Petrophysics MSc Course Notes
Introduction
1.
INTRODUCTION TO PETROPHYSICS AND FORMATION
EVALUATION
1.1
Introduction
The search or economic accumulations of oil and gas starts with the recognition of likely geological
provinces, progresses to seismic surv

Petrophysics MSc Course Notes
14.
The Litho-Density Log
THE LITHO-DENSITY LOG
14.1 Introduction
The litho-density log is a new form of the formation density log with added features. It is typified by
Schlumbergers Litho-Density Tool (LDT). These tools hav

A METHOD for NEUTRON DERIVED POROSITY
DETERMINATION for THIN BEDS
J . M. EDWARDS
A.
1. SIMPSON
ABSTRACT
T he application o f the Scintillotneter t o rudioactivrty
s urveys in boreholes o f oil wells has m ade it possible to
determine bed rhickness w ith a

John H. Doveton
Kansas Geological Survey
C
0 Doveton
1 999
CONTENTS
Resistivity logging
Induction
Laterolog
Vertical resolution and radius of investigation
Porosity logging
Density log
Neutron log
Neutron - density log combination
Primary and secondary po

POROSITY LOGGING
The porosity of a zone can be estimated either from a single porosity log
(sonic, density, neutron, or magnetic resonance log) or a combination of porosity
logs, in order to correct for variable lithology effects in complex reservoirs. In

TEMPERATURE AND WATER RESISTIVITY
For shale-free formations, the conduction of electrical current is almost
entirely carried by ions in the formation water. Quantitative calculations of oil or gas
saturation are therefore predicated on a knowledge of the

DIGITAL LOG DATA
Log analysis calculations used to be done mostly with slide-rules and
charts (pre-1972), then with calculators, and now increasingly with computers.
The digital data for computations are recorded by the logging truck and are
made availabl

Question 4.4
Question
This problem is similar to example 4.4
For 2 segment case divide the well into two segments
For
Treat the middle of the well as the bottom hole and
Treat
divide the upper segment into two and apply the
method
method
Calculate the FP

Petrophysics MSc Course Notes
13.
Formation Density Log
THE FORMATION DENSITY LOG
13.1 Introduction
The formation density log measures the bulk density of the formation. Its main use is to derive a value
for the total porosity of the formation. It s also

Petrophysics MSc Course Notes
12.
Spectral Gamma Ray Log
THE SPECTRAL GAMMA RAY LOG
12.1 Introduction
The spectral gamma ray log measures the natural gamma
radiation emanating from a formation split into
contributions from each of the major radio-isotopic

Petrophysics MSc Course Notes
2.
POROSITY
2.1
Porosity
Theory
The porosity of a rock is the fraction of the volume of space between the solid particles of the rock to
the total rock volume. The space includes all pores, cracks, vugs, inter- and intra-crys

Petrophysics MSc Course Notes
3.
PERMEABILITY
3.1
Permeability
Theory
The permeability of a rock is a measure of the ease with which the rock will permit the passage of
fluids.
The fundamental physical law which governs this is called the Navier-Stokes eq

Petrophysics MSc Course Notes
Fluid Saturation and Capillary Pressure
4.
FLUID SATURATION AND CAPILLARY PRESSURE
4.1
Fluid Saturations
We have seen that the viability of a reservoir depends upon three critical parameters. The first two of
these are the po

Petrophysics MSc Course Notes
5.
WIRELINE LOGGING
5.1
Wireline Logging
What is a Wireline Log
A log is a continuous recording of a
geophysical parameter along a borehole.
Wireline logging is a conventional form of
logging that employs a measurement tool
s

Petrophysics MSc Course Notes
The Borehole Environment
6.
THE BOREHOLE ENVIRONMENT
6.1
Introduction
Wireline logging has a single clearly defined purpose: to give accurate and representative data on the
physical properties of the rock formations and fluid

Petrophysics MSc Course Notes
Fluid Testing and Pressure Logs
7.
FLUID TESTING AND PRESSURE LOGS
7.1
Introduction
Formation fluid testing involves taking fluid samples from the formation and measuring their
pressures. It gives information on the types and

Petrophysics MSc Course Notes
8.
TEMPERATURE LOGS
8.1
Temperature Logs
Introduction
The Temperature Log is a tool for measuring the borehole temperature. Temperature sensors are
attached to every tool combination that is run in a well for the measurement

Petrophysics MSc Course Notes
9.
CALIPER LOGS
9.1
Caliper Logs
Introduction
The Caliper Log is a tool for measuring the diameter
and shape of a borehole. It uses a tool which has 2, 4,
or more extendable arms. The arms can move in and
out as the tool is w

Petrophysics MSc Course Notes
10.
Radioactivity Logging
RADIOACTIVITY LOGGING
10.1 Introduction
Radioactivity is used in several different types of logging tool. There are those that measure the natural
radiation generated by the formation, such as the to

Petrophysics MSc Course Notes
11.
Total Gamma Ray Log
THE TOTAL GAMMA RAY LOG
11.1 Introduction
The gamma ray log measures the total natural gamma radiation emanating from a formation. This
gamma radiation originates from potassium-40 and the isotopes of