application of different inverse methods for combination of vs and vgpr data to estimate porosity and water saturation

نویسندگان

ramin varfinezhad

m.sc. graduate, department of earth physics, institute of geophysics, university of tehran, iran mohamd kazem hafizi

professor, department of earth physics, institute of geophysics, university of tehran, iran hosein hashemi

assistant professor, department of earth physics, institute of geophysics, university of tehran, iran

چکیده

inverse problem is one of the most important problems in geophysics as model parameters can be estimated from the measured data directly using inverse techniques. in this paper, applying different inverse methods on integration of s-wave and gpr velocities are investigated for estimation of porosity and water saturation. a combination of linear and nonlinear inverse problems are solved. linear least-squares and conjugate gradient are used as linear techniques, whereas grid search and newton methods are selected as nonlinear ones. it is understood that vs depends on density and lame constant (shear modulus) and vgpr on dielectric constant. this combination seems to be logical. shear modulus is related to porosity using bruggeman’s rule. density and dielectric constant is also related to porosity and water saturation. this implies that vs and vgpr are bivariate functions of porosity and water saturation, which are our unknown model parameters. the model parameters are estimated to minimize the cost functional ora system of the equations. in order to convert the nonlinear problem into the linear form, taking logarithm and changing variables were used. the problem was convex, which was inferred from the linear form, so there was just one local minimum as the global minimum of the problem. the grid search method shows that porosity and water saturation cannot be estimated by vgpr or vs uniquely. the results of the four methods were compared with each other and a good agreement was observed.

برای دانلود باید عضویت طلایی داشته باشید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Application of different inverse methods for combination of vS and vGPR data to estimate porosity and water saturation

Inverse problem is one of the most important problems in geophysics as model parameters can be estimated from the measured data directly using inverse techniques. In this paper, applying different inverse methods on integration of S-wave and GPR velocities are investigated for estimation of porosity and water saturation. A combination of linear and nonlinear inverse problems are solved. Linear ...

متن کامل

the innovation of a statistical model to estimate dependable rainfall (dr) and develop it for determination and classification of drought and wet years of iran

آب حاصل از بارش منبع تأمین نیازهای بی شمار جانداران به ویژه انسان است و هرگونه کاهش در کم و کیف آن مستقیماً حیات موجودات زنده را تحت تأثیر منفی قرار می دهد. نوسان سال به سال بارش از ویژگی های اساسی و بسیار مهم بارش های سالانه ایران محسوب می شود که آثار زیان بار آن در تمام عرصه های اقتصادی، اجتماعی و حتی سیاسی- امنیتی به نحوی منعکس می شود. چون میزان آب ناشی از بارش یکی از مولفه های اصلی برنامه ...

15 صفحه اول

development of different optical methods for determination of glucose using cadmium telluride quantum dots and silver nanoparticles

a simple, rapid and low-cost scanner spectroscopy method for the glucose determination by utilizing glucose oxidase and cdte/tga quantum dots as chromoionophore has been described. the detection was based on the combination of the glucose enzymatic reaction and the quenching effect of h2o2 on the cdte quantum dots (qds) photoluminescence.in this study glucose was determined by utilizing glucose...

construction and validation of translation metacognitive strategy questionnaire and its application to translation quality

like any other learning activity, translation is a problem solving activity which involves executing parallel cognitive processes. the ability to think about these higher processes, plan, organize, monitor and evaluate the most influential executive cognitive processes is what flavell (1975) called “metacognition” which encompasses raising awareness of mental processes as well as using effectiv...

comparative dna interaction studies of antiviral drug, zidovudine and its complex using different instrumental methods

هدف از این مطالعه بررسی امکان استفاده از داروهای شناخته شده در درمان سایر بیماریها به عنوان داروهای ضد سرطان است. همچنین با استفاده از این داروها در ساختمان کمپلکس فلز می توان شاخص های دارویی بدست آمده را بررسی نمود. داروی ضد ویروس ایدز(hiv)به نام زیدوودین(azt)انتخاب و.کمپلکس.محلول.در.آب[pt(azt)2]cl2سنتزو به روشهای مختلف فیزیکی و شیمیایی شناسایی گردید. بر هم کنش مقایسه ای این دارو و کمپلکس پلا...

15 صفحه اول

simulation and experimental studies for prediction mineral scale formation in oil field during mixing of injection and formation water

abstract: mineral scaling in oil and gas production equipment is one of the most important problem that occurs while water injection and it has been recognized to be a major operational problem. the incompatibility between injected and formation waters may result in inorganic scale precipitation in the equipment and reservoir and then reduction of oil production rate and water injection rate. ...

منابع من

با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید


عنوان ژورنال:
فیزیک زمین و فضا

جلد ۴۱، شماره ۴، صفحات ۸۹-۹۴

میزبانی شده توسط پلتفرم ابری doprax.com

copyright © 2015-2023