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11.
Automated derivation and spatio-temporal analysis of landslide properties in southern Kyrgyzstan 总被引：1，自引：0，他引：1
Darya Golovko Sigrid Roessner Robert Behling Birgit Kleinschmit 《Natural Hazards》2017,85(3):1461-1488
The study area located in southern Kyrgyzstan is affected by high and ongoing landslide activity. To characterize this activity, a multi-temporal landslide inventory containing over 2800 landslide polygons was generated from multiple data sources. The latter include the results of automated landslide detection from multi-temporal satellite imagery. The polygonal representation of the landslides allows for characterization of the landslide geometry and determination of further landslide attributes in a way that accounts for the diversity of conditions within the landslide, e.g., at the landslide main scarp opposed to its toe. To perform such analyses, a methodology for efficient geographic information system (GIS)-based attribute derivation was developed, which includes both standard and customized GIS tools. We derived a number of landslide attributes, including area, length, compactness, slope, aspect, distance to stream and geology. The distributions of these attributes were analyzed to obtain a better understanding of landslide properties in the study area as a preliminary step for probabilistic landslide hazard assessment. The obtained spatial and temporal attribute variations were linked to differences in the environmental characteristics within the study area, in which the geological setting proved to be the most important differentiating factor. Moreover, a significant influence of the different data sources on the distribution of the landslide attribute values was found, indicating the importance of a critical evaluation of the landslide data to be used in landslide hazard assessments. 相似文献
12.
K. Stojanović Br. Jovančićević Dr. Vitorovi G. S. Pevneva Ju. A. Golovko A. K. Golovko 《Geochemistry International》2007,45(8):781-797
Aiming at improved classification of crude oils, naphthalene and phenanthrene isomerization and dealkylation processes were
considered in detail as a possible basis to select new maturation parameters. Crude oils originating from the Banat depression
(Southeastern Pannonian Basin, Serbia) were used as objects of our study. Four new maturation parameters are proposed in this
paper. Two of them are based on dimethylnaphthalene (DMN) and trimethylnaphthalene (TMN) isomerization reactions: DNx = (1,3-DMN + 1,6-DMN)/(1,4-DMN + 1,5-DMN) and TNy = (1,3,6-TMN + 1,3,7-TMN)/(1,3,5-TMN + 1,4,6-TMN). The other two are based
on demethylation of dimethyl-and trimethylphenanthrenes (DMP and TMP) into corresponding methylphenanthrenes (MP): MDR = ΣMP/ΣDMP
and MTR = ΣMP/ΣTMP. The new parameters’ advantageous applicability was demonstrated by factor analysis, comparing them with
maturation parameters known from literature.
The text was submitted by the authors in English. 相似文献
13.
The dynamics of active regions have been investigated using multi-fractal analysis methods, based on magnetograms of the full solar disk in the 630.2 nm line obtained with the SOLIS vector spectromagnetograph of Kitt Peak Observatory (USA) during 2006?C2007 and January 1, 2009?CApril 12, 2010. The applied method of multi-fractal segmentation reveals the appearance of new magnetic fluxes on the Sun disk. A comparison of these fluxes with flare activity shows that the flares are generated in areas of interaction of emerging fluxes with existing structures. 相似文献
14.
Aleksandra Šajnović Ksenija Stojanović Branimir Jovančićević Anatoly Golovko 《Environmental Geology》2009,56(8):1629-1641
Sediments from the Valjevo-Mionica Basin of Neogene age were investigated in this study using different geochemical methods.
The results of the inorganic part analyses suggest that during genesis of the sediments, the contents of Na2O, B and As changed the most, which indicates that genesis of the investigated sediments was followed by climate changes and
volcanic activity. The quantity of other macro- and microelements did not vary significantly. Investigations of the organic
substance showed that it is native organic matter, which has been preserved to a significant extent, formed predominantly
of algal precursor organisms, which provided good quality, deposited under reducing conditions and that it is at a low maturity
level. As it has been established that genesis of the investigated sediments was mostly affected by an arid climate with more
intensive salinity, the aim of this study, was also to identify the processes which were the most affected by the change in
salinity, as well as biomarkers which are the most sensitive to this change. The results led to the conclusion that the salinity
increase in the depositional environment had a primary effect on the preservation of the organic substance and the formation
of the mineral searlesite. In addition, it was noticed that besides the Sq/nC26 ratio, the parameters nC17/nC27, CPI and Ph/nC18, are also significantly sensitive to salinity change in a depositional environment in case of immature organic substance
deposited under reducing conditions. 相似文献
15.
A series of subflares in active region NOAA 9077 (July 2000) and in the activity complex NOAA 0039 + NOAA 0050 were investigated. The structure functions and their characteristics for sets of images of active regions in the hydrogen-alpha line (H-line) were calculated. The ranges of the spatial scales of different scaling behavior of the structure functions were revealed. The existence of intermittent turbulence (multi-fractal structure) in active regions of the chromosphere is shown. Peculiarities of the scaling parameters variations of the structure functions at pre-flare stage are investigated. It was found that on average 20 min before a subflare onset considerable deviation of these variations from the mean occurs, which may be of importance for predictions. It was discovered that maximum variations of scaling parameters with an accuracy to 15 min (on average), in a number of cases coincide with variations of the elongated chromospheric structures in an active-region area. We used H_ filtergrams obtained with the chromospheric telescope of the Baikal observatory operated by ISTP SD RAS. The telescope is coupled with a Halle birefringent filter with a 0.05 nm bandpass, and a Princeton Instruments 2048 × 2048 pixel CCD camera with 16-bit amplitude resolution. 相似文献
16.
Geomagnetism and Aeronomy - The potential to diagnose the beginning of the solar cycle based on the detection of small-scale magnetic formations, the magnetic nodes of ephemeral active regions in... 相似文献
17.
Based on the experimentally measured parameters of elemental composition, average molecular masses, and PRM spectrometry data, we calculated the average structural parameters of resin and asphaltene molecules in Paleozoic crude oil of some oilfields in the Timan–Pechora petroliferous basin. The values of the structural parameters of cyclic and aliphatic fragments in the molecules of resin–asphaltene components of the crudes studied here are within the ranges established earlier for high-molecular compounds of crudes from other petroliferous basins. The average structural-group characteristics of resins in crudes from carbonate reservoirs vary over narrow ranges of values independently of the age and depth of occurrence of the reservoir. The resinous fractions of crudes from terrigenous horizons show symbatic enrichment with paraffin fragments and depletion with naphthene fragments of molecules with depth. This points to the presence of a paragenesis of petroleum hydrocarbons and heteroatomic compounds in the Earth’s interior. 相似文献
18.
The composition and distribution of alkyl-substituted bi- and tricyclic aromatic hydrocarbons were studied in dispersed organic
matter (DOM) samples from four levels of the Middle Jurassic sequences of the southeast of Western Siberia. It was shown that
differences in the distribution of alkylnaphtalenes and alkylphenanthrenes were caused by catagenetic factors, which promoted
the occurrence of the secondary reactions of isomerization, alkylation, and dealkylation. The data on the composition of saturated
and alkyl aromatic hydrocarbons were examined by principal component factor analysis, the results of which were used to divide
the samples into natural families. The grouping of DOM samples is based on the similarity of their characteristic compositional
parameters. It was shown that the families include samples from different units occurring at different depths and mostly in
widely separated localities. This indicates that sediments accumulated and were transformed under similar conditions at different
time periods and in different parts of the petroleum-bearing regions of the southwestern part of Western Siberia. 相似文献
19.
A multifractal analysis of the Hα images for an active region has been performed; the singularity spectra and segmented images
for a narrow range of fractal dimensions have been computed for them. The segmented images show the presence of singular areas
where the singularity index takes on maximum values. These areas mark the active sites of flares. 相似文献
20.
A fractal analysis of narrowband images of the chromosphere and transition layer has been performed in order to study regimes of turbulence and their variations during time-varying processes in active regions. The NOAA 10039 and 10050 activity complexes on July 31, 2002, were observed at Baikal astrophysical observatory of ISZF SO RAN in the H-α line using a chromospheric telescope equipped with a Halle birefringent filter (BF) with a passband of 0.5 Å. Images of the same activity complexes in the spectral band centered at the FeXI 171 Å line, obtained at TRACE space observatory, have been processed using the same technique. The method of structure functions has been used to compute the time series of the scaling parameters. The power spectra of two-dimensional images have been used to compute the time variations in the fractal dimension of the considered activity complex. It has been indicated that the parameters of a multifractal structure (intermittent turbulence) demonstrate jump-like and quasiperiodic time variations correlating with flares. These variations were detected in the H-α and FeXI 171 Å lines of the transition zone, using the ground-based and onboard measurements, which demonstrates that they are of the solar origin. 相似文献