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11.
The Miocene Kahramanmara? Peripheral Foreland Basin (KPFB) resemble to classic foreland basin model, with small differences. In the classic model, both the accretionary wedge and foredeep extend lengthways parallel to the plate margin. In addition, accretionary wedge includes wedge top basin or piggy back basin that extends parallel to foredeep. However, the accretionary wedge of the KPFB contains small half-graben type basins that obliquely intersect the plate margin between the Arabian Plate and the Anatolide–Taurides Platform (due to the irregular shape of the plate boundary). Tectonic lineaments controlled the shape and orientation of these basins and larger main depocentre of the KFPB, which were predominantly filled with deep-sea sediments. This paper focuses on the provenance of features of the KFPB, predominantly was fed from the northern basin margin, while also aiming to resolve the complex basin evolution that occurred during the Miocene.Clasts of Palaeozoic and Mesozoic limestone and ophiolites are common components of the confined deep-water clastic systems, which evolved as elongated trenches in the north-western sector of the KPFB during the Early-Middle Miocene. During the Middle Miocene, continuous thrusting of the northern basin margin to south caused depocentre migration to south-east, through the basin interior. At that time, the north-east and central depocentres of the KPFB were filled primarily by clasts of ophiolite and metamorphic units. The tectonic control on basin fill architecture can be observed anywhere in the KFPB. The principal tectonic features controlled the geometry and orientation of the canyon, the channel geometry of the deep-water slope on the northern basin margin, the frequency and distribution of slump-slide-debris flows and the overall pattern of sedimentation cycles in the stratigraphy of the slope and the central basin floor. Some basin sectors have continuously reactivated and as a result, different sediment entry points with substantial local accumulation of sediment and deformation have evolved on the slope and basin floor. Three scales of provenance were used to investigate the source rock: (a) field-based observation and analysis of conglomerate clasts, (b) modal analysis of sandstone facies and (c) geochemical analysis, all of which were in agreement. 相似文献
12.
Numerical investigation of stochastic response of an elevated water tank to random underground blast loading 总被引：2，自引：2，他引：0
Kemal Hacıefendioğlu Kurtuluş Soyluk Fahri Birinci 《Stochastic Environmental Research and Risk Assessment (SERRA)》2012,26(4):599-607
This paper presents a stochastic finite element seismic response study of a water tank subjected to random underground blast-induced
ground motion. Such tanks contain water and hazardous chemical substances, which implies significant risk to human life, serious
environmental pollution, and considerable economic loss. The random blast-induced ground motion is represented by power spectral
density function and applied to each support point of the three dimensional finite element model of the elevated water tank–fluid
interaction system. A parametric study is conducted to estimate the effects of the blast-induced ground motion on the stochastic
response of the elevated water tank system. Therefore, the analyses are carried out for different values of the charge weight
and the distance from the charge centre. Additionally, in order to investigate the effect of the fluid on the stochastic response
of the elevated water tank, three cases with different water levels are considered in the analyses. Finally, it is observed
that underground blast loading considerably changes the stochastic behavior of the elevated water tank system. 相似文献
13.
Philip Y. Chu Gregg A. Jacobs M. Kemal Cambazoglu Robert S. Linzell 《Marine Geodesy》2013,36(4):399-428
In this paper, we discuss the validation of water level and current predictions from three coastal hydrodynamic models and document the resource and operational requirements for each modeling system. The ADvanced CIRCulation Model (ADCIRC), the Navy Coastal Ocean Model (NCOM), and Delft3D have been configured and validated for the Chesapeake Bay region during a Navy exercise. Water level predictions are compared with a NOAA/NOS water level gauge at the Chesapeake Bay Bridge Tunnel location while current predictions are validated with Acoustic Doppler Profiler (ADP) measurement records at three locations in the lower Chesapeake Bay. Statistical metrics such as correlation coefficient and root mean square error (RMSE) are computed. Both the vertically-integrated currents and currents at varying water depths are compared as well. The model-data comparisons for surface elevation indicate all three models agreed well with water level gauge data. The two-dimensional version of ADCIRC, ADCIRC2D, and NCOM yield better statistics, in terms of correlation and RMSE, than Delft3D. For vertically-integrated currents, ADCIRC2D has the smallest RMSE at Thimble Shoal and Naval Station locations while NCOM has the smallest RMSE at Cape Henry. For the horizontal currents over the water column, the fully three-dimensional, baroclinic ADCIRC model, ADCIRC3D, and NCOM both showed better agreement with the ADP measurements. 相似文献
14.
In irrigation areas, ground water salinity (GWS) levels may vary depending on the amount and quality of irrigation water applied and on the activity of the drainage system. GWS plays a vital role in irrigation systems by influencing whether the environment is suitable for plant growth. Hence, it is necessary to monitor changes in GWS both temporally and spatially. Maps are generally used to visualize this information. However, evaluation of temporal and spatial variations of GWS can be difficult because of the necessity of assessing many maps together to understand both temporal and spatial changes. In this study, a data assessment method that can be used for multi‐year ground water salinity evaluations is presented. The method looks at the spatial and temporal relationships between the main salinity classes present in the study area, their typical locations (i.e. areas where the salinity classes are most frequently located), and the alternate salinity classes in those locations in any of the years of the time series. As a case study, the method was applied to multi‐year (1990–2000) GWS observations in the Mustafakemalpasa irrigation project (19 370 ha) in the Marmara region of north‐western Turkey. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
15.
Macronutrients and micronutrients were measured during the phytoplankton bloom period and then seasonally monitored after
the bloom in the polluted Izmir Bay. Iron and the macronutrients (phosphate, ammonium, nitrate, nitrite, and silicate) were
abundant in the waters of the inner and middle sections of Izmir Bay. The iron concentration decreased exponentially from
the eutrophic inner bay to the oligotrophic outer bay. Suboxic–anoxic processes and the resuspension dynamics in the sediment
were the most important factor in the control of iron, ammonium, and phosphate enrichment in the bay beside the anthropogenic
activities. The biological removal of Fe in the inner and middle bay and nonbiological removal in the outer bay were effective
in controlling iron concentration in Izmir Bay. The nitrate, nitrite, and ammonium nitrogen (N) and Si decreased to critical
levels in the middle and outer bay at the end of the summer as long as the concentration of phosphate was high. The N/P ratios
in the bay suggested that N might be the controlling nutrient for phytoplankton growth particularly in the middle and outer
bay throughout summer. Furthermore, Si was also able to have controlling impact probably on diatom growth during autumn and
winter in the inner and middle bay and in the early spring in the outer bay. The N/Si/Chelex labile Fe ratios implied that
the iron could be a critical controlling nutrient for phytoplankton growth during early April in the outer bay unless the
other macronutrients were low. 相似文献
16.
Observing permanent seals with different physical and mechanical characteristics under various conditions in the field is almost impossible. In conjunction with the development of high-speed computer algorithms, numerical simulation has become one of the major means to study the dynamics of such problems. Therefore, this study covers only the numerical approach to analyze the stability of underground seals. In this regard, the purpose of this study is to provide an insight to the design of underground seals by numerically analyzing their behaviors under different static and dynamic explosion overpressures using a geo-technical commercial software FLAC3D. For this purpose, a series of numerical models were constructed for a typical seal in an underground gallery with different properties such as seal thickness, seal dimensions, gallery geometry, and strength of the seal material to investigate the stability of seals exposed to various static and dynamic explosion overpressures. A total of 896 numerical analyses (512 static and 384 dynamic) were performed and evaluated. Regarding the gallery geometry, it was found that seals constructed in trapeze-shaped galleries are more stable than those constructed in horseshoe-shaped galleries having the same dimensions. Moreover, the results showed that the seal stability increases with the increasing seal thickness rather than the strength of the seal material. The statistical analyses suggest that there is a very strong exponential relationship between the seal thickness and the maximum displacement measured at the midpoints of the outer surfaces of the seals. The coefficients of determination values obtained are in the range of 0.92–0.93 and 0.92–0.95 for static and dynamic analyses, respectively. We proposed formulas which use the longer dimension of the seal (W max ), maximum allowable displacement on the seal (D max ), explosion overpressure applied onto the seal (P exp ), and compressive strength of the seal material (σ c and σ cd for static and dynamic conditions, respectively) to predict the minimum required seal thickness (T s ) for static and dynamic conditions. The proposed formulas enable calculating the necessary seal thickness easily if the explosion overpressure (or hydrostatic pressure) is known or approximated. 相似文献
17.
Natural Hazards - Landslides occur when masses of rock, earth, and other debris move down a slope. The slope of an area is directly responsible for the magnitude of the landslide. Being... 相似文献
18.
When analyzing spatial issues, geographers are often confronted with many problems with regard to the imprecision of the available information. It is necessary to develop representation and design methods which are suited to imprecise spatiotemporal data. This led to the recent proposal of the F‐Perceptory approach. F‐Perceptory models fuzzy primitive geometries that are appropriate in representing homogeneous regions. However, the real world often contains cases that are much more complex, describing geographic features with composite structures such as a geometry aggregation or combination. From a conceptual point of view, these cases have not yet been managed with F‐Perceptory. This article proposes modeling fuzzy geographic objects with composite geometries, by extending the pictographic language of F‐Perceptory and its mapping to the Unified Modeling Language (UML) necessary to manage them in object/relational databases. Until now, the most commonly used object modeling tools have not considered imprecise data. The extended F‐Perceptory is implemented under a UML‐based modeling tool in order to support users in fuzzy conceptual data modeling. In addition, in order to properly define the related database design, an automatic derivation process is implemented to generate the fuzzy database model. 相似文献
19.
Sedimentary evidence for late Messinian uplift of the SE margin of the Central Anatolian Plateau: Adana Basin,southern Turkey 
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下载免费PDF全文 Giuditta Radeff Taylor F. Schildgen Domenico Cosentino Manfred R. Strecker Paola Cipollari Güldemin Darbaş Kemal Gürbüz 《Basin Research》2017,29(Z1):488-514
The Adana Basin of southern Turkey, located at the SE margin of the Central Anatolian Plateau in the vicinity of the Arabia‐Eurasia collision zone, is ideally suited to record Neogene and Quaternary topographic and tectonic changes in the easternmost Mediterranean realm. On the basis of our correlation of 34 seismic reflection profiles with corresponding exposed units along the margins of the Adana Basin, we identify and characterize the seismic facies that corresponds to the upper part of the Messinian Handere Formation (ca. 5.45 to 5.33 Ma), which consists mainly of fluvial conglomerates and marls. The seismic reflection profiles indicate that ca. 1100 km3 of the Handere Formation upper sub‐unit is distributed over ca. 3000 km2, reflecting local sedimentation rates of up to 12.5 mm year?1. This indicates a major increase in both sediment supply and subsidence rates at ca. 5.45 Ma. Our provenance analysis of the Handere Formation upper sub‐unit based on clast counting and palaeocurrent measurements reveals that most of the sediment is derived from the Taurus Mountains at the SE margin of the Central Anatolian Plateau and regions farther north. A comparison of these results with the composition of recent fluvial conglomerates and the present‐day drainage basins indicates major changes between late Messinian and present‐day source areas. We suggest that these changes in drainage patterns and lithological characteristics result from uplift and ensuing erosion of the SE margin of the plateau. We interpret the tectonic evolution of the southern flank of the Anatolian Plateau and the coeval subsidence and sedimentation in the Adana Basin to be related to deep lithospheric processes, particularly lithospheric delamination and slab break‐off. 相似文献
20.
Murat Gül Kemal Gürbüz Özgür Kalelioğlu 《Journal of the Indian Society of Remote Sensing》2012,40(2):257-269
The Kahramanmaraş Foreland Basin (KFB) margins are formed by Paleozoic-Mesozoic limestone, metamorphic and ophiolite. This
basin contains sandstone and claystone alternations with lesser amounts of reefal limestone, channelized conglomerates, debrites
and slump deposits. An irregular topography and absence of path obscured the accurate and complete mapping of the basin. Thus,
Landsat TM images were used. The RGB 751 false colour composites were chosen due to abundant claystone and limestone content
of the KFB. The RGB PCA 145 was preferred due to high loading of TM bands 5 (clay and iron oxide mineral), 7 (carbonate mineral),
3 and 1 (albedo and topography). The RGB 5/7-5/1-4 (light green dots in 5/7 indicate enhanced claystone area and OH- bearing alteration zone; red dots in 5/1 indicate enhanced iron oxide bearing alteration zone; fourth band for water bearing
minerals) shows the transportation way of sediments. The OH- and iron oxide bearing alteration zones are found on older source rocks and younger deposition area. Main lithological boundary,
geometry and provenance properties of the KFB were satisfactorily obtained from the Landsat TM images. However, low spatial
resolution (30 m) prevents detail facies discrimination that still requires hard field working and/or detailed satellite images. 相似文献