Search published articles


Showing 6 results for Cru
Crustal Study in the West of Iran Based on Travel Time Curves of Local Earhquakes

Volume 3, Issue 1 (11-2009)
Abstract
(Paper pages 563-590) This study explores crustal velocity structure in the west of Iran. Wealth of data from recorded local earthquakes creates an opportunity to image crust and upper mantle in the region and then these data use for the joint inversion method in this region. We proposed to study velocity and interface structure of the crust and upper mantle in the west of Iran using local earthquakes recorded in the Kermansha short-period seismic stations at the Institute of Geophysics, University of Tehran (IGUT), and the Sanandaj broad-band seismic station at the International Institute of Earthquake Engineering and Seismology (IIEES), since 2004. The earthquakes and stations should be directed for the travel time curve analysis. Recorded earthquakes were classified along the five separate profiles and 278 earthquakes (mb≥3) separate in data (3000) and epicenter distance is 10-750 km, that corresponding travel-time curves were analyzed. Moreover, crustal velocity structure is determined based on the travel time curve of local event. So, algorithm program was written and arrival times of body waves compare with forward modeling code was written, in order to refine final model. This processing based on earthquakes with mb≥4 and the error RMS is 0.01-0.26 sec. Compressional wave velocity of the crust is 6.23±0.07 km/s and the upper mantel (Moho) is 8.08±0.08 km/s. since, shear waves velocity for the crust, found to be 3.64±0.06 km/s and the upper mantel (Moho) is 4.70±0.01 km/s. Depths for Conrad and Moho discontinuities were obtained 11±2 km and 43±3 km respectively, which well correlate with the results of the previous gravimetric crustal studies
Determining Appropriate Natural Caves for Underground Crude Oil Storage by Admixture FAHP and TOPSIS Methods
A Soltanalizadeh, A Ramezanzadeh, Me Jalali,
Volume 8, Issue 3 (12-2014)
Abstract
The world financial crisis has drastically raised the costs of hydrocarbon materials. This simply manifests the strategic significance of crude oil storage. Regarding the special rank of the oil in Iran’s economy, storage industry development can be one of the solutions to control such a crisis. Underground storage of crude oil in synthetic structures (rock caverns, salt caverns, and obsolete mines) and natural structures (depleted fields of oil and gas, underground water resources, and natural caves) is possible. Among these possibilities more adaptable to the environment is the most appropriate. Due to the existence of many caves in Iran, crude oils storage in natural caves is a proper option. It is clear that if natural caves are used instead of caverns, much can be saved. The present article intends to choose a proper cave for crude oil storage through studying the natural caves based on a combination of fuzzy analytical hierarchy process (FAHP) and technique for order performance by similarity to idea solution (TOPSIS). The likely option is chosen. Roudafshan Cave is considered appropriate for crude oil underground storage based on several qualitative and quantitative criteria including tourism and environment protection regulations, capacity, distance from both main pipes of crude oil transfer and country's major petroleum factories. It should be noted that these criteria are ranked by an experienced team. This cave is located in the north east of Tehran in Firoozkooh and has three passageways which are among the largest ones in the country. Generally, its capacity is estimated to be about 250,000 square meters
Identification and Stabilization of Dispersive Soils: Case Study of Water Transfer Canal of Simindasht-Garmsar
Abdolhosein Haddad, Hamed Javdanian, Faezeh Ebrhimpour,
Volume 11, Issue 1 (8-2017)
Abstract
./files/site1/files/2Extended_Abstract.pdfExtended Abstract
(Paper pages 29-50)
Introduction
In some soils, special phenomena happen with increases in their moisture content that sometimes inflict major damages on development projects. Dispersive soils are one type of such soils. The physico-chemical properties of the particles in dispersive soils cause them to disperse and separate from each other upon contact with water. If dispersive clays are not accurately identified, they will cause damages and failures. In the Simin Dasht region of Semnan Province, some hydraulic structures have incurred serious damages because they are located on dispersive soils.
The present research studied the soils around the canal transferring water from the Simin Dasht to Garmsar. This 37-kilometer long canal is situated in Semnan Province between the Simin Dasht and the Garmsar diversion Dams. Scouring and soil erosion under the concrete lining of the canal has led to the destruction of the structure. After visiting the site and taking soil samples, double hydrometer and pinhole tests were performed. The effects of adding various amounts of cement, lime and aluminum nitrate on amending dispersive clays were studied and compared in the Simin Dasht region of Semnan Province.
Experiments
The effects of the quantities of cement, lime and aluminum amendment materials on stabilization of dispersive soils in the Simin Dasht region of Semnan Province were investigated. Two types of dispersive clayey soils were amended. Table 1 presents the characteristics of the soils. The effects of various amounts of lime, cement, and aluminum nitrate on reduction in the degree of dispersion in the tested soils were studied. The cement, lime, and soil samples were dried at 40˚C for 24 hours. It must be mentioned that the amount of added lime, cement, and aluminum nitrate were zero, 3, 5, and 7 percent.
Table1. Characteristics of dispersive soils used in this reserch
Gs Optimum Moisture (%) Plasticity Index, PI (%) Plastic limit, PL (%) Liquid limit, LL (%) Natural water content (%) Soil
2.72 15 2.54 15.09 17.63 13.84 A
2.66 11 6.33 16.11 22.44 3.02 B


Results
Average changes in discharge passing through the dispersive soil samples A and B, and through samples of these soils amended with lime, cement, and aluminum nitrate in pinhole tests are presented in Figures 1(a-f), respectively. Figure 1a indicates that the behavior of the A soil samples amended with lime did not follow any specific trend, but we can cautiously say that soil A will become non-dispersive when lime is added at 4.5 percent at all moisture contents. Increases in the quantities of the cement added to the dispersive soils A and B to stabilize them independent of the moisture content of the soils were also investigated (Figure 1c, d). Behavior of the A soil samples stabilized with aluminum nitrate followed a specific trend (Figure 1 e, f) contrary to those amended with the other stabilizers.
Conclusions
Results of the tests show that dispersion in soil A was amended (without completely preventing the occurrence of the scouring phenomenon) by the addition of cement or lime at 5 percent or aluminum nitrate at 3 percent. Moreover, dispersion in soil B was amended by the addition of cement at 3 percent, lime at 5 percent, or aluminum nitrate at 3 percent. Aluminum nitrate was a better and more effective amendment material for the dispersive soils compared to lime. Therefore, aluminum ions replaced the other ions in the structure of dispersive clays more suitably compared to calcium ions. Comparison of the results obtained from the pinhole tests performed on soil samples amended with aluminum nitrate, lime, and cement suggests that it took a shorter time for the samples to be stabilized with aluminum nitrate compared to the other two amendment materials.



Figure1 Variation of discharge due to soil stabilization, Lime (a and b), Cement (d and c), Aluminum nitrate (e and f)
 
Effect of Texture on Crushability of Carbonate Sand in Northern Coasts of Persian Gulf
Sm Fatemiaghda, H Shahnazari, H Karami, M Talkhablou,
Volume 11, Issue 4 (5-2018)
Abstract
Carbonate soils are different from silicate soils respect to their origination and engineering behavior. Particles of these soils are mainly residual or debris of sea animals or plants with large amount of calcium carbonate. They also may be chemical sedimentation of calcium carbonate over other soil particles in specific region of seas and oceans. The most important characteristic of these soils is the crushability of their aggregates under loading which is mainly due their shape and also small voids inside of them.  Crushability and subsequent volume changes in carbonate soils have caused many engineering problems in some geotechnical structures such as ...../files/site1/files/0Extended_Abstract5.pdf
Effect of crude oil on the dispersivity of fine-grained soils (Case study: soils of Arak Shazand refinery zone)
Ms Roghayeh Hasani, Dr Ebrahim Asghari-Kaljahi, Dr Sina Majidiana,
Volume 18, Issue 2 (9-2024)
Abstract
With the expansion of the petroleum industry and the aging of facilities and pipelines, oil spills are becoming more frequent. In addition to environmental impacts, oil spills can cause changes in the plasticity and dispersivity of soils. To investigate the potential for dispersion in fine-grained soils due to oil leakage, soil samples were collected from the Shazand Refinery area in Arak and mixed with 0, 5, 10, 15, and 20% by weight crude oil. Specimens were prepared at the maximum dry density obtained from the Proctor compaction test and, after curing, pinhole and double hydrometer tests were conducted. The results of the mentioned tests showed that the fine-grained soil tends to disperse with the addition of up to 15% oil, and this dispersion increases with further increases to 20%. Changes in the soil fabric with increasing oil content were investigated using scanning electron microscopy (SEM) images, and the results showed that the dispersion of soil particles increased with increasing oil content.

Evaluation and ranking of rainfall estimation database data, case study: Khuzestan Province, Iran
Mr Mohammad Jafarpour, Mr Arash Adib,
Volume 19, Issue 6 (12-2025)
Abstract
Precipitation is one of the most important climatic variables, and due to its direct role in water resources, agriculture, and human livelihoods, its accurate assessment is of great significance. In recent years, gridded precipitation datasets, including station, satellite, and reanalysis data, have found widespread application due to their easy accessibility, lower cost, suitable spatial coverage, absence of missing data, and long temporal duration; however, examining their accuracy and validity is essential for scientific use. In this study, five precipitation datasets, namely APHRODITE and CRU (raingauge-based), PERSIANN-CDR (a combination of satellite and raingauge), and NCEP CFSR and ERA5 (reanalysis-based), were evaluated using the indicators R², NSE, NRMSE, BIAS, POD, FAR, and CSI, in comparison with data from 9 synoptic stations in the Khuzestan province. Since the number of indicators was large, the TOPSIS multi-criteria decision-making method was used for the final ranking of the datasets at each station. The results indicated that APHRODITE, CRU, and NCEP/CFSR provided the best performance, with APHRODITE exhibiting the highest agreement with observations across all stations; its average indicators were POD=0.756, FAR=0.290, and CSI=0.692. It was also found that some datasets may have lower accuracy in estimating precipitation amounts but demonstrate suitable performance in identifying rainy days. Therefore, the selection of a precipitation dataset should be based on the intended application.
 

Page 1 from 1     

© 2026 CC BY-NC 4.0 | Journal of Engineering Geology

Designed & Developed by : Yektaweb