Welcome to Petroleum Geology Forums

This is a free online community that aims to bring petroleum professionals and geologists together and share valuable knowledge. Registration is easy so become a member now for instant free access.
  • Petroleum Geologists can stay up to date with industry related topics and exchange ideas and concepts.
  • Upstream Oil and Gas Consultants get a chance to share their expertise and gain exposure to land future projects.
  • Geology students and graduates can join the discussion and get into contact with potential future employees.

  >> Register Now





Post new topic Reply to topic  [ 2 posts ] 
NTG and water cutoff 
Author Message

Joined: Wed Jun 09, 2010 9:37 pm
Posts: 6
Post NTG and water cutoff
Hey there,

Could anybody please tell me how to determine the porosity and water saturation cut-offs in a reservoir? I need to calculate NTG and need to input these cut-offs.

Thanks,

Faisal


Wed Jun 09, 2010 9:39 pm

Joined: Wed Jun 09, 2010 11:49 pm
Posts: 6
Post Re: NTG and water cutoff
faisal,

Different formation have different Porosity and Water Saturation cut-offs. They are usually decided upon after getting some production data from nearest field. Sometimes very low porosity can still results in production, particularly when producing a gas field.

Usually however, in case of a sandstone reservoir the Shale Volume cut-off is 35%, the Water Saturation cutoff is 50-60% and the Porosity cut-off of 3-5% are used. This can act as a base for initial calculations, but needs to be re-evaluated on a case to case basis.

Cut-offs are very important for calculating the Net-Pay and usually follow from interpreting electric logs (resisitivity usually). No software is available and it is mainly based on the interpreters vision and experience. When starting of it is some times good to change the parameters and see the effect is on the N:G ratio.

Regards

Muhammed


Fri Jun 18, 2010 3:58 pm
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 2 posts ] 


Related topics 
 Topics   Author   Replies   Views   Last post 
There are no new unread posts for this topic. NTG OR N/G: Defining Net Cut-offs

ContentPoster

0

8208

Mon Nov 10, 2014 9:18 pm

ContentPoster View the latest post

 



Search for:
Jump to:  
cron


Content on EPGeology.com is intended for personal use only and to supplement, not replace, professional judgment. EPGeology.com disclaims any and all liability for your use of its content. As most of our content is supplied by our users we can not check copyright, and stress that copyright remains at the original owner. If you suspect copyright infringement please use the contact form to report it.
Contact || © EPGeology.com. || Powered by phpBB Asteroid Mining

phpBB SEO