01.0

1.1

0.9

0.8

0.7

0.6

0.5

0.4

0.3

0.251.1

1.0

0.9

1.01.05

1.05

1.11.2

1.3

1.4

1.5

1.6 1.7

1.8 1.9

2.0 2.2

2.4

2.63.0

3.02.8

1.21.3

1.1

1.10.95

1.7

1.6

1.5

1.4

1.3

1.2

1.1

1.0

0.9

1 2 3 4 5 6 7 8

7 8 9 10 11 12 13 14 15

Compressibility of Natural Gases(Jan. 1, 1941)

Compressibility Factors for Natural Gases as aFunction of Pseudoreduced Pressure and Temperature.

Com

pres

sibilit

y Fa

ctor

, z

Pseudo Reduced Temperature

Pseudo Reduced Pressure, Pr

3.02.82.62.42.22.01.91.81.71.6

1.51.45

1.351.4

1.3

1.25

1.2

1.15

1.1

2.6 2.42.22.0 1.9

1.71.6 1.4

1.3

1.21.1

1.05

1.051.8

1.4

1.5

Pseudo Reduced Pressure, Pr

A BC D E

Pore Space Not Occupied by Mercury

Air/Mercury Capillary Pressure CurvesCa

pilla

ry P

ress

ure

(psi)

150

100

50

0 10 20 30 40 50 60 70 80 90 100

k(md) 55 25 5 0.05 0.01

(%) 15 10 10 5 5h(ft)

AA

A

B

C

D

E

Top ofReservoir

100% Sw in Rock TypeA Found at This Level

h (ft) Scale 2cm = 10ftRock Type

FWL0

0

20

20

40

40

60

60

80

80

100

100

Oil Saturation

Water Saturation

PHY

SIC

AL

PRO

PER

TIE

S O

F TH

E PA

RA

FFIN

HY

DR

OC

AR

BON

S &

MIS

CEL

LAN

EOU

S C

OM

P OU

ND

S

CO

MPO

UN

DM

OLE

CU

LAR

WEI

GH

T

BO

ILIN

GPO

INT

AT

14.7

PSIA

CR

ITIC

AL

CO

NST

AN

TSLI

QUID

D

ENSI

TY60

_F,

14

.7

PSIA

GA

S D

ENSI

TY60

_F,

14.7

PSIA

(PER

FECT

GA

S)CU

FT

GA

SPE

RG

ALL

ON

_F

PRES

SUR

EPS

IATE

MP

_R

Gm

.

PER

cc

POU

ND

SPE

RCU

FT

POU

ND

SPE

RW

CF

CU

FT

GA

SPE

RG

ALL

ON

LIQU

ID

LIQU

ID(A

CTU

AL)

MET

HA

NE

16.04

25

8.7

673

344

42.27

ETH

AN

E30

.07

12

7.5

709

550

79.23

PRO

PAN

E44

.09

43

.7

518

666

0.50

7231

.66

116.

1936

.35

35.78

ISO

-B

UTA

NE

58.12

10.9

530

733

0.56

2535

.12

153.

1530

.59

29.70

M-B

UTA

NE

58.12

31.1

551

766

0.58

3836

.43

153.

1531

.75

30.77

ISO

-PEN

TAN

E72

.15

82.1

482

830

0.62

4138

.96

190.

1127

.38

26.17

M-P

ENTA

NE

72.15

96.9

485

847

0.83

0539

.36

190.

1127

.83

26.36

M-H

EXA

NE

86.17

155.

743

491

50.

8837

41.43

227.

0724

.34

22.83

M-H

EPTA

NE

100.

220

9.2

397

973

0.88

7542

.92

264.

0321

.89

19.95

M-O

CTA

NE

114.

225

8.2

370

1025

0.70

8244

.09

300.

9919

.55

17.77

M-N

ON

AN

E12

8.3

303.

433

510

730.

7211

48.02

337.

9517

.78

15.88

N-D

ECA

NE

142.

334

5.2

312

1115

0.73

3344

.78

374.

9118

.30

14.30

AIR

28.97

31

7.7

547

239

NIT

RO

GEN

28.02

32

0.4

492

227

OX

YG

EN32

.00

29

7.4

732

278

CA

RB

ON

DIO

XID

E44

.01

10

9.3

1072

548

HY

DRO

GEN

SULP

HID

E34

.08

76

.5

1306

673

WA

TER

18.0

221

2.0

3206

1165

0.99

9162

.37

Qt

tD

reD = 2.5

reD = 3.5

reD = 2.0

reD = 1.5

reD = 4.0reD =

00

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

1.0 2.0 3.0 4.0 5.0 6.0 7.0

r eD=

3.0

reD =6.0

reD = 3.0

reD = 3.5

reD = 4.0

reD = 4.5

reD = 5.0

reD = 7.0reD = 8.0reD =

tD

0 10 20 30 40 50 60 70

Qt

2

0

4

6

8

10

12

14

16

18

20

tD

0

0

10

20

30

40

50

60

70

80

90

100

110

20 40 60 80 120100 140 160 180 200 220 240 260 280 300

reD = 5.0

reD = 6.0

reD = 7.0

reD = 8.0

reD = 9.0

reD = 10.0r e

D=

Qt

10-1

10-1

10-2

2

22

2

2 4

44

4

6 4 6

66

6

8

88

8

8 1.0

1.0

10

10

t D

Q t

r eD

= 3

.0r e

D =

2.5

r eD

= 2

.0

r eD

= 1

.5

r eD

= 3

.5r e

D =

4.0

r eD

= 4

.5r e

D =

5.0

r eD

= 6

.0r e

D =

FIN

ITE

LIN

EAR

AQU

IFER

110

2

102

10

2

22

2

2 4

44

4

6 4 6

66

6

8

88

8

8 10

103

103

102

104

t D

WD

10

reD

=

reD

=(c

ont'd) r e

D =

3.0

r eD

= 2

.5

r eD

= 7

.0r e

D =

8.0

r eD

= 9

.0r e

D =

10.

0

r eD

= 1

5.0

r eD

= 3

.5

r eD

= 4

.0r e

D =

4.5

r eD

= 5

.0

r eD

= 6

.0

USE THIS SCALE FOR LINE(CONT'D) ONLY reD =