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11.
The paper discusses microseismic monitoring during oil well stimulation by hydraulic fracturing, an emergent technology used
for hydraulic fracturing layer control. The passive monitoring is a new widely developing technology of HFL control. The main
factor affecting the results of passive seismic monitoring is the event location accuracy. The passive monitoring acquisition
system utilizes one three components seismic probe deployed into the observation well. To evaluate the location accuracy of
induced events for one observation well we applied traditional kinematic approach based on picking of earthquake P- and S-waves arrivals. The influence of geometric parameters of geophones location in a borehole, their quantity, picking errors
of waves arrivals on the accuracy of microearthquakes location is studied. 相似文献
12.
Yu. K. Vasil’chuk N. L. Frolova E. D. Krasnova N. A. Budantseva A. C. Vasil’chuk L. V. Dobrydneva L. E. Efimova E. V. Terskaya Ju. N. Chizhova 《Water Resources》2016,43(5):828-838
The isotopic features of Lake Trekhtsvetnoe in the White Sea coast area were studied in 2012–2015 in both winter and summer. Lake Trekhtsvetnoe is a water body, separating from the sea, with constant vertical stratification throughout the observation period. Its isotopic, hydrophysical, and biological characteristics have been studied. By the isotopic profile of lake water body, three zones can be identified in the lake: (1) 0–1 m: mixolimnion zone with δ18O varying from–12 to–11.1‰; (2) 1.0–3.0 m: zone with transitional properties with δ18O varying from–11.1 to–5.5‰; (3) 3.0–7.6 m: monimolimnion zone with highest values of δ18O—from–5.5 to–4.7‰. 相似文献
13.
Multidisciplinary studies of the separating lakes at different stage of isolation from the White Sea performed in March 2012 总被引:1,自引:0,他引:1
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Geochemical nature and age of the plagiogranite-gabbronorite association of the oceanic core complex of the Mid-Atlantic ridge at 5°10′S 总被引:1,自引:0,他引:1
S. A. Silantyev J. Koepke A. A. Ariskin M. O. Anosova E. A. Krasnova E. O. Dubinina G. Suhr 《Petrology》2014,22(2):109-127
Our newly obtained data on the geochemistry and age of plagiogranite-gabbronorite association in the oceanic core complex of the Mid-Atlantic Ridge (MAR) at 5°10′S suggest close genetic relations between these rocks in this segment of the ridge. The U/Pb zircon age of an oceanic plagiogranite (OPG) sample is 1.059 ± 0.055 Ma and is in good agreement with the zircon age of plutonic rocks in the oceanic core complex of northern MAR. A distinctive geochemical feature of the rocks is their unusually depleted 87Sr/86Sr and 143Nd/144Nd ratios, which suggest that the plutonic rocks of the gabbronorite-plagiogranite association in MAR at 5°10′S could be derived from the most strongly depleted mantle reservoir of all known to occur beneath the axial MAR zone. The COMAGMAT-5.2 numerical thermodynamic simulation of the possible crystallization links between the plagiogranite and gabbronorite from the MAR segment at 5°10′S led us to conclude that the leading role in the origin of the plagiogranite was played by a two-stage process: the partial melting of the gabbronorite and the subsequent fractionation of the newly generated melt. The regional differences between the isotopic-geochemical parameters of MAR plagiogranites can, perhaps, reflect local specifics of so-called hydrothermal anatexis, such as the geochemical features of the rocks involved in this process and the parameters of the hydrothermal process, for example, variations in the W/R ratio. 相似文献
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Water Resources - Meromictic water bodies (water bodies with stable vertical water stratification, which forms because of a difference between the density of its layers) is a rare phenomenon, which... 相似文献
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Water Resources - Based on the analysis of scientific literature for the period from the end of the XIX century to the present, as well as the author’s own research, the information about... 相似文献
18.
I. F. Gertner V. V. Vrublevskii A. M. Sazonov T. S. Krasnova Yu. V. Kolmakov E. A. Zvyagina P. A. Tishin D. N. Voitenko 《Doklady Earth Sciences》2009,427(2):961-967
The first data are presented on the distribution of rare elements and isotope composition of neodymium and strontium in the
rocks of the alkaline-ultramafitic association of the Kresty volcanoplutonic structure (one of the probable satellites of
the Gulinian massif being the largest in the Maimecha-Kotui alkaline province in Polar Siberia). On the basis of the results
of geochemical studies performed and formerly obtained geophysical and isotope data, a new model is proposed for the plume
nature of magmatism in the region, based on the action of a single mantle source of the PREMA type and its active interaction
with the matter of the Earth’s crust. 相似文献
19.
The structure of the reproductive gathering of beluga whales (RG) was studied near Cape Beluzhii in the Solovetsky Islands
in the White Sea by the photo identification of individuals in 2007–2008; in addition, the peculiarities of the seasonal and
interseasonal dynamics of the RG incomings were analyzed. The gathering is formed by predominantly females and calves of different
ages, which visit the RG area as stable “family” groups. About 15% of the observed females come to Beluzhii Cape every year
and stay there during the whole summer season; thus, forming the regular part of the RG. The other animals come there for
a certain time period, which is probably preconditioned by their physiological readiness for coupling and procreation for
some of the females. When comparing our data with the catalogue of the visually registered beluga whales’ markers (1996–2008),
we found that most of the identified animals of the Solovetsky RG appear here during one summer season or even with an off
period of several years despite the significantly regular findings of most of them for this area. We conclude this may be
linked with the natural changes of the individual markers due both to the shedding and the sexual cycle in the mature animals.
Our data allow concluding that the total population of the Solovetsky PG is higher than was reported before using the visual
supervision methods. 相似文献
20.
S. A. Silantyev N. S. Bortnikov K. N. Shatagin V. E. Bel’tenev N. N. Kononkova Ya. V. Bychkova E. A. Krasnova 《Petrology》2016,24(4):336-366
The paper presents petrological and geochemical data on mantle peridotite, basalt, and metamorphic rocks sampled in Cruise 36 of the R/V Professor Logachev at the MAR axial zone between 17° and 20° N. These data are interesting not only as providing new information on the inner structure of the oceanic crust in the still-poorly known axial MAR segment but also in the context of the fundamental problem of interaction between magmatic and hydrothermal systems in slow-spreading mid-oceanic ridges. The MAR axial zone between 17° and 20° N was determined to host both weakly and strongly depleted residual peridodites, which suggests that the degree of mantle source melting significantly varied along the ridge axis in this segment. The MAR crest zone comprises slabs of serpentinized peridotite brought to the seafloor surface at various time. The most strongly depleted mantle peridotites likely uplifted later than the mildly and weakly depleted rocks in the same areas. A mantle reservoir beneath the MAR axial zone at 20° N is not isotopically related to the mantle source of the parental MORB melts, and high-Mg metabasites exposed at 17°56- N were derived from a crustal source that was modified near the root zone of a high-temperature hydrothermal system. The studied area seems to display traces of an extinct hydrothermal field and likely an ore occurrence related to it. 相似文献