Soil is one of the most important resources in nay country and its degradation causes great losses for human beings, specially in arid and semi- arid regions. One of the existing views in watershed is a kind of management based on the analysis of a set of factors influencing watershed basin as a unit of soil and water resources. Geographical Investigation System (GIS) is used as an efficient means in evaluating and solving of many Problems of natural resources. In this connection, the rate of erosion and sediment yield of Kordshikh river, located in 20 Km west of Qir in Fars province, was studied using experimental models of MPSIAC, EPM and Fournier. In MPSIAC model the effect of nine important factors on soil erosion and sediment yield (surface geology, soil, climate, run off, topography, land cover, land use, present erosion condition and channel erosion) was evaluated and numerical values were assigned to them in terms of intensity and weakness of each factor. Using the sum of those values through equation Qs=38.77e0.0353R, where Qs is specific sediment (m3/ km2. yr) and R is sediment yield score, the rate of sediment yield of the basin was measured. The measured Qs for Kordshikh river was Qs= 533.67. In EPM method four coefficients (basin erosion, land use, soil sensitivity to erosion and basin mean dip) were investigated in constructed network in the map. Specific sediment rate in the basin using this method was Gsp=248.94 (m3/km2.yr). In Fournier model, Qs, the rate of specific sediment, was obtained using his first method (log Qs=2.65 log pw2/pa 0.46 log H (tan S) - 1.56) was Qs=207.91 (m3/km2.yr). پرونده مقاله

حوضهی آبریز رودخانهی قره آغاج از سرچشمه تا مقطع کوار دارای وسعتی در حدود 1600 کیلومتر مربع بوده و در این فاصله از جنوب باختری تا جنوب خاوری شیراز جریان دارد . در این تحقیق بار کل رسوب رودخانه ی قره آغاج تا مقطع یادشده با استفاده از خصوصیات هیدرولیکی و رسوب شناسی محاسبه شده است . این خصوصیات شامل عمق جریان، شیب کانال رودخانه، عرض رودخانه، سرعت جریان آب، آبدهی، زاویه ی قرار ذرات رسوبی و اندازه ی مشخّصه ی ذرات (d10، d30، d60و d90) هستند . به علاوه، با اندازه گیری دمای آب رودخانه، لزجت کینماتیکی آب به واسطه ی تأثیر آن در حرکت مواد رسوبی مشخّص شده است . نرخ بار معلّ ق رودخانه با استفاده از روش پیشنهادی یانگ ( 765040 تن در سال) برآورد شده است . این تحقیق نشان می دهد که میزان بار بستر براساس روش میر-پیتر و مولر حدود 21 درصد بار معلّق رودخانه را تشکیل می دهد. پرونده مقاله

The Upper Cretaceous Gurpi and Lower Tertiary Pabdeh formations as units of Folded Zagros were studied in three different regions (Tang-e-Abolhayat, Tang-e-Zanjiran and Maharloo) in Fars Province. Gurpi Formation consists of thin to medium bedded gray marl and marlstone interbedded with thin layers of argillaceous limestone and shale. The dominant Microfacies in this Formation are biomicrite; Index species of Globotruncana give the age of the Formation from Lower Campanian to Upper Maastrichtian. Pabdeh Formation consists of bluish gray, thin to medium bedded shale and marl and interlayers of argillaceous limestones (with purple shales and thin cherty beds) at lower part, dark gray shales and marls with interlayers of argillaceous limestone in the middle, and alternative layers of thinly bedded argillaceous limestone, shale and marl at the upper part. The dominant Microfacies are biomicrite. Index species of Globorotalia and Hantkenina give the age of Formation from Upper Paleocene to Eocene. The sedimentary environment of both formations is a bathymetrical carbonate floored basin (deep shelf or basin margin) which has deposited its facies in transgressive stage. The contact between the two formations is disconform. In Tang-e-Abolhayat it lies at the base of purple shale. In this region and also in Tang-e-Zanjiran and Maharloo, in addition to the recognition of Globorotalia velascoensis, which is attributed to lower part of the Pabdeh Formation, a glauconitic-Phosphatic bed separates the two formations. This bed represents a non-depositional (epirogeny) period from the Late Maastrichtian to the end of Early Paleocene. پرونده مقاله