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Micropaleontology of Selected Wells and Seismic Shot Holes, Northern Alaska
By Michael B. Mickey1, Hideyo Haga1, and Kenneth J. Bird2 Open-File Report 2006-1055 U.S. Department of the Interior U.S. Geological Survey ______________________________________________________________________ 1. Micropaleo Consultants, Encinitas, California 2. U.S. Geological Survey, Menlo Park, California
U.S. Department of the Interior Gale A. Norton, Secretary
U.S. Geological Survey P. Patrick Leahy, Acting Director
U.S. Geological Survey, Menlo Park, California 2006
For product and ordering information: World Wide Web: http://www.usgs.gov/pubprod Telephone: 1-888-ASK-USGS
For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment: World Wide Web: http://www.usgs.gov Telephone: 1-888-ASK-USGS
Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Although this report is in the public domain, permission must be secured from the individual copyright owners to reproduce any copyrighted material contained within this report.
Contents Introduction and Summary Background Current Study Distribution Charts Data Sheets Diversity Graphs Reports Seismic Shot Hole Samples Acknowledgements References Cited Figures
1. Map showing locations of wells and correlation sections 2. Map showing seismic line and shot hole locations 3. Microfossil zonation scheme, stratigraphy, and ages Well folder: Charts of microfossil abundance for each of 49 wells Well folder: Graphs of microfossil diversity for each of 49 wells
Tables
1. Summary listing of wells and seismic lines 2. Conversion of microfossil relative abundance to numerical abundance Well folder: Microfossil data sheets for each of 49 wells 3. Table of seismic shot hole paleontology
Reports
Well folder: Interpretive report for each of 49 wells Plates
1. Correlation section B-1 of selected wells 2. Correlation section B-2 of selected wells 3. Correlation section B-3 of selected wells
Micropaleontology of Selected Wells and Seismic Shot Holes, Northern Alaska By Michael B. Mickey, Hideyo Haga, and Kenneth J. Bird Introduction and Summary
This report provides micropaleontologic data (foraminifera, pollen, spores, and microplankton) and interpretations of the rocks penetrated by 49 wells and 3,134 seismic shot holes distributed among 73 seismic lines (figs. 1, 2; table 1). All shot holes and 30 wells are located within the National Petroleum Reserve in Alaska (NPRA); the remaining 19 wells are located adjacent to the NPRA. The biostratigraphic zonation scheme, stratigraphy, and geologic ages followed in this study are summarized in figure 3. This update brings paleontologic analyses performed at various times over several decades to a current, unified set of interpretations that benefit from the evolution of northern Alaska biostratigraphic understanding developed during the past 33-years by Mickey and Haga.
For each well, paleontologic information includes microfossil distribution charts, data spreadsheets, diversity graphs, and interpretive reports describing age and environments of deposition. Three biostratigraphic well-correlation sections that relate Chukchi Sea wells to onshore northwestern NPRA wells are also included. For all analyzed seismic shot hole samples, foraminiferal age and environmental interpretations are provided; palynological interpretations are provided only for those shot hole samples collected and analyzed after 1976, a little less than half of the total number of samples. Background
All wells in this report were analyzed and reported on in earlier times. Those wells in the NPRA, with the exception of the Brontosaurus well, were studied as part of the 1974-1981 government program (Gryc, 1988). Summaries of those interpretations are provided in tabular form by Witmer, Haga, and Mickey (1981) and Witmer, Mickey, and Haga (1981) and in graphical form by Magoon and others (1988). Wells outside of the NPRA were studied on an individual and sometimes proprietary basis; only some of the reports are available in the public well files available from the Alaska Oil and Gas Conservation Commission, Anchorage, or from the Department of the Interior Minerals Management Service, Anchorage.
Paleontologic reports of seismic shot hole samples collected during the 1974 to 1981 NPRA program were made publicly available in 1981 (Gibson and Bowsher, 1981). Analyses of shot hole samples from earlier surveys (1947–1949) have not previously been publicly available. Those samples were processed only for foraminifera and the slides are presently archived at the Alaska Geologic Materials Center in Eagle River.
ALASKA
TeshekpukLake
Plate 3
Plate 2
Plate 1
160°W 155°W 150°W
68°N
69°N
70°N
71°N
Nuiqsut
Umiat
Barrow
Wainwright
Atqasuk
Lisburne
Cabot
Diamond
Akulik
TungakCreek
Tunalik
Koluktak
Seabee
Burger
Klondike
Crackerjack
Popcorn
Antares 1 Orion
Mars
NechelikSouth Harrison Bay
North Kalikpik
East Teshekpuk
Ikpikpuk
South MeadeKugrua
Peard
North Inigok
Inigok
Bergschrund 1
Kookpuk
Fiord 1
ItkillikRiver
West Fish Creek
Atigaru Point
Drew Point
East Simpson 1East Simpson 2
South Simpson
Kuyanak
West DeaseTulageak
Iko Bay
Cape Halkett
W.T. Foran
Fireweed
J.W. DaltonTexaco Colville Delta 1/1A
Walakpa 1
South Barrow 1
Walakpa 2
Brontosaurus
Awuna
NPRA boundary
Correlation sections
BLM lease sale planning areasUpdated wells
50 km
50 mi
Figure 1. Location of wells with updated paleontology and well-correlation sections.
Albers projection
10 0 10 20 30 40 50 KILOMETERS
10 0 10 20 30 40 MILES
Seismic lineShot hole location68°30’
69°00’
69°30’
70°00’
70°30’
71°00’
162°
160°158° 156°
154° 152°
NPRA boundary
1A4843A
4-48-43
3-48-43
3-48-43
5-48-43
2-48-43
2-48-43
2A-4
8-43
6-48-43
14-48-47
20-48-46
16-48-46 6-48-46
12-48-46
1-48-43
10-48-468-48-46
4-48-46
18-48-46
21-4
8-47
22-48-46
24-48
-47
26-4
8-47
19-48-47
23-48-47
27-4
8-47
28-48-4730-48-47
2B-48-43
29-48-4714A-48-47
Figure 2. Map showing location of seismic lines and shot holes with micropaleontology.
51-7
5
51-7
5
1-49-44
29-7
7
37-77
37X-
75
37X-
75
37X-
78
45X-
78
45-7
7
46-7
7
51X-
78
35-4
9-47
35-4
9-47
34-49-47
32-49-47
33-49-47
2-47-46
1-47-43
2-47-43
2-47-43
3-47-433-47-43
3-47-434-47-46
5-47-46
6-47-46
7-47
-43
8-47-43
9-47-46
10-47-4611-47-46
12-47-46
13-47-46
14-47-46
15-47-46
16-47-43
18-47-43
19-4
7-43
20-47-46
Table 1. Summary listing of wells and seismic lines with shot hole paleontology considered in this report. See figures 1 and 2 for locations.
WELLS DISTRIBUTION CHARTS (.PDF)
DATA SHEETS (.XLS)
DIVERSITY GRAPHS
(.PDF)
REPORT (.PDF)
SEISMIC LINES
1 Akulik X X X X 1-47 26-48 2 Antares 1 (OCS 280-1) X X X X 2-47 27-48 3 Atigaru Point X X X X 3-47 28-48 4 Awuna X X X X 4-47 29-48 5 Bergschrund 1 X X X X 5-47 30-48 6 Brontosaurus X X X X 6-47 1-49 7 Burger (OCS 1413) X X X X 7-47 1X-1-49 8 Cabot (OCS 0742) X X X X 8-47 2X-1-49 9 Cape Halkett X X X X 9-47 3X-1-49
10 Colville Delta 1/1A X X X X 10-47 5X-1-49 11 Crackerjack (OCS 1320) X X X X 11-47 5W-R-1-49 12 Diamond (OCS 0996) X X X X 12-47 32-49 13 Drew Point X X X X 13-47 33-49 14 East Simpson 1 X X X X 14-47 34-39 15 East Simpson 2 X X X X 15-47 35-49 16 East Teshekpuk X X X X 16-47 29X-77 17 Fiord 1 X X X X 18-47 37-77 18 Fireweed (OCS 0267) X X X X 19-47 37X-75 19 Iko Bay X X X X 20-47 37X-78 20 Ikpikpuk X X X X R? 45-77 21 Inigok X X X X 1-A-48 45X-78 22 Itkillik River Unit X X X X 2A-B-48 46-77 23 J.W. Dalton X X X X 2A-C-48 51-75 24 Klondike (OCS 1482) X X X X 2A-D-48 51X-78 25 Koluktak X X X X 2A-2-48 26 Kookpuk X X X X 2B-48 27 Kugrua X X X X R-1-17-48 28 Kuyanak X X X X 1-48 29 Lisburne X X X X 2-48 30 Mars (OCS 0302) X X X X 3-48 31 Nechelik X X X X 4-48 32 North Inigok X X X X 5-48 33 North Kalikpik X X X X 6-48 34 Orion (OCS 0804) X X X X 8-48 35 Peard X X X X 10-48 36 Popcorn (OCS 1275) X X X X 11-48 37 Seabee X X X X 12-48 38 South Barrow 1 X X X X 13-48 39 South Harrison Bay X X X X 14-48 40 South Meade X X X X 14A-48 41 South Simpson X X X X 16-48 42 Tulageak X X X X 17-48 43 Tunalik X X X X 18-48 44 Tungak Creek X X X X 19-48 45 Walakpa 1 X X X X 20-48 46 Walakpa 2 X X X X 21-48 47 West Dease X X X X 22-48 48 West Fish Creek X X X X 23-48 49 W.T. Foran X X X X 24-48
MICROPALEOCONSULTANTS
BIOSTRATIGRAPHY CHARTALASKAN - CANADIAN ARCTIC
Prepared By:MICHAEL B. MICKEY - FORAMINIFERA
HIDEYO HAGA - PALYNOMORPHSJanuary, 2006
329 Chapalita DriveEncinitas, CA 92024(760) 942-6082email: [email protected]
TIM
E (
Millio
n Y
ea
rs)
STA
GE
ER
A
EP
OC
H
PE
RIO
D
STANDARDCHRONOSTRATIGRAPHY
FO
RA
MZ
ON
E
DIN
OC
YS
TZ
ON
E
SP
OR
E -
PO
LL
EN
ZO
NE
GE
NE
RA
LIZ
ED
SE
QU
EN
CE
19
98
D
ETA
ILE
D N
PR
AT
RIA
S. -
NE
OC
.B
IOS
TR
AT.
UN
IT
BIOSTRATIGRAPHY
NORTH SLOPE, ALASKAGENERALIZED GROUPS,
FORMATIONS & MEMBERS
NORTHWESTRICHARDSONMOUNTAINS
CANADIANBEAUFORT
SEA
STRATIGRAPHY
STA
GE
CHRONO-STRAT.
ME
SO
ZO
IC
CR
ETA
CE
OU
SJ
UR
AS
SIC
TR
IAS
SIC
UP
PE
RU
PP
ER
UP
PE
RL
OW
ER
LO
WE
RL
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MID
DL
EM
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(BU
NT
SA
ND
ST
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US
CH
EL
KA
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)(K
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PE
R)
(IL
IAS
)(M
AL
M)
(DO
GG
ER
)(N
EO
CO
MIA
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(SE
NO
NIA
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65.5
UPPER
MIDDLELOWER
PIACENZIAN
ZANCLEAN
MESSINIAN
TORTONIAN
SERRAVALLIAN
LANGHIAN
BURDIGALIAN
AQUITANIAN
CHATTIAN
RUPELIAN
PRIABONIAN
BARTONIAN
LUTETIAN
YPRESIAN
THANETIAN
DANIAN
SELANDIAN
GELASIAN
23.03
20.43
3.6
5.33
7.25
11.61
13.65
15.97
28.4
33.9
37.2
40.4
48.6
55.8
58.7
61.7
2.591.806
0.781
0.126
PLIENSBACHIAN
KIMMERIDGIAN
CENOMANIAN
TURONIAN
CONIACIAN
SANTONIAN
CAMPANIAN
DIENERIAN
SMITHIAN
LADINIAN
RHAETIAN
HETTANGIAN
SINEMURIAN
TOARCIAN
AALENIAN
BAJOCIAN
BATHONIAN
CALLOVIAN
OXFORDIAN
112
70.6
83.5
85.8
89.3
93.5
99.6
125
130
136.4
140.2
145.5
150.8
155
161.2
164.7
167.7
171.6
175.6
183
189.6
196.5
199.6
203.6
216.5
228
237
245
IND
UA
NO
LE
NE
KIA
N
GRIESBACHIAN
SPATHIAN
ANISIAN
CARNIAN
NORIAN
MAESTRICHTIAN
TITHONIAN
BERRIASIAN
VALANGINIAN
HAUTERIVIAN
BARREMIAN
APTIAN
ALBIAN
253.8
260.4
265.8
268
270.6
275.6
284.4
294.6
299
303.9
306.5
311.7
318.1
326.4
345.3
359.2
370
CHANGHSINGIAN
WUCHIAPINGIAN
CAPITANIAN
WORDIAN
ROADIAN
KUNGURIAN
ARTINSKIAN
SAKMARIAN
ASSELIAN
GZHELIAN
KAZIMOVIAN
MOSCOVIAN
BASHKIRIAN
SERPUKHOVIAN
VISEAN
TOURNAISIAN
DE
VO
NIA
NU
ND
IFF
ER
EN
TIA
TE
D
PLIENSBACHIAN
KIMMERIDGIAN
CENOMANIAN
TURONIAN
CONIACIAN
SANTONIAN
CAMPANIAN
DIENERIAN
SMITHIAN
LADINIAN
RHAETIAN
HETTANGIAN
SINEMURIAN
TOARCIAN
AALENIAN
BAJOCIAN
BATHONIAN
CALLOVIAN
OXFORDIAN
112
70.6
83.5
85.8
89.3
93.5
99.6
125
130
136.4
140.2
145.5
150.8
155
161.2
164.7
167.7
171.6
175.6
183
189.6
196.5
199.6
203.6
216.5
228
237
245
IND
UA
NO
LE
NE
KIA
N
GRIESBACHIAN
SPATHIAN
ANISIAN
CARNIAN
NORIAN
MAESTRICHTIAN
TITHONIAN
BERRIASIAN
VALANGINIAN
HAUTERIVIAN
BARREMIAN
APTIAN
ALBIAN
251
249.7
253.8
260.4
265.8
268
270.6
275.6
284.4
294.6
299
303.9
306.5
311.7
318.1
326.4
345.3
359.2
370
CHANGHSINGIAN
WUCHIAPINGIAN
LO
PIN
GIA
N
CAPITANIAN
GU
AD
AL
UP
IAN
WORDIAN
ROADIAN
KUNGURIAN
ARTINSKIAN
SAKMARIAN
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UR
AL
IAN
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PE
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MOSCOVIAN
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IAN
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F-6
F-7
F-8
F-9
F-10
F-11
F-12
F-13a
F-1
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F-1
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-15
F-1
6a
F-1
6b
F-1
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-18
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F-18c
F-19a
F-1
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F-1
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L
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F - 2A (1)
F - 2A (2)
F - 2A / 2B
F - 2B (1)
F - 2B (2)
F - 2B (3)
F - 3A (1)
F - 3A (2)
F - 3A (3)
F - 3A (4)
F - 3B (1)
F - 3B (2)
F - 3B (3)
F - 3B (4)
F - 4 (1)
F - 4 (2)
U
U
L
L
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P-M13 P-T11
P-M14
P-M15
P-M16
P-M17
P-M19
P-M
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P-M
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a
P-M20
P-M21
P-M22
P-M
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P-M23
P-M24
P-M25
P-M26
P-M27
P-T12
P-T16
P-T
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P - M 11a
N O
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P - M 11b
P - M 11c
P - M 12 P - T 10
P-T20
P-T21
a
b
P-T22
P-T18
P-T19
~~
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~~~~~~~~~
~~~~~~~~~
~~~~~~~~~
~~~~~~~~~
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~~~~~~~~~
~~~~~~~~~
~~~~
~~
~~
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MARTIN CREEK(BUFF DIVISION)
PA
RS
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LE
~ ? ~ ~ ? ~ ~ ? ~
~~~~~~~~~
~~~~~~~~~
CARBONATEUNIT
SHALE UNIT
SDST UNIT
IMPERIAL
~~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~
~~~~
~~~~
~~~~
~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~
~~~~
~~~
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LV
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SILTSTONEMBR.
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KAVIK FM.
LOWER KINGAK FM.
~~~
LOWER KINGAK FM.
UPPERKINGAK FM.
~~~~
~~~~
~~~~~~
~~~~~~
LisburneL.S., Sh
70
75
80
85
90
95
100
105
110
115
120
125
135
130
140
145
150
155
160
165
170
175
180
185
190
195
200
205
210
215
220
225
230
235
240
245
250
0
5
10
15
20
25
30
35
40
45
50
55
60
65
Drafted by: Ed Padilla1Modified from Molenaar, Bird & Kirk, 1987Absolute Ages from Gradstein, Ogg, Smith, et al. (2004)
251
Color Code according to the United States Geological Survey
CE
NO
ZO
ICT
ER
TIA
RY
PA
LE
OG
EN
EN
EO
GE
NE
23.03
20.43
3.6
5.33
7.25
11.61
13.65
15.97
28.4
33.9
37.2
40.4
48.6
55.8
58.7
61.7
2.59
0.781
0.126
1.806
65.5
UPPER
MIDDLE
LOWER
PIACENZIAN
ZANCLEAN
MESSINIAN
TORTONIAN
SERRAVALLIAN
LANGHIAN
BURDIGALIAN
AQUITANIAN
CHATTIAN
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5 Ma
~~~~~~~~~
~
~~
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~~~
~~
~~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~
~~~~
~~~
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~~
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~~
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~~~~~~~~~
~~~~~~~~~
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~~~
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~~~
~~~~
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~~~~ ~~ ~
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~
~~~
~~~~~~~~~
~~~~
~~~~
~
~~~
42-45 Ma
~~~~~~~~~
~~~~
~~~~
~~
~~~~~~~~~
~~~~~~~~~51-53 Ma
~~~~~~~~~
~~~~~~~~~60-62 Ma
~~~~~~~~~~~~~~~~~~
~~~~
~~~~~~~~~~~~~
~
~~
~~~~~~~~~~~~~~~~~~~~~~
GUBIK FM.
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“LO
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.
255
260
265
270
275
280
285
290
295
300
305
310
315
320
325
330
335
340
345
350
355
360
365
370
F-20b
F-21
MAMET’SZONES
M24
|
M22
M21
M20
M19
M18
M17
M16
M15
M14
M13
M12
M11
M10
M9
M8
M7
M6
M5
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UP
~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~
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UNNAMED SHALEEC
HO
OK
A F
M.
“JOE CREEKLIMESTONE”
~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~
“UP
PE
R L
IME
ST
ON
E U
NIT
”
“LO
WE
R L
IMY
UN
IT”
“DOLOMITE UNIT”
KA
YA
K F
M.
ITK
ILY
AR
IAK
FM
.
KEKIKTUK FM.
Basement, Argillite, Quartzite& Schist
No Pattern
Nonmarine Conglomerate or Sandstone
Marginal Marine Sandstone or Silstone
Sandstone
Shale or Mudstone
Slightly Organic Shale
Moderately Organic Shale
Highly Organic Shale
Shelly Calcarenite
Limestone
Dolomite
Conglomerate
Sandstone
Siltstone & Shale or Mudstone
STRATIGRAPHY LEGEND
Colors Patterns
Current Study
In the current study, no new well samples were processed or analyzed. Data from existing paper copy records were transcribed and age interpretations were reviewed and, in some cases, reinterpreted. Three types of displays were created from the transcribed data: distribution charts, data sheets, and diversity graphs. Distribution charts show relative microfossil abundances plotted against depth. Data sheets show relative abundances converted to numerical abundances according to the scheme in table 2 and plotted against depth. Diversity graphs show total microfossil abundance and number of species (diversity). A narrative report for each well provides interpreted ages and environments of deposition. Also, for the five wells located in the Chukchi Sea, biostratigraphic correlation charts (plates 1-3) were created that tie those wells to selected onshore wells in northwestern NPRA.
Data from existing paper copy records of seismic shot hole samples collected
from 1975 to 1978 were also transcribed. Foraminiferal slides from seismic shot hole samples collected from 1947 to 1949 were newly analyzed and interpreted at the Eagle River Geologic Materials Center, Alaska.
The data and results of this study are organized in the following way. For each of
the 49 wells, a separate folder is provided, within which relevant files of distribution charts, data sheets, diversity graphs, and reports are located. All seismic shot hole information is provided in a single Excel file (table 3) with multiple worksheets. Table 2. Explanation of conversion of microfossil relative abundances to numerical mid-point values necessary for creating diversity plots. Foraminifera
RELATIVE ABUNDANCE NUMERICAL ABUNDANCE Symbol Descriptor Range Mid-Point* Mid-Point Formula
X Very Rare 1 1 (1 + 1)/2 R Rare 2 – 4 3 (2 + 4)/2 F Frequent 5 – 25 15 (5 + 25)/2 C Common 26 – 100 63 (26 + 100)/2 A Abundant 101 – 1000 550 (101 +1000)/2 P Prolific 1001 - 5000 3000 (1001 + 5000)/2
Palynology (spore, pollen, microplankton)
RELATIVE ABUNDANCE NUMERICAL ABUNDANCE Symbol Descriptor Range Mid-Point* Mid-Point Formula
X Very Rare 1 1 (1 + 1)/2 R Rare 2 – 5 3 (2 + 5)/2 F Frequent 6 – 15 10 (6 + 15)/2 C Common 16 – 30 23 (16 + 30)/2 A Abundant 31 – 500 265 (31 +500)/2 P Prolific 501 - 5000 2750 (501 + 5000)/2
* Values rounded down to nearest integer.
Distribution Charts
Typically for each well there is one palynology distribution chart (P) and one to as many as four foraminiferal distribution charts (F), depending on number of samples analyzed. All are in Adobe Acrobat® pdf-format and are identified in the well folder by the label “C-(well name).pdf”. These charts show microfossil occurrence and relative abundance by well depth in feet. The foraminiferal charts also include observed occurrences of radiolaria (RADS.), miscellaneous other microfossils, shell fragments, and distinctive rock, mineral, and hydrocarbon occurrences. Also included on the plots are interpreted age, stage, zone and environment of deposition and faunal statistics.
Data Sheets
Data sheets show numerical (mid-point) abundance converted from relative
abundance according to the scheme shown in table 2. Data sheets are in Microsoft Excel® format and are identified in the well folder by the label “S-(well name).xls”. All of the microfossil and other components recorded on the distribution charts are incorporated here. For selected wells, a brief description of the lithology observed in the processed foraminiferal sample is included.
Diversity Graphs
Using the numerical values reported in the data sheets, graphs were created
showing diversity (number of species) and total abundance of foraminifera, spore-pollen, and microplankton, respectively, for each well. These plots, labeled High Resolution Biostratigraphy Plots, Foraminifera/Palynomorphs, are identified in the well folder by the label “DV-(well name).pdf”.
Reports
For each well, a narrative report in is included. This report typically provides a
brief description of the number of samples analyzed, the processing and reporting procedures, and the results of the analysis. Results are presented in both abbreviated form—just depth and age—and more detailed form consisting of microfossil zone, a listing of distinctive microfossils, the interpreted environment of deposition, and a brief discussion. These reports are identified in the well folder by the label “R-(well name).pdf”. Seismic Shot Hole Samples
Analyzed NPRA seismic shot hole samples (total 3,134) are from the exploration program of 1946-1953 conducted by the U.S. Navy and from the program of 1974-1981, initially conducted by the U.S. Navy and later, by the U.S. Department of the Interior. Shot hole samples, typically collected at depths of about 100 ft but some from as deep as 290 ft, provide information on near-surface geologic units where exposures are poor to
nonexistent. The older set of shot hole samples (1,710) consists only of foraminiferal slides on file at the Alaska Geologic Materials Center in Eagle River, Alaska. Those slides were analyzed by Mickey in 2001 and 2002 at Eagle River. No comparable palynologic slides for those samples exist. The newer set of shot hole samples (1,424) includes both foraminiferal and palynologic analyses performed on contract to the U.S. Geological Survey during the exploration program of 1974-1981 (Gibson and Bowsher, 1981). Fossil checklists of these samples were reviewed and reinterpreted for this study. Shot hole details (seismic line and shot hole number, sample depth if available, and latitude-longitude location) and paleontologic interpretations are presented in table 52; seismic lines are located in figure 2. Location information has been lost for a number of the older U.S. Navy shot holes and has been left blank on table 3. Acknowledgements This compilation was facilitated by behind-the-scene data retrieval, plotting, drafting, and general organizational efforts of Megan Simpson, Zenon Valin, and Nick Zihlman of the U.S. Geological Survey, and Edward Padilla of Miropaleo Consultants. This report has benefited from the reviews of Mary McGann and Margaret Keller. References Cited Gibson, H.A., and Bowsher, A.L., 1981, Availability of foraminifera and palynomorph
reports from shot hole samples of National Petroleum Reserve in Alaska: U. S. Geological Survey Open-File Report 81-1340, 3 p.
Gradstein, F.M., Ogg, J.G., and Smith, A.G., eds., 2004, A geologic time scale 2004,
Cambridge University Press, 589 p.
Gryc, G., ed., 1988, Geology and exploration of the National Petroleum Reserve in Alaska, 1974 to 1982, U.S. Geological Survey Professional Paper 1399, 940 p.
Magoon, L.B., Bird, K.J., Claypool, G.E., Weitzman, D.E., and Thompson, R.H., 1988,
Organic geochemistry, hydrocarbon occurrence, and stratigraphy of government-drilled wells, North Slope, Alaska, in Gryc, G., ed., Geology and exploration of the National Petroleum Reserve in Alaska, 1974 to 1982, U.S. Geological Survey Professional Paper 1399, p. 483–487.
Witmer, R.J., Haga, H., and Mickey, M.B., 1981, Biostratigraphic report of thirty-three
wells drilled from 1975 to 1981 in the National Petroleum Reserve in Alaska: U. S. Geological Survey Open-File Report 81-1166, 50 p.
Witmer, R.J., Mickey, M.B., and Haga, H., 1981, Biostratigraphic correlations of selected
test wells of National Petroleum Reserve in Alaska: U.S. Geological Survey Open-File Report 81-1165, 89 p.