نفت به‌عنوان یکی از منابع اصلی درآمدی کشور، نقش قابل ‌توجهی بر تحولات فضایی شهرها داشته است. بندر ماهشهر هم به‌عنوان یکی از شهرهای استان خوزستان از این قاعده مستثنی نیست. از این‌ رو به دلیل نزدیکی به معادن نفت و گاز تحت تأثیر این صنعت (صنعت نفت) قرار گرفته است. گسترش کالبدی- فضایی بندر ماهشهر در مدتی کوتاه متأثر از استقرار حجم عظیمی از صنایع و پتروشیمی ها، سبب افزایش مهاجرپذیری و گسترش ساخت‌وسازهای بی سابقه ای گردید. لذا مسئله اساسی پژوهش حاضر: تحلیلی بر نقش اقتصاد نفتی در تحولات فضایی بندر ماهشهر می باشد. با توجه نقش قابل توجه نفت در تحولات فضایی شهرها، این پژوهش با هدف ارزیابی روند تحولات فضایی بندر ماهشهر در ادوار مختلف انجام شده است. روش پژوهش توصیفی- تحلیلی و از نظر هدف گذاری كاربردي است. در اين پژوهش با توجه به مطالعات طرح‌های جامع و تفصیلی، عکس‌های هوایی موجود و استفاده از نرم افزار هایGoogle Earth و Arc/Gis10.8 به ارزیابی روند تحولات فضایی بندر ماهشهر طی سال های 1309 تا 1401 پرداخته شد. یافته ها حاکی از آن است که نفت، نقش قابل ‌توجهی بر تحولات فضایی بندر ماهشهر داشته است و بیشترین فعالیت‌های اقتصادی و اجتماعی در این شهر به دلیل وابستگی به صنعت نفت صورت گرفته است. بنابراین، سود و زیانی که از فعالیت این صنعت به دست می‌آید، نقش مهمی در تحولات فضایی این شهر داشته است. نتایج این پژوهش نشان داد تا سال 1309 روند تحولات فضایی بندر ماهشهر شامل بخش ماهشهر قدیم و بخش ناحیه صنعتی بوده است و این شهر طی سال‌های 1364 تا 1386 با بیشترین روند تحولات فضایی در محدوده طرح تفصیلی با مساحتی برابر 04/731 هکتار و در خارج از محدوده طرح تفصیلی با مساحتی برابر 16/686 هکتار در شمال غرب، جنوب، غرب و جنوب غرب همراه بوده است. تفاصيل المقالة

Abadan plain is considered as the one of the hydrocarbon sub basins in south of Zagros in Iran which from the tectonic viewpoint is known as the Arabian plate north platform terminal. Existence of basic differences in Abadan plain sediments due to the structural geological viewpoint with Zagros sediments area and Dezful embayment shows the petro physical studies necessary. So for determination of porosity, shale volume and water formation saturation from important rank factors after the determination by the probes and data sending and their processing as the full set logs, related data was prepared as the diagrams and then determination and evaluation was performed by two certain and probable methods. As it is observed in Sarvak Formation interval, the results showed that major lithology was carbonate and also observed with Dolomite rocks in the depth of 3250-3575 and 3450-3475 m. From the oil reservoir viewpoint, 3125-3265 m is the best hydrocarbon depth in wells, though beside oil zone, free water zone is present but due to the 30% water saturate sub limit can almost have more oil reservoir. But due to the very low quality, next predicts for depth less than 3125 and 3240 m till the Sarvak interval ending has no certainty. تفاصيل المقالة

In the oil province of southern Iran like other hydrocarbon zones, thorough understanding and risk management resulting from the rock mass deformation, can be of great help in executing operational processes such as the stabilization of the borehole wall, controlling the sand production in the borehole and hydraulic fracture. In oil well excavation operations, determining maximum and minimum horizontal stresses helps in designing the excavation route in the minimum stress direction so that collapsing of the borehole wall and drilling tube blockage against the rocks is avoided. The aim of this study was removing the main excavation problems especially of the diversion wells through exact geomechanical calculations in the Darian lime formation depth range in the understudy field. In order to develop the geomechanical model, first the bulk, the shear and the Young's modules, the Poisson coefficient and Vp/Vs ratio were calculated using the visual log data integrated with the geomechanical parameters, and the strength parameters like uniaxial compressive strength, internal friction coefficient and tensile strengths and static modulus of elasticity were determined and then the determination of direction and min/max horizontal stresses alongside the formation thickness were studied. In the end by the assessment of the geomechanical model and calculating the mud weight during drilling of the understudy well, and using the STAB View software output, the mud weight window of 80-120 PCF and the drilling Azimuth range of 30°- 45° was recommended for the prevention of borehole wall collapse for Darian formation. تفاصيل المقالة

From these factors the tunnel form, dimensions, depth, the tunnel drilling method, presence of water, etc. can be mentioned. Achieving an optimized design requires identification of effective parameters and the relationships among them. Effective design parameters include stability of the tunnel face, horizontal and vertical displacement, seismic wave, and shrinkage phenomenon, etc. Also considering the importance of the structural stability on the ground surface above the tunnel, especially in the urban tunnels, the settlement level of the ground surface must be considered. In this study the stability of an 8m width and height horseshoe sectioned tunnel located in Tehran alluvium having been projected for water transmission has been technically analyzed using the FLAC 2D software and the comparison wad made using empirical and analytical methods. The results showed that the maximum settlement resulting from design step using software is 14.9 mm which is almost consistent with the value obtained from the empirical relationship, and the difference estimation lies within the acceptable range (0.7%). Also the obtained horizontal displacement shows that the maximum displacement within the 25m distance from the tunnel axis (on both sides) is 2mm and the values obtained from the empirical relationship showed that the maximum horizontal displacement occurs on the 25m distance from the tunnel axis. تفاصيل المقالة