An investigation of trends in precipitation volume for the last three decades in different regions of Fars province, Iran   总被引：1，自引：1，他引：0  

Hossein Ahani  Mehrzad Kherad  Mohammad Reza Kousari  Mehdi Rezaeian-Zadeh  Mohammad Amin Karampour  Faezeh Ejraee  Saeedeh Kamali 《Theoretical and Applied Climatology》2012,109(3-4):361-382

Under condition of climate changes as global warming, monitoring and detecting trend of precipitation volume is essential and will be useful for agricultural sections. Considering the fact that there were not enough research related to precipitation volume, this study aimed to determine trends in precipitation volume, monthly and annually in different regions of Fars province for the last three decades (33?years period; 1978–2010). Fars province is located in arid and semi-arid regions of Iran, and it plays an important role in agricultural production. Inverse distance weighting interpolation method was used to provide precipitation data for all regions. To analyze the trends of precipitation volume, Mann–Kendall test, Sen’s slope estimator, and 10-year moving average low-pass filter (within time series) were used. The negative trends were identified by the Sen’s slope estimator as well as Mann–Kendall test. However, all the trends were insignificant at the surveyed confidence level (95%). With regards to the application of 10-year moving average low-pass filter, a considerable decreasing trend was observed after around year 1994. Since one of the most important restrictions in agricultural development of the Fars province is lack of sufficient water resources, any changes onward to lack of sufficient precipitation impose impressive pressure and stress on valuable resources and subsequently agricultural production.  相似文献   

Observed changes in relative humidity and dew point temperature in coastal regions of Iran   总被引：2，自引：0，他引：2  

P. Hosseinzadeh Talaee  A. A. Sabziparvar  Hossein Tabari 《Theoretical and Applied Climatology》2012,110(3):385-393

The analysis of trends in hydroclimatic parameters and assessment of their statistical significance have recently received a great concern to clarify whether or not there is an obvious climate change. In the current study, parametric linear regression and nonparametric Mann?CKendall tests were applied for detecting annual and seasonal trends in the relative humidity (RH) and dew point temperature (T _dew) time series at ten coastal weather stations in Iran during 1966?C2005. The serial structure of the data was considered, and the significant serial correlations were eliminated using the trend-free pre-whitening method. The results showed that annual RH increased by 1.03 and 0.28?%/decade at the northern and southern coastal regions of the country, respectively, while annual T _dew increased by 0.29 and 0.15°C per decade at the northern and southern regions, respectively. The significant trends were frequent in the T _dew series, but they were observed only at 2 out of the 50 RH series. The results showed that the difference between the results of the parametric and nonparametric tests was small, although the parametric test detected larger significant trends in the RH and T _dew time series. Furthermore, the differences between the results of the trend tests were not related to the normality of the statistical distribution.  相似文献   

Application of integrated geoelectrical methods in Khenadarreh (Arak,Iran) graphite deposit exploration     

Hamidreza Ramazi  Mohammad Reza Hossein Nejad  Aenollah Azizzadeh Firoozi 《Journal of the Geological Society of India》2009,74(2):260-266

This paper is devoted to application of SP, resistivity and mise-a-la-masse method in Khenadarreh (Arak, Iran) graphite deposit exploration. Mise-a-la-masse method is one of the main geophysical exploration methods used to investigate conductive bodies with outcrops on the surface or in exploratory pits. By integrating mise-a-la-masse results with other geoelectrical methods, such as self-potential and resistivity surveys, useful results can be acquired. Powerful survey design, data processing and interpretation methods can make geoelectrical surveying results more reliable. Here, we applied integrated geoelectrical methods to explore the Khenadarreh-bala graphite deposit in the Sarband region of the Markazi province, Iran. We present a new and simple method for processing and interpreting mise-a-la-masse data, which corrects for the effect of distance from the current electrode in the conductive body. After correction, the residual potential values corresponded with the SP results and the apparent resistivity pseudosections. The geophysical results were confirmed by drill holes in the study area.  相似文献   

The Miduk porphyry Cu deposit,Kerman, Iran: A geochemical analysis of the potassic zone including halogen element systematics related to Cu mineralization processes   总被引：1，自引：0，他引：1  

Mohammad Boomeri  Kazuo Nakashima  David Richard Lentz 《Journal of Geochemical Exploration》2009

Miduk hypogene and supergene porphyry Cu–Mo mineralization occurs within the Miocene porphyritic quartz–diorite and host Eocene plagioclase–hornblende phyric andesitic pyroclastic and flow sequence. Both the host rocks were extensively altered by hydrothermal fluids to dominantly potassic, phyllic, and argillic with interstitial to distal propylitic types.  相似文献   

Biostratigraphy and Sequence Stratigraphy of the Tarbur Formation (Maastrichtian) from Iranian Zagros Foreland Basin, Southwest of Iran     

Hossein GHANBARLOO  Amrollah SAFARI  Hossein VAZIRI-MOGHADDAM 《《地质学报》英文版》2022,96(1):147-166

Shallow carbonate deposits(Tarbur Formation)were formed in the Zagros foreland basin with dynamic tectonics during the Maastrichtian age.From the viewpoint of reconstruction of depositional conditions in these deposits,studies of biostratigraphy,microfacies,microtaphofacies,and sequence stratigraphy were performed in a single area at Tang-e Shabi Khoon,northwest of Zagros.Based on the identification of two assemblage zones consisting of benthic foraminifera in these strata,the formation was deposited during the middle to late Maastrichtian.The number of cycles in test size and type of coiling in Loftusia decreased from the study area toward the northwest of the Neotethys basin.The input of clastic sediments affected the distribution of Loftusia and rudists in the study area.Nine microfacies,six microtaphofacies,and one terrigenous facies(shale)were identified based on the sedimentary features.These deposits of the middle-late Maastrichtian were deposited on a homoclinal carbonate ramp.The platform can be divided into restricted and semi-restricted lagoon,shoal,and open marine environments.In the study area,the deposits of the Tarbur Formation were deposited during four third-order depositional sequences.Local fault activities affected the formation of depositional sequences in the study area.  相似文献   

Simulating urban growth in a megalopolitan area using a patch‐based cellular automata          下载免费PDF全文

Sanaz Alaei Moghadam  Mohammad Karimi  Kyoumars Habibi 《Transactions in GIS》2018,22(1):249-268

Although traditional cellular automata (CA)‐based models can effectively simulate urban land‐use changes, they typically ignore the spatial evolution of urban patches, due to their use of cell‐based simulation strategies. This research proposes a new patch‐based CA model to incorporate a spatial constraint based on the growth patterns of urban patches into the conventional CA model for reducing the uncertainty of the distribution of simulated new urban patches. In this model, the growth pattern of urban patches is first estimated using a developed indicator that is based on the local variations in existing urban patches. The urban growth is then simulated by integrating the estimated growth pattern and land suitability using a pattern‐calibrated method. In this method, the pattern of new urban patches is gradually calibrated toward the dominant growth pattern through the steps of the CA model. The proposed model is applied to simulate urban growth in the Tehran megalopolitan area during 2000–2006–2012. The results from this model were compared with two common models: cell‐based CA and logistic‐patch CA. The proposed model yields a degree of patch‐level agreement that is 23.4 and 7.5% higher than those of these pre‐existing models, respectively. This reveals that the patch‐based CA model simulates actual development patterns much better than the two other models.  相似文献   

On Inflow to a Tunnel in a Fractured Double-Porosity Aquifer     

Mohammad M. Sedghi  Hongbin Zhan 《Ground water》2021,59(4):562-570

Inflow to a tunnel is a great public concern and is closely related to groundwater hydrology, geotechnical engineering, and mining engineering, among other disciplines. Rapid computation of inflow to a tunnel provides a timely means for quickly assessing the inflow discharge, thus is critical for safe operation of tunnels. Dewatering of tunnels is another engineering practice that should be planned. In this study, an analytical solution of the inflow to a tunnel in a fractured unconfined aquifer is obtained. The solution takes into account either the spherical or slab-shaped matrix block and the unsteady state interporosity flow. The instantaneous drainage water table and anisotropic hydraulic conductivities of the fractures network are also considered. Both uniform flux and uniform head boundary condition are considered to simulate the constant head boundary condition in the tunnel. The effects of the hydraulic parameters of the fractured aquifer on the inflow variation of the tunnel are explored. The application of the presented solution to obtain the optimum location and discharge of the well to minimize the inflow to a tunnel is illustrated.  相似文献   

Geostatistical Algorithm Selection for Mineral Resources Assessment and its Impact on Open-pit Production Planning Considering Metal Grade Boundary Effect     

Maleki  Mohammad  Madani  Nasser  Jélvez  Enrique 《Natural Resources Research》2021,30(6):4079-4094

Mine planning is influenced by many sources of uncertainty. Significant sources of geological uncertainty in mine planning include uncertainty in layout of geological domains and uncertainty in metal grades. These two sources of uncertainty cannot be modeled separately because the distribution of the grade is controlled usually by geological domains. Two approaches exist for combining these two sources of uncertainty: the joint simulation approach and the cascade approach. In this paper, these two approaches were compared using a real case study. To this end, uncertainty in iron grade (quantitative variable) and ore zones (qualitative variable) was modeled using both approaches. There were some considerable differences in the results obtained by each approach, which confirm the importance of choosing the most appropriate approach with consideration of the dominate features of a deposit.

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Experimental Investigation of Wettability Alteration from Water-wet to Oil-wet During Oil Migration     

Gholinezhadateni  Mohammad  Rostami  Behzad 《Natural Resources Research》2021,30(5):3735-3746

Natural Resources Research - Most oil reservoirs are first saturated with water and become oil-wet gradually due to oil migration and accumulation. Previous studies reported that the adsorption of...  相似文献   

A Novel Multiple-Kernel Support Vector Regression Algorithm for Estimation of Water Quality Parameters     

Najafzadeh  Mohammad  Niazmardi  Saeid 《Natural Resources Research》2021,30(5):3761-3775

Natural Resources Research - The quality of surface waters plays a key role in the sustainability of ecological systems. Measuring water quality parameters (WQPs) is of high...  相似文献