Delta formation processes at the Mississippi River mouth     

V. N. Mikhailov  M. V. Mikhailova 《Water Resources》2010,37(5):595-610

Specific processes of delta formation at the Mississippi River mouth are discussed. In the last 7000–8000 years, a series of large deltaic lobes was formed in succession at the Mississippi River mouth under the condition of high river sediment runoff and stabilization of the ocean level after its sudden postglacial rise. In the mid-XX century, the formation of a new deltaic lobe began at the Atchafalaya Branch mouth. Over the last centuries, the processes of delta formation at the Mississippi River mouth slowed down as a result of the river sediment runoff decrease after flow regulation of the Missouri and Arkansas tributaries; in some parts of the deltaic plain, these processes gave way to degradation of marshes and seashore erosion under the impact of intense land subsidence. The current processes of delta formation are under the great influence of local economic activities.  相似文献   

Hydrological and morphological processes in the mouth area of the Columbia River (United States) and their changes under the impact of large-scale hydroengineering works     

M. V. Mikhailova 《Water Resources》2008,35(2):137-155

The main hydrological and morphological features of the Columbia River mouth area, including its tidal estuary, are discussed. Close attention is given to the characteristics of large-scale hydraulic projects in the river basin as well as to dredging and channel training operations in the river mouth area and to the assessment of the impact of these operations on hydrological and morphological processes. Variations in the regime of river flow after its regulation, processes of dynamic interaction and mixing of river and sea water in the estuary are characterized. Changes of the mouth bar and sea coasts near the Columbia River mouth as a result of construction of stream-training jetties are discussed.  相似文献   

Features of the Atmospheric Temperature Variations Prior to Strong Earthquakes in Kamchatka and Their Relation to the Fluxes of Outgoing Infrared Radiation     

G.?A.?Mikhailova  O.?V.?Kapustina  Yu.?M.?MikhailovEmail author  S.?E.?Smirnov 《Geomagnetism and Aeronomy》2018,58(4):548-553

The temperature variations of the near-surface atmosphere in Kamchatka at Paratunka observatory and fluxes of outgoing infrared radiation prior to strong Kuril earthquakes (November 15, 2006, M = 8.3; January 13, 2007, M = 8.1) have been analyzed. It is shown that the radiation fluxes at ground level, as measured on satellites above the epicenter of earthquakes and above a remote observatory, coincide with each other, both in magnitude and in the feature of their time variations. The temperature measured directly at the observatory and the temperature at surface level estimated from satellite observations differ in magnitude, but they coincide in the feature of their time variations. The detected temperature increase (despite the negative regular trend at this time of year) is caused by the appearance of an additional heat source entering in the nearsurface atmosphere. This result, together with the studies of variations of various geophysical data before strong earthquakes performed earlier in Kamchatka, led to the conclusion that the additional heat source is in the Earth’s crust.  相似文献   

The Tekeli earthquake of 2009 in Kazakhstan: Source and effects     

N. N. Mikhailova  N. N. Poleshko 《Seismic Instruments》2011,47(2):180-190

The article investigates parametrization issues of the main shock from the earthquake of June 13, 2009, m _b = 6.3 felt in Tekeli town with intensity 7. Spatial characteristics of the source, mechanism and CMT, aftershock activity regularities were studied. Rupture plane in the source was defined with high probability. Information and pictures about destructions and damages of buildings on the territory of Tekeli town as well as isoseismal map are shown. In 1993 almost at the same place the earthquake with the same focal parameters and processes occurred. Very close parameters of seismic effects on the territory of Almaty having two almost the same sources were noted.  相似文献   

Structural characterization and composition of Y-rich hainite from Sakharjok nepheline syenite pegmatite (Kola Peninsula,Russia)     

L. Lyalina  A. Zolotarev Jr  E. Selivanova  Ye. Savchenko  D. Zozulya  S. Krivovichev  Yu. Mikhailova 《Mineralogy and Petrology》2015,109(4):443-451

  相似文献   

Determining the Inclination of the Kiloparsec-Scale Jet of the Quasar 3C 273 Based on Competition of Mechanisms for the Knot X-ray Emission     

M. S. Mikhailova  E. Yu. Bannikova  V. M. Kontorovich 《Astronomy Reports》2010,54(6):481-488

Based on the idea that the X-ray emission of the knots in the kiloparsec-scale jet of 3C 273 located closest to the active nucleus is due to inverse Compton scattering on the quasar radiation, while the X-ray emission of knots further from the nucleus is due to inverse Compton scattering on the cosmic microwave background, we find that the angle of the jet to the line of sight is θ ≈ 30°. The magnetic field and electron density in the knots are estimated. It is concluded that there is a break in the electron-energy spectrum at a Lorentz factor of г ∼ 10⁶. It is shown that the energy density of the relativistic electrons in the knots appreciably exceeds the energy density in the magnetic field.  相似文献   

Long-term variations in river and sea factors responsible for the hydrological regime and morphological structure of the Thames River mouth area     

M. V. Mikhailova 《Water Resources》2011,38(4):438-452

General geographic features of the Thames River, its basin, and mouth area, consisting of the tidal mouth reach of the river, a large estuary, and an open nearshore zone of the river mouth (the North Sea coastal zone) are discussed. The peculiarities of river and sea hydrological factors responsible for the regime of the Thames River mouth area are described in detail. Characteristics of the river water runoff were specified and supplemented by the data on the river inundations in the area of London. Particular emphasis was placed on variations in the mean sea level in the area of the Thames River mouth as well as on specific features of tides and storm surges in the area of the sea inlet into the estuary. Main regularities in the estuary evolution during Holocene and present-day morphological processes in the Thames River mouth area were revealed.  相似文献   

Stresses and strains in a layer above moving blocks of a basement (According to mathematical and physical simulations)     

A. V. Mikhailova 《Izvestiya Physics of the Solid Earth》2010,46(5):433-439

  相似文献   

On the causes of decrease in the surface temperature of water in the karkinitskii bay of the black sea     

é. N. Mikhailova  A. B. Polonsky  M. A. Muzyleva 《Physical Oceanography》2012,21(6):394-400

  相似文献   

Deep heterogeneity of the stress state in the horizontal shear zones     

Yu. L. Rebetsky  A. V. Mikhailova 《Izvestiya Physics of the Solid Earth》2014,50(6):824-838

The formation structures of brittle destruction in a rock layer above an active strike-slip fault in the crystalline basement is studied. The problem is analyzed from the standpoint of loading history, when after the stage of pure gravitational loading, an additional strain state of uniform horizontal shear of both the layer and underlying basement develops, which is further followed by a vertically nonuniform shear caused by the activation of the deep fault. For the studied object, irreversible fracture deformations on macro- and microlevels arise as early as the initial stage of loading under the action of gravitational stresses. These deformations continue evolving on the megascopic level in the course of horizontal shearing that is quasi-uniform both along the depth and laterally. The final formation of the structural ensemble occurs after a long stage of horizontal displacement of the blocks of the crystalline basement—the stage of localized shear. The theoretical analysis of the evolution of the stress state and morphology of the failure structures established the presence of numerous fractures with the normal dip-slip components in the intermediate-depth part of the rock mass, which are formed at the stages of uniform and localized horizontal shearing. The fractures with a strike-slip component mainly arise in the upper and near-axial deep parts of the section.  相似文献