope (SXT) on board the Yohkoh satellite, taking account of the instrumental thermal response, spatial resolution, and point-spread-function.We test the effect of geometry on the determination of the loop pressure by considering equatorial loops at various longitudes and discuss the implications of this for studies of coronal soft X-ray loops.  相似文献   

Diagnostics of the Internal Structure of Stars using the Differential Response Technique     

Ian Roxburgh  Sergei Vorontsov 《Astrophysics and Space Science》2003,284(1):187-191

We address the problem of the diagnosing the deep interior structure of stars using acoustic p-modes, and investigate the diagnostic capabilities of two complementary approaches both based on the differential response technique (Vorontsov, 1998): (a) direct calibration using a grid of evolutionary stellar models, and (b) linear and non-linear (with consecutive linearisations) inversion of low-degree frequencies. We apply this analysis to the frequencies of a model of an old 0.8M star, and to the solar frequencies obtained from BiSON measurements, using a 2-D grid of reference models of different mass and age. We explore the convergence and stability of the asteroseismic inversion, performed with the adaptive regularisation technique of Strakhov and Vorontsov (2001).  相似文献   

Cretaceous radiolarian fauna from the Kiselyovsky subterrane, the youngest accretionary complex of the Russian continental far east: Paleotectonic and paleogeographic implications     

Sergei V.  Zyabrev 《Island Arc》1996,5(2):140-155

Abstract The Kiselyovsky subterrane is the northeastern section of the Kiselyovsko-Manominsky terrane, a distinguishable tectonic unit in the north of the Sikhote-Alin Range. The terrane has been treated as part of the accretionary wedge belonging to the Khingan-Okhotsk active continental margin, but its structure and stratigraphy have been poorly understood. This paper presents new data on the subterrane structure, lithology and radiolarian biostratigraphy. The following lithostratigraphic units are established in the terrane: a ribbon chert unit, a siliceous mudstone unit and a elastics unit. Abundant Valanginian to late Hauterivian-early Barremian radiolarian assemblages are obtained from the upper part of the chert unit in addition to the known Jurassic radiolarians. The radiolarian age of the lower part of the siliceous mudstone unit (red siliceous mudstone) is determined as early Hauterivian-early Aptian. The unit's upper part (greenish-gray siliceous mudstone and dark-gray silicified mudstone) and the clastics unit contain Albian-Cenomanian assemblages. The arrangement of the units is treated as a chert-elastics sequence, whose vertical lithologic variations indicate environmental changes from a remote ocean to a convergent margin, reflecting an oceanic plate motion towards a subduction zone. The subterrane structure is a stack of imbricated slabs composed of various lithostratigraphic units, and is complicated by folding. The structure's origin is related to subduction-accretion, which occurred in the Albian-Cenomanian. The data presented provide a unique basis for accretionary wedge terranes correlation in the circum-Japan Sea Region, and the Kiselyovsky subterrane is correlated in this study with the synchronous parts of the East Sakhalin, Hidaka and Shimanto terranes. The Albian-Cenomanian radiolarian assemblages were deposited in the Boreal realm, while Valanginian ones are Tethyan; this indicates a long oceanic plate travelling to the north. The former assemblages contain an admixture of older species, redeposited by bottom traction currents and turbidite flows in trench environments.  相似文献   

沉积盆地学说的发展及主要的含油气盆地分类   总被引：3，自引：0，他引：3  

王骏鸟.  СА 《世界地质》1996,15(2):75-80

从科学史观出发，介绍了含油气盆地概念及其学说的发展。展示主要的盆地分类方案，论述含油气盆地分类研究在盆的含油气性评价中所具有的重要意义。指出盆地分类研究的发展方向和未来分类方案所应具有的特点。  相似文献   

西伯利亚克拉通寒武纪沉积史:碳酸盐台地和盆地的演化   总被引：2，自引：0，他引：2  

Sergei S. Sukhov 《沉积与特提斯地质》1997,17(5):27-39

西伯利亚克拉通或古西伯利亚台地，其面积４００００００ｋｍ２以上，是亚洲北部最主要的大陆地块之一。它以寒武系分布区域极为广泛、层序非常完整为特色。寒武系构成了遍及全区的下沉积盖层和出露在大的正向构造内。寒武纪时，研究区是重要的碳酸盐沉积区，有碳酸盐－硅质碎屑的混合沉积、蒸发盐、礁和深水盆地的碳酸盐沉积。半个多世纪来，区内进行了各种大型的旨在找烃的地质调查及有关的寒武系层理、古地理和古构造的重建，以及沉积环境的重塑。但关于沉积物内部构造的研究工作一直主要是根据传统地层学的“连续地层柱”概念。有些工作者认为，古深度和地貌史或排列的各式各样的恢复不强调瞬时。只有最近１０—１５年，地下调查配合成因地层学和盆地分析概念的发展，使得有可能将生物群演化、沉积体边界的形状和类型以及它们的成因和对各种因素（诸如以上所述各种及相对海平面变化之类）的影响综合为统一的系统。这种区域继承观点的研究方法在６０年代后期由Ｇｒａｃｈｅｖｓｋｙ（１９６９）提出，然后由Ｓａｖｉｓｔｋｙ（１９７９）和Ａｓｔａｓｈｋｉｕ（１９８４）详尽阐述，其目的是重建西伯利亚克拉通盆地充填和发展中的动力学  相似文献   

Relict back-arc basins of Eurasia and their hydrocarbon potentials     

Sergei  Aplonov Kenneth J.  Hsü Vitali  Ustritsky 《Island Arc》1992,1(1):71-77

Abstract Large petroliferous basins in the continental interior are characterized by very thick sedimentary sequences. It is suggested that these are not intracratonic basins, but areas underlain by oceanic crust. These include the Western Siberian, Pre-Caspian, South Caspian, North and South Kara Basins of the Commonwealth of Independent States, and Tarim, junggar and Qaidam Basins of China. The relict ocean basins are distinguished by their basement topography, by their magnetic signatures and by their elevated Moho. Their sedimentary history is distinguished by an abrupt subsidence, followed by isostastic subsidence under sedimentary load. Two circumstances have contributed to the genesis of giant hydrocarbon deposits in these basins: (1) the geochemical environment in those basins was at one time oxygen-deficient as they evolved from the open marine, through restricted marine to become inland alluvial basins; and (2) the sedimentary in-fill provide thick reservoir beds. Oil has accumulated in older structures, folds, faults, unconformities etc. on the margin of the basins, trapping early migrated hydrocarbons.  相似文献   

On the classical expansion of the perturbing function in individual orbital elements     

Irina Tupikova  Michael Soffel  Sergei Klioner 《Celestial Mechanics and Dynamical Astronomy》1999,74(3):147-152

Starting from the classical expansion of the perturbing function in the three‐body problem, the transformation to individual orbital elements is performed in principle up to any degree in small parameters. Some corrections to the results presented in the well‐known article by Yuasa on secular perturbations of asteroids are given. Consequences for the expansion of the indirect part of the perturbing function are discussed. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献