شبيه ساز چاه نگاري به روش تشديد مغناطيس هسته اي

در این تحقیق، تحلیل نمودارهای بدست آمده به روش تشدید مغناطیسی هسته ای NMR Well Logging مورد ارزیابی و بررسی قرارگرفته است. این تحلیل و بررسی، توسط نرم افزارهای Matlab ، Fortran ، Excel و Logic انجام گرفته است. به منظور ارزیابی این روش، نخست سیگنال شبیه سازی شده و در نهایت از سیگنال بدست آمده از یك چاه، توسط دستگاه نمودارگیری به روش تشدید مغناطیس هستهای استفاده گردیده است. حاصل این تحقق نرم افزاری است به نام LogIran كه توسط آن می توان نمودارهای NMR را شبیه سازی و بررسی نمود. همچنین در این تحقیق به ارتباط بین تراوایی، تخلخل و نوع هیدروكربورهای درون سازند مخازن با سیگنالهای MRI و تكنولوژی بكار رفته در این دستگاه پی بردیم، كه از روی آن میتوان اولین دستگاه نمودارگیری به طریق تشدید مغناطیس هسته ای را در داخل كشور ساخت .

The purpose of nuclear magnetic resonace well logging is to measure some petrophysical properties of oil reservoirs such as porosity, permeability and hydrocarbon-typing. Nuclear magnetic resonance well logging in comparision with conventional logging methods such as neutron, resistivity and gamma is the only logging methods which is capable of measuring above mentioned petrophysical properties directly and without hazardous which some methods like neutron or gamm has. For these reasons and the capability of this method to logg while drilling it has been an attractive subject for many oil and gas companies and oil drilling research centers. In this study we introduce a software by fortran programming as LogIran for analyzing noisy NMR data which is achieved by nuclear magnetic resonance well logging tools, and transforming these data through an inverse procedure to T2 distribution for determining porosity, permeability and hydrocarbon-types. First we simulate the NMR signals by Matlab software based on different petrophysical parameters, and then by adding noise to signal in the range of 90db to 0.1db which is the worst condition for NMR well logging tools, and measure the capability of software to find T2 distribution and it’s accuracy. For evaluating the ability of the softaware in analyzing real data, we use an NMR log which has been recorded by Shelumberger company in iran. Our outputs in different depths of well were same. As well we campared our results with LogIc software and this adavance software confirmed our procedure too. These results shows that this software can be used as an analyzing software for analyzing high noisy NMR signals and other usage which we need to find T2 distribution like MRI in medical applications and so