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121.
Brückner Florian Bahls Rebecca Alqadi Mohammad Lindenmaier Falk Hamdan Ibraheem Alhiyari Mohammad Atieh Ala’a 《Hydrogeology Journal》2021,29(8):2789-2802
Hydrogeology Journal - In 2017, a comprehensive review of groundwater resources in Jordan was carried out for the first time since 1995. The change in groundwater levels between 1995 and 2017 was... 相似文献
122.
Khoshghalb Arman Nobarinia Mohammad Stockton Joshua Kalateh Farhoud 《Acta Geotechnica》2021,16(5):1635-1645
Acta Geotechnica - The purpose of this study is to conduct hole erosion tests (HETs) to better understand the progression of concentrated leaks in compacted soils. While samples with high levels of... 相似文献
123.
Increasing population in urban areas and limitations of suitable lands for developing houses and urban infrastructure have led to the vertical development in cities. However, these developments are managed by a cadastral system which is mainly two-dimensional and cannot efficiently represent Rights, Restrictions, and Responsibilities (RRRs) in complex scenarios. In fact, a three-dimensional cadastre is required for efficiently registering and representing RRRs. In this paper, a 3D proximity analysis was proposed and implemented to determine RRRs and associated easement rights in non-topology-based data structures. This method can be used to investigate the surrounding spaces of a subject apartment unit or storage in a high-rise. The performance of the developed method was evaluated in a large complex high-rise in Tehran, Iran. The results confirmed that the proposed method can correctly identify the neighbor spaces in complex scenarios. 相似文献
124.
In this study, the effect of different sampling rates (i.e. observation recording interval) on the Precise Point Positioning (PPP) solutions in terms of accurac... 相似文献
125.
Historical tsunami in the Makran Subduction Zone off the southern coasts of Iran and Pakistan and results of numerical modeling 总被引:4,自引:0,他引:4
Mohammad Heidarzadeh Moharram D. Pirooz Nasser H. Zaker Ahmet C. Yalciner Mohammad Mokhtari Asad Esmaeily 《Ocean Engineering》2008,35(8-9):774-786
Tsunami hazard in the Makran Subduction Zone (MSZ), off the southern coasts of Iran and Pakistan, was studied by numerical modeling of historical tsunami in this region. Although the MSZ triggered the second deadliest tsunami in the Indian Ocean, among those known, the tsunami hazard in this region has yet to be analyzed in detail. This paper reports the results of a risk analysis using five scenario events based on the historic records, and identifies a seismic gap area in western Makran off the southern coast of Iran. This is a possible site for a future large earthquake and tsunami. In addition, we performed numerical modeling to explain some ambiguities in the historical reports. Based on the modeling results, we conclude that either the extreme run-up of 12–15 m assigned for the 1945 Makran tsunami in the historical record was produced by a submarine landslide triggered by the parent earthquake, or that these reports are exaggerated. The other possibility could be the generation of the huge run-up heights by large displacements on splay faults. The results of run-up modeling reveal that a large earthquake and tsunami in the MSZ is capable of producing considerable run-up heights in the far field. Therefore, it is possible that the MSZ was the source of the tsunami encountered by a Portuguese fleet in Dabhul in 1524. 相似文献
126.
Hua?YuEmail author Yingqian?Xiong Zhenxia?Liu Serge?Berné Chi-Yue?Huang Guodong?Jia 《Geo-Marine Letters》2008,28(3):131-136
Based on new and existing data on oxygen isotopes, alkenone-surface seawater temperature trends, planktonic foraminifers,
lithology, and clay mineral composition of piston cores, a distinct cooling event has been identified around 8,200 cal a b.p. in the middle Okinawa Trough, northwest Pacific. This corresponds to the 8,200 a b.p. cooling event recorded in many places of the Northern Hemisphere. During this event, the local temperature decreased by
1°C, and the δ18O value increased by 0.6‰. A strengthened Asian winter monsoon is the most probable cause for this event, which thus adds
further credibility to the contention that we are dealing here with a global phenomenon. 相似文献
127.
Using seismic and Chirp sonar profiles, this paper tests the hypothesis that hyperpycnal flows are the main factor controlling
the formation and maintenance of the meandering Kaoping submarine canyon off SW Taiwan. Cross-section geometries, and erosional
as well as depositional features vary along the canyon course. In the proximal, sinuous part of the canyon, down-cutting into
the shelf strata has created a relief of 340 m. The cause of this intense erosion of the seafloor is suggested to be the frequent
development of hyperpycnal flows. A seismic section across a meander in the distal part of the canyon shows levees formed
by overspilled sediments at the outer bend, and a terrace characterized by relatively flat stratified facies at the inner
bend. The geological setting and climatic conditions in SW Taiwan (e.g. earthquakes, typhoons, floods), as well as major river–canyon
connections (for example, direct input of highly concentrated suspended sediment) would all promote hyperpycnal flow generation.
This causes axial incision, canyon wall slumping, and the formation of levees by spill-over deposition in the upper reach
of the Kaoping Canyon. 相似文献
128.
Hydrodynamics and sediment resuspension events, induced at the shoreline by a deep-draft vessel passing nearby, are described.
Measurements (pressure, currents and turbidity) were obtained at 4 Hz, on a lower beach ~50 m from a channel where large car
ferries operate in Wootton Creek, Isle of Wight. The study focuses on a representative 8-min 32-s-long record, during which
two large vessels passed the channel section. At the shore, the passage of each vessel induced a long-period water-level drawdown,
followed by a water-level oscillation (seiche) of similar period, and the short-period waves of the wake. Both drawdowns were
the main constituents of the prevailing wave pattern. The second drawdown was the largest in amplitude, in response to a higher
speed of the ferry, and the influence of the seiche which had been activated during the preceding event. Two successive peaks
of turbidity were observed shortly after this drawdown. Analyses of current velocity and direction indicate that the sediments
resuspended originated from the shallower upper beach. Anthropogenically induced erosion of the foreshore is predicted at
Wootton Creek. 相似文献
129.
李致家 《中国海洋湖沼学报》2008,26(2):142-151
Stochastic characteristics of the Benue River streamflow process are examined under conditions of data austerity. The streamflow process is investigated for trend, non-stationarity and seasonality for a time period of 26 years. Results of trend analyses with Mann-Kendall test show that there is no trend in the annual mean discharges. Monthly flow series examined with seasonal Kendall test indicate the presence of positive change in the trend for some months, especially the months of August, January, and February. For the stationarity test, daily and monthly flow series appear to be stationary whereas at 1%, 5%, and 10% significant levels, the stationarity alternative hypothesis is rejected for the annual flow series. Though monthly flow appears to be stationary going by this test, because of high seasonality, it could be said to exhibit periodic stationarity based on the seasonality analysis. The following conclusions are drawn: (1) There is seasonality in both the mean and variance with unimodal distribution. (2) Days with high mean also have high variance. (3) Skewness coefficients for the months within the dry season period are greater than those of the wet season period, and seasonal autocorrelations for streamflow during dry season are generally larger than those of the wet season. Precisely, they are significantly different for most of the months. (4) The autocorrelation functions estimated "over time" are greater in the absolute value for data that have not been deseasonalised but were initially normalised by logarithmic transformation only, while autocorrelation functions for i = 1, 2 365 estimated "over realisations" have their coefficients significantly different from other coefficients. 相似文献
130.
Muhammad Khurshid Mohammad Nafees Abdullah Khan Mehmet Somuncu Ashfaq Ahmad Khan Wajid Rashid 《地理学报(英文版)》2019,29(10):1758-1770
Journal of Geographical Sciences - Pastoralism is a viable socio-economic system-shaped by landless and agro-pastoral communities in many pastoral regions of the world. This system is mainly based... 相似文献