# Effective porosity

The term effective porosity lacks a single or straightforward definition. Even some of the terms used in its mathematical description ("$V_{cl}$” and “$V_{sh}$”) have multiple definitions. However, it is most commonly considered to represent the porosity of a rock or sediment available to contribute to fluid flow through the rock or sediment, or often in terms of "flow to a borehole". Porosity that is not considered "effective porosity" includes water bound to clay particles (known as bound water) and isolated "vuggy" porosity (vugs not connected to other pores). The effective porosity is of great importance in considering the suitability of rocks or sediments as oil or gas reservoirs, or as aquifers.

## Summary of terms

Fig. 2

Utilising the Eslinger & Pevear concept, the following terms are illustrated in Figure 2.

### Total porosity

The volume of the reservoir rock which is fluid (oil, water, gas) filled, expressed as a percentage or a fraction of the gross (bulk) rock volume.

### Effective porosity $phi_{e1}$

The sum of all the interconnected pore space. In the vast majority of cases, this core analysis and Petroleum Engineering definition of effective porosity equates to total porosity.

### Effective porosity $phi_{e2}$

Effective porosity measured on core samples which are dried in a humidity oven so that clays retain one or two molecular layers of bound water—however, this CBW tends to a minimum and is likely not reservoir representative.

### Effective porosity $phi_{e3}$

Total porosity minus clay-bound water (CBW).

### Effective porosity $phi_{e4}$

Log effective porosity. In essence, total porosity minus shale water, where solid minerals and the volume of shale (Vsh) constitute the matrix (non-effective porosity) and the remaining volume constitutes the effective porosity. For practical purposes, Vsh includes solid clays and the clay-sized and silt-sized fraction of non-clay minerals plus CBW and capillary bound water associated with shale micropores.

### Effective porosity $phi_{e5}$

In a hydrocarbon-bearing reservoir above the transition zone, only that pore space which is filled with hydrocarbons. From the NMR log, this equates to the Free Fluid Index (FFI), in other words, all pore space above the T2 cut-off.

### Effective porosity $phi_{e6}$

The volume of pore space which contains only producible hydrocarbons.

### Clay-bound water (CBW)

The amount of Clay-bound water is determined by the following equation

$ext{CBW} = phi_t cdot ext{SF} cdot ext{Qv}$[5][6]

where $phi_t$ is total porosity, $ext{SF}$ is salinity factor and $ext{Qv}$ is the Cation Exchange Capacity, meq/ml pore space

The salinity factor $ext{SF}$ is calculated as $0.6425 cdot S^{-0.5} + 0.22$ where $S$ the salinity in g/l,

## 

### Office hours

Sunday:     12-1

Monday:     12-1

Tuesday:     10-12

Wednesday: 10-11

You are welcome to contact me by at any time

You  may also contact me via WhatsApp group, ..

Ext. 2524

### Civil Eng. Students

DON'T miss!

As we approaching the second midterm exams..  Get ready and remember our offices are open to answer you . do not hesitate to .contact me if you have difficulties

For CE 370 students : I do apologize for did not attend the extra lab session that proposed to be on Wednesday at 6 am.  Sorry

Good Luck

### Announcements

My Dear Students

.contact me  to sort it out

There will be an orientation session in the midell of this term to help you select your track in Civil and Environmental Engineering

### Event

#### Special Issue

Published Online on January 2016

### Mining Engineering

Mining engineering is an engineering discipline that involves practice, theory, science, technology, and the application of extracting and processing minerals from a naturally occurring environment. Mining engineering also includes processing minerals for additional value.

### Environmental Engineering

Environmental engineers are the technical professionals who identify and design solutions for    environmental problems. Environmental engineers provide safe drinking water, treat and properly dispose of wastes, maintain air quality, control water pollution, and remediate sites contaminated due to spills or improper disposal of hazardous substances. They monitor the quality of the air, water, and land. And, they develop new and improved means to protect the environment.

### Proverb

Actions speak louder than words

### Univeristies

Universities I've worked in

Assuit University (Home University), Egypt

Imperial College, London, UK

King Saud University, KSA

,Majmaah University

### Also visit

https://www.researchgate.net/profile/Sameh_Ahemd

and give me

### Think

How many red balls we need to make balance

### Sports

Egypt vs Tunisia (Handball final)  30/1/2016

### Course 2016/17-1

1. Computer Applications in Surveying  CE 473
2. Surveying 1 CE 370
3. Photogrammetry CE 474
4. Surveying II  CE 371
5. Design I  (round 4) CE 498

Rule #7

### Latest

Member of the Editorial Board: " Journal of Water Resources and Ocean Sciences"  2013

Participating in The Third International Conference on Water, Energy and Environment,(ICWEE) 2015 - American University of Sharjah, UAE 24-26 March 2015 with a Paper and Poster

New article

Recovery of Titania from Waste-Sludge of Majmaah Water Treatment Plant

"Production of Titania Nano-particles from Wast-

Sludge

### Coming soon

Results of M2 CE311

### Student Conference

Participation  in the 6Th Student Conference

With a paper and oral presentation

From the Senior Design Project CE499 -35

See inside, the paper, and presentation

## Surveying  I -  CE 370 - 2016-2017-1

 Power point Sheets Lecture notes Second Midterm Exam Results Model Answer

Student Performance Records

## Surveying II - CE 371 - 2016-2017-1

 Lectures First midterm exam Lab Results

See Inside

Student Performance Records

## CE 473

 Lecturers Power point Sheets Exams + Quizzes Results

### 2015-2016-2 - Photogrammetry  CE474

 Available 0-1-2-3-4 Power point Available Quizzes 2 and 3 with model Answer Quizzes Available Chapter 1,2,3,4,5 Lecture notes Report 1  Cameras Report Y 60 marks Exams

See Inside

Student Performance Records

## Environmental Engineering 1

CE 360: Environmental Engineering 1

37-2

 Y PP0-1-2-3,4 Power point Y 1,2,3,4,5 Chapters Water quality Poster + Climate Change Reports will be announced (Quiz #2 will be using D2L- Online Quizzes Y Quizzez 2,3 and 4 with model answer and results Exams and results

### Engineering Report Writing

GE 306: Engineering Report Writing

### Senior Design 2 - CE 499

Meeting on 14-4-2015

Second Best paper from Senior Design Projects in 2015

Paper title:

### Evaluation of Groundwater Quality Parameters using Multivariate Statistics- a case Study of Majmaah, KSA

Students:

Abdullah A. Alzeer

Husam K. Almubark

Maijd M. Almotairi

### CE 360-Summer Course

Environmental Engineering I

## Welcome to CE360 second Term 2015-2016

### Engineering Practice

Engineering Practice GE 307

### الهيئة الوطنية للاعتماد والتقويم الاكاديمي

See what can you get from Google!! more than translation and locations

### Contact me

Mobile: 00966598311652

### Thank you

Your frequent visit to my website has helped  a lot to get the 2nd place in the university competition in the  year 1434-2013... Thanks very mush and please keep following my work

زيارتكم المتكررة لموقعي ساهمت في حصولي على المركز الثاني لاحسن المواقع الشخصية بجامعة المجمعة ...لكم جميعا خالص شكري وتقديري

## CE 212

 Y from PP0 to PP 6 + PDF Power points Y Midterm #2 + Model Answer + results Exams Y lab 3 Labs Solution of Quiz 4 + Results HW

## CE 311

M2+ model Answer + PP 1-9 = PDF 1-9 all are available

Sheets 2 + 4 with model Answers

Results of M2

### إحصائية الموقع

عدد الصفحات: 1412

البحوث والمحاضرات: 1541

الزيارات: 53327