Magallanes Extensional Structures, Assessment Unit 60590101
0
200
400
600
800
1,000
1,200
1930 1940 1950 1960 1970 1980 1990 2000
DRILLING-COMPLETION YEAR
CU
M. N
EW
-FIE
LD
WIL
DC
AT
WE
LL
S (
No
.)
Magallanes Extensional Structures, Assessment Unit 60590101
0
10
20
30
40
50
60
70
80
1937
1940
1943
1946
1949
1952
1955
1958
1961
1964
1967
1970
1973
1976
1979
1982
1985
1988
1991
1994
DRILLING-COMPLETION YEAR
NE
W-F
IEL
D W
ILD
CA
T W
EL
LS
(N
o.)
Magallanes Extensional Structures, Assessment Unit 60590101
1
10
100
1,000
0 5 10 15 20 25 30
OIL-FIELD RANK BY SIZE
KN
OW
N O
IL-F
IEL
D S
IZE
(M
MB
O)
First third of fields discovered
Second third of fields discovered
Third third of fields discovered
Magallanes Extensional Structures, Assessment Unit 60590101
0
5
10
15
20
25
1 to
<2
2 to
<4
4 to
<8
8 to
<16
16 to
<32
32 to
<64
64 to
<12
8
128
to <
256
256
to <
512
512
to <
1,02
4
1,02
4 to
<2,
048
2,04
8 to
<4,
096
4,09
6 to
<8,
192
8,19
2 to
<16
,384
16,3
84 to
<32
,768
32,7
68 to
<65
,536
65,5
36 to
<13
1,07
2
131,
072
to <
262,
144
>=26
2,14
4
KNOWN OIL-FIELD SIZE (MMBO)
OIL
FIE
LD
S (
No
.)
Third third offieldsdiscovered
Second thirdof fieldsdiscovered
First third offieldsdiscovered
Magallanes Extensional Structures, Assessment Unit 60590101
0
50
100
150
200
250
300
350
1 to
<2
2 to
<4
4 to
<8
8 to
<16
16 to
<32
32 to
<64
64 to
<12
8
128
to <
256
256
to <
512
512
to <
1,02
4
1,02
4 to
<2,
048
2,04
8 to
<4,
096
4,09
6 to
<8,
192
8,19
2 to
<16
,384
16,3
84 to
<32
,768
32,7
68 to
<65
,536
65,5
36 to
<13
1,07
2
131,
072
to <
262,
144
>=26
2,14
4
KNOWN OIL-FIELD SIZE (MMBO)
VO
LU
ME
OF
OIL
(M
MB
O)
Magallanes Extensional Structures, Assessment Unit 60590101
1
10
100
1,000
1930 1940 1950 1960 1970 1980 1990 2000
FIELD-DISCOVERY YEAR
KN
OW
N O
IL-F
IEL
D S
IZE
(M
MB
O)
Magallanes Extensional Structures, Assessment Unit 60590101
1
10
100
1,000
0 200 400 600 800 1,000 1,200
CUM. NEW-FIELD WILDCAT WELLS (No.)
KN
OW
N O
IL-F
IEL
D S
IZE
(M
MB
O)
Magallanes Extensional Structures, Assessment Unit 60590101
0
200
400
600
800
1,000
1,200
1,400
1,600
1930 1940 1950 1960 1970 1980 1990 2000
FIELD-DISCOVERY YEAR
CU
M. K
NO
WN
OIL
VO
LU
ME
(M
MB
O)
Magallanes Extensional Structures, Assessment Unit 60590101
0
200
400
600
800
1,000
1,200
1,400
1,600
0 200 400 600 800 1,000 1,200
CUM. NEW-FIELD WILDCAT WELLS (No.)
CU
M. K
NO
WN
OIL
VO
LU
ME
(M
MB
O)
Magallanes Extensional Structures, Assessment Unit 60590101
0
10
20
30
40
50
60
70
80
90
1930 1940 1950 1960 1970 1980 1990 2000
FIELD-DISCOVERY YEAR
CU
M. O
IL F
IEL
DS
(N
o.)
Magallanes Extensional Structures, Assessment Unit 60590101
0
10
20
30
40
50
60
70
80
90
0 200 400 600 800 1,000 1,200
CUM. NEW-FIELD WILDCAT WELLS (No.)
CU
M. O
IL F
IEL
DS
(N
o.)
Magallanes Extensional Structures, Assessment Unit 60590101
0
500
1,000
1,500
2,000
2,500
3,000
3,500
4,000
1930 1940 1950 1960 1970 1980 1990 2000
FIELD-DISCOVERY YEAR
RE
SE
RV
OIR
DE
PT
H, O
IL F
IEL
DS
(m
)
Magallanes Extensional Structures, Assessment Unit 60590101
0
500
1,000
1,500
2,000
2,500
3,000
3,500
4,000
0 200 400 600 800 1,000 1,200
CUM. NEW-FIELD WILDCAT WELLS (No.)
RE
SE
RV
OIR
DE
PT
H, O
IL F
IEL
DS
(m
)
Magallanes Extensional Structures, Assessment Unit 60590101
0
2,000
4,000
6,000
8,000
10,000
12,000
14,000
16,000
18,000
20,000
0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000
MEAN RESERVOIR DEPTH (m)
GA
S/O
IL, O
IL F
IEL
DS
(C
FG
/BO
)
Magallanes Extensional Structures, Assessment Unit 60590101
0
2
4
6
8
10
12
14
16
18
20
0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000
MEAN RESERVOIR DEPTH (m)
NG
L/G
AS
, OIL
FIE
LD
S (
BN
GL
/MM
CF
G)
Magallanes Extensional Structures, Assessment Unit 60590101
0
5
10
15
20
25
30
35
0 to <10 10 to<20
20 to<30
30 to<40
40 to<50
50 to<60
60 to<70
70 to<80
80 to<90
90 to<100
>=100
API GRAVITY (DEGREES)
RE
SE
RV
OIR
S IN
OIL
FIE
LD
S (
No
.)
Magallanes Extensional Structures, Assessment Unit 60590101
1
10
100
1,000
10,000
0 5 10 15 20
GAS-FIELD RANK BY SIZE
KN
OW
N G
AS
-FIE
LD
SIZ
E (
BC
FG
)
First third of fields discovered
Second third of fields discovered
Third third of fields discovered
Magallanes Extensional Structures, Assessment Unit 60590101
0
2
4
6
8
10
12
14
16
6 to
<12
12 to
<24
24 to
<48
48 to
<96
96 to
<19
2
192
to <
384
384
to <
768
768
to <
1,53
6
1,53
6 to
<3,
072
3,07
2 to
<6,
144
6,14
4 to
<12
,288
12,2
88 to
<24
,576
24,5
76 to
<49
,152
49,1
52 to
<98
,304
98,3
04 to
<19
6,60
8
196,
608
to <
393,
216
393,
216
to <
786,
432
786,
432
to <
1,57
2,86
4
>=1,
572,
864
KNOWN GAS-FIELD SIZE (BCFG)
GA
S F
IEL
DS
(N
o.)
Third third offieldsdiscovered
Second thirdof fieldsdiscovered
First third offieldsdiscovered
Magallanes Extensional Structures, Assessment Unit 60590101
0
1,000
2,000
3,000
4,000
5,000
6,000
6 to
<12
12 to
<24
24 to
<48
48 to
<96
96 to
<19
2
192
to <
384
384
to <
768
768
to <
1,53
6
1,53
6 to
<3,
072
3,07
2 to
<6,
144
6,14
4 to
<12
,288
12,2
88 to
<24
,576
24,5
76 to
<49
,152
49,1
52 to
<98
,304
98,3
04 to
<19
6,60
8
196,
608
to <
393,
216
393,
216
to <
786,
432
786,
432
to <
1,57
2,86
4
>=1,
572,
864
KNOWN GAS-FIELD SIZE (BCFG)
VO
LU
ME
OF
GA
S (
BC
FG
)
Magallanes Extensional Structures, Assessment Unit 60590101
1
10
100
1,000
10,000
1930 1940 1950 1960 1970 1980 1990 2000
FIELD-DISCOVERY YEAR
KN
OW
N G
AS
-FIE
LD
SIZ
E (
BC
FG
)
Magallanes Extensional Structures, Assessment Unit 60590101
1
10
100
1,000
10,000
0 200 400 600 800 1,000 1,200
CUM. NEW-FIELD WILDCAT WELLS (No.)
KN
OW
N G
AS
-FIE
LD
SIZ
E (
BC
FG
)
Magallanes Extensional Structures, Assessment Unit 60590101
0
5,000
10,000
15,000
20,000
25,000
30,000
1930 1940 1950 1960 1970 1980 1990 2000
FIELD-DISCOVERY YEAR
CU
M. K
NO
WN
GA
S V
OL
UM
E (
BC
FG
)
Magallanes Extensional Structures, Assessment Unit 60590101
0
5,000
10,000
15,000
20,000
25,000
30,000
0 200 400 600 800 1,000 1,200
CUM. NEW-FIELD WILDCAT WELLS (No.)
CU
M. K
NO
WN
GA
S V
OL
UM
E (
BC
FG
)
Magallanes Extensional Structures, Assessment Unit 60590101
0
10
20
30
40
50
60
70
1930 1940 1950 1960 1970 1980 1990 2000
FIELD-DISCOVERY YEAR
CU
M. G
AS
FIE
LD
S (
No
.)
Magallanes Extensional Structures, Assessment Unit 60590101
0
10
20
30
40
50
60
70
0 200 400 600 800 1,000 1,200
CUM. NEW-FIELD WILDCAT WELLS (No.)
CU
M. G
AS
FIE
LD
S (
No
.)
Magallanes Extensional Structures, Assessment Unit 60590101
0
500
1,000
1,500
2,000
2,500
3,000
3,500
4,000
1930 1940 1950 1960 1970 1980 1990 2000
FIELD-DISCOVERY YEAR
RE
SE
RV
OIR
DE
PT
H, G
AS
FIE
LD
S (
m)
Magallanes Extensional Structures, Assessment Unit 60590101
0
500
1,000
1,500
2,000
2,500
3,000
3,500
4,000
0 200 400 600 800 1,000 1,200
CUM. NEW-FIELD WILDCAT WELLS (No.)
RE
SE
RV
OIR
DE
PT
H, G
AS
FIE
LD
S (
m)
Magallanes Extensional Structures, Assessment Unit 60590101
0
20
40
60
80
100
120
0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000
MEAN RESERVOIR DEPTH (m)
LIQ
UID
S/G
AS
, GA
S F
IEL
DS
(B
L/M
MC
FG
)
Magallanes Extensional Structures, Assessment Unit 60590101
0
200
400
600
800
1,000
1,200
1930 1940 1950 1960 1970 1980 1990 2000
DRILLING-COMPLETION YEAR
CU
M. N
EW
-FIE
LD
WIL
DC
AT
WE
LL
S (
No
.)
Magallanes Extensional Structures, Assessment Unit 60590101
0
10
20
30
40
50
60
70
80
1937
1940
1943
1946
1949
1952
1955
1958
1961
1964
1967
1970
1973
1976
1979
1982
1985
1988
1991
1994
DRILLING-COMPLETION YEAR
NE
W-F
IEL
D W
ILD
CA
T W
EL
LS
(N
o.)
Magallanes Extensional Structures, Assessment Unit 60590101
1
10
100
1,000
0 5 10 15 20 25 30
OIL-FIELD RANK BY SIZE
GR
OW
N O
IL-F
IEL
D S
IZE
(M
MB
O)
First third of fields discovered
Second third of fields discovered
Third third of fields discovered
Magallanes Extensional Structures, Assessment Unit 60590101
0
2
4
6
8
10
12
14
16
18
20
1 to
<2
2 to
<4
4 to
<8
8 to
<16
16 to
<32
32 to
<64
64 to
<12
8
128
to <
256
256
to <
512
512
to <
1,02
4
1,02
4 to
<2,
048
2,04
8 to
<4,
096
4,09
6 to
<8,
192
8,19
2 to
<16
,384
16,3
84 to
<32
,768
32,7
68 to
<65
,536
65,5
36 to
<13
1,07
2
131,
072
to <
262,
144
>=26
2,14
4
GROWN OIL-FIELD SIZE (MMBO)
OIL
FIE
LD
S (
No
.)
Third third offieldsdiscovered
Second thirdof fieldsdiscovered
First third offieldsdiscovered
Magallanes Extensional Structures, Assessment Unit 60590101
0
50
100
150
200
250
300
350
400
450
1 to
<2
2 to
<4
4 to
<8
8 to
<16
16 to
<32
32 to
<64
64 to
<12
8
128
to <
256
256
to <
512
512
to <
1,02
4
1,02
4 to
<2,
048
2,04
8 to
<4,
096
4,09
6 to
<8,
192
8,19
2 to
<16
,384
16,3
84 to
<32
,768
32,7
68 to
<65
,536
65,5
36 to
<13
1,07
2
131,
072
to <
262,
144
>=26
2,14
4
GROWN OIL-FIELD SIZE (MMBO)
VO
LU
ME
OF
OIL
(M
MB
O)
Magallanes Extensional Structures, Assessment Unit 60590101
1
10
100
1,000
1930 1940 1950 1960 1970 1980 1990 2000
FIELD-DISCOVERY YEAR
GR
OW
N O
IL-F
IEL
D S
IZE
(M
MB
O)
Magallanes Extensional Structures, Assessment Unit 60590101
1
10
100
1,000
0 200 400 600 800 1,000 1,200
CUM. NEW-FIELD WILDCAT WELLS (No.)
GR
OW
N O
IL-F
IEL
D S
IZE
(M
MB
O)
Magallanes Extensional Structures, Assessment Unit 60590101
0
200
400
600
800
1,000
1,200
1,400
1,600
1930 1940 1950 1960 1970 1980 1990 2000
FIELD-DISCOVERY YEAR
CU
M. G
RO
WN
OIL
VO
LU
ME
(M
MB
O)
Magallanes Extensional Structures, Assessment Unit 60590101
0
200
400
600
800
1,000
1,200
1,400
1,600
0 200 400 600 800 1,000 1,200
CUM. NEW-FIELD WILDCAT WELLS (No.)
CU
M. G
RO
WN
OIL
VO
LU
ME
(M
MB
O)
Magallanes Extensional Structures, Assessment Unit 60590101
0
10
20
30
40
50
60
70
80
90
1930 1940 1950 1960 1970 1980 1990 2000
FIELD-DISCOVERY YEAR
CU
M. O
IL F
IEL
DS
(N
o.)
Magallanes Extensional Structures, Assessment Unit 60590101
0
10
20
30
40
50
60
70
80
90
0 200 400 600 800 1,000 1,200
CUM. NEW-FIELD WILDCAT WELLS (No.)
CU
M. O
IL F
IEL
DS
(N
o.)
Magallanes Extensional Structures, Assessment Unit 60590101
0
500
1,000
1,500
2,000
2,500
3,000
3,500
4,000
1930 1940 1950 1960 1970 1980 1990 2000
FIELD-DISCOVERY YEAR
RE
SE
RV
OIR
DE
PT
H, O
IL F
IEL
DS
(m
)
Magallanes Extensional Structures, Assessment Unit 60590101
0
500
1,000
1,500
2,000
2,500
3,000
3,500
4,000
0 200 400 600 800 1,000 1,200
CUM. NEW-FIELD WILDCAT WELLS (No.)
RE
SE
RV
OIR
DE
PT
H, O
IL F
IEL
DS
(m
)
Magallanes Extensional Structures, Assessment Unit 60590101
0
2,000
4,000
6,000
8,000
10,000
12,000
14,000
16,000
18,000
20,000
0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000
MEAN RESERVOIR DEPTH (m)
GA
S/O
IL, O
IL F
IEL
DS
(C
FG
/BO
)
Magallanes Extensional Structures, Assessment Unit 60590101
0
2
4
6
8
10
12
14
16
18
20
0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000
MEAN RESERVOIR DEPTH (m)
NG
L/G
AS
, OIL
FIE
LD
S (
BN
GL
/MM
CF
G)
Magallanes Extensional Structures, Assessment Unit 60590101
0
5
10
15
20
25
30
35
0 to <10 10 to<20
20 to<30
30 to<40
40 to<50
50 to<60
60 to<70
70 to<80
80 to<90
90 to<100
>=100
API GRAVITY (DEGREES)
RE
SE
RV
OIR
S IN
OIL
FIE
LD
S (
No
.)
Magallanes Extensional Structures, Assessment Unit 60590101
1
10
100
1,000
10,000
0 5 10 15 20 25 30
GAS-FIELD RANK BY SIZE
GR
OW
N G
AS
-FIE
LD
SIZ
E (
BC
FG
)
First third of fields discovered
Second third of fields discovered
Third third of fields discovered
Magallanes Extensional Structures, Assessment Unit 60590101
0
2
4
6
8
10
12
14
16
18
20
6 to
<12
12 to
<24
24 to
<48
48 to
<96
96 to
<19
2
192
to <
384
384
to <
768
768
to <
1,53
6
1,53
6 to
<3,
072
3,07
2 to
<6,
144
6,14
4 to
<12
,288
12,2
88 to
<24
,576
24,5
76 to
<49
,152
49,1
52 to
<98
,304
98,3
04 to
<19
6,60
8
196,
608
to <
393,
216
393,
216
to <
786,
432
786,
432
to <
1,57
2,86
4
>=1,
572,
864
GROWN GAS-FIELD SIZE (BCFG)
GA
S F
IEL
DS
(N
o.)
Third third offieldsdiscovered
Second thirdof fieldsdiscovered
First third offieldsdiscovered
Magallanes Extensional Structures, Assessment Unit 60590101
0
2,000
4,000
6,000
8,000
10,000
12,000
6 to
<12
12 to
<24
24 to
<48
48 to
<96
96 to
<19
2
192
to <
384
384
to <
768
768
to <
1,53
6
1,53
6 to
<3,
072
3,07
2 to
<6,
144
6,14
4 to
<12
,288
12,2
88 to
<24
,576
24,5
76 to
<49
,152
49,1
52 to
<98
,304
98,3
04 to
<19
6,60
8
196,
608
to <
393,
216
393,
216
to <
786,
432
786,
432
to <
1,57
2,86
4
>=1,
572,
864
GROWN GAS-FIELD SIZE (BCFG)
VO
LU
ME
OF
GA
S (
BC
FG
)
Magallanes Extensional Structures, Assessment Unit 60590101
1
10
100
1,000
10,000
1930 1940 1950 1960 1970 1980 1990 2000
FIELD-DISCOVERY YEAR
GR
OW
N G
AS
-FIE
LD
SIZ
E (
BC
FG
)
Magallanes Extensional Structures, Assessment Unit 60590101
1
10
100
1,000
10,000
0 200 400 600 800 1,000 1,200
CUM. NEW-FIELD WILDCAT WELLS (No.)
GR
OW
N G
AS
-FIE
LD
SIZ
E (
BC
FG
)
Magallanes Extensional Structures, Assessment Unit 60590101
0
5,000
10,000
15,000
20,000
25,000
30,000
1930 1940 1950 1960 1970 1980 1990 2000
FIELD-DISCOVERY YEAR
CU
M. G
RO
WN
GA
S V
OL
UM
E (
BC
FG
)
Magallanes Extensional Structures, Assessment Unit 60590101
0
5,000
10,000
15,000
20,000
25,000
30,000
0 200 400 600 800 1,000 1,200
CUM. NEW-FIELD WILDCAT WELLS (No.)
CU
M. G
RO
WN
GA
S V
OL
UM
E (
BC
FG
)
Magallanes Extensional Structures, Assessment Unit 60590101
0
10
20
30
40
50
60
70
80
1930 1940 1950 1960 1970 1980 1990 2000
FIELD-DISCOVERY YEAR
CU
M. G
AS
FIE
LD
S (
No
.)
Magallanes Extensional Structures, Assessment Unit 60590101
0
10
20
30
40
50
60
70
80
0 200 400 600 800 1,000 1,200
CUM. NEW-FIELD WILDCAT WELLS (No.)
CU
M. G
AS
FIE
LD
S (
No
.)
Magallanes Extensional Structures, Assessment Unit 60590101
0
500
1,000
1,500
2,000
2,500
3,000
3,500
4,000
1930 1940 1950 1960 1970 1980 1990 2000
FIELD-DISCOVERY YEAR
RE
SE
RV
OIR
DE
PT
H, G
AS
FIE
LD
S (
m)
Magallanes Extensional Structures, Assessment Unit 60590101
0
500
1,000
1,500
2,000
2,500
3,000
3,500
4,000
0 200 400 600 800 1,000 1,200
CUM. NEW-FIELD WILDCAT WELLS (No.)
RE
SE
RV
OIR
DE
PT
H, G
AS
FIE
LD
S (
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Magallanes Extensional Structures, Assessment Unit 60590101
0
20
40
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0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000
MEAN RESERVOIR DEPTH (m)
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Magallanes Extensional Structures, Assessment Unit 60590101Volumes of Discovered Petroleum
[MMBO, million barrels of oil. BCFG, billion cubic feet of gas. MMBNGL, million barrels of natural gas liquids. Fields containing less than 1 MMBO in oilfields or 6 BCFG in gas fields were not considered in the assessment. Fields were classified as oil or gas by the USGS. Fields without reported discoverydates were not included. NA means not applicable and is shown for volumes where only one field is present. Calculated values may not be equal to the
sums of the component values because numbers have been independently rounded.]
Known (Discovered) Volumes Grown (Discovered) VolumesField Type Number Number
of Fields Oil (MMBO) Gas (BCFG) NGL (MMBNGL) of Fields Oil (MMBO) Gas (BCFG) NGL (MMBNGL)
Oil Fields 77 946 7,203 33 83 1,475 10,402 49Gas Fields 60 250 17,436 177 69 338 24,202 250
Fields <1 MMBOE 107 20 99 1 92 23 77 1
All Fields 244 1,216 24,739 211 244 1,835 34,681 300
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Magallanes Extensional Structures, Assessment Unit 60590101Discovery-History Sequence
[MMBO, million barrels of oil. BCFG, billion cubic feet of gas. Fields containing less than 1 MMBO in oil fields or 6 BCFG in gas fields werenot considered in the assessment. Fields were classified as oil or gas by the USGS. The first half or third shows year of first field discovery
as well as end of period. NA means not applicable and is shown where fewer than four fields are present.]
Discovery-History Sequence - Known (Discovered) VolumesFieldType Year Number of Total Mean Median
(End of Period) Fields Volume Size Size
Oil Fields Known Sizes (MMBO)First third 1945-1969 26 216 8 4Second third 1983 26 558 21 5Third third 1995 25 171 7 2
All Oil Fields 77 946 12 4Gas Fields Known Sizes (BCFG)
First third 1950-1966 20 11,034 552 201Second third 1982 20 1,639 82 37Third third 1995 20 4,763 238 30
All Gas Fields 60 17,436 291 44
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Magallanes Extensional Structures, Assessment Unit 60590101Discovery-History Sequence
[MMBO, million barrels of oil. BCFG, billion cubic feet of gas. Fields containing less than 1 MMBO in oil fields or 6 BCFG in gas fields werenot considered in the assessment. Fields were classified as oil or gas by the USGS. The first half or third shows year of first field discovery
as well as end of period. NA means not applicable and is shown where fewer than four fields are present.]
Discovery-History Sequence - Grown (Discovered) VolumesFieldType Year Number of Total Mean Median
(End of Period) Fields Volume Size Size
Oil Fields Grown Sizes (MMBO)First third 1945-1971 28 515 18 5Second third 1984 28 632 23 8Third third 1995 27 328 12 3
All Oil Fields 83 1,475 18 5Gas Fields Grown Sizes (BCFG)
First third 1950-1967 23 14,291 621 100Second third 1983 23 8,389 365 53Third third 1995 23 1,522 66 41
All Gas Fields 69 24,202 351 53
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