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Carbon isotopic comparisons of oil products used in the developmental history of Alaska
Chemical Geology 152 Ž1998. 73–84
Carbon isotopic comparisons of oil products used in the developmental history of Alaska Keith A. Kvenvolden a,) , Paul R. Carlson a , Augusta Warden b, Charles N. Threlkeld b a b
U.S. Geological SurÕey, 345 Middlefield Road, MS 999, Menlo Park, CA 94025, USA U.S. Geological SurÕey, Federal Center, Box 25046, MS 977, DenÕer, CO 80225, USA
Abstract Studies of the fate of oil released into Prince William Sound, AK, as a result of the 1989 Exxon Valdez oil spill, have led to an unexpected discovery. In addition to oil-like residues attributed to the spill, the ubiquitous presence of flattened tar balls, the carbon isotopic compositions of which fall within a surprisingly narrow range w d 13 C PDB s y23.7 " 0.3‰ Ž n s 65.x, were observed on the shorelines of the northern and western parts of the sound. These compositions are similar to those of some oil products wy23.7 " 0.7‰ Ž n s 35.x that were shipped from California and used in Alaska for fuel, lubrication, construction, and paving before ; 1970. These products include fuel oil, asphalt, and lubricants wy23.8 " 0.5‰ Ž n s 11.x, caulking, sealants, and roofing tar wy23.7 " 0.7‰ Ž n s 16.x, and road pavements and airport runways wy23.5 " 0.9‰ Ž n s 8.x. Fuel oil and asphalt wy23.5 " 0.1‰ Ž n s 3.x, stored at the old Valdez town site and spilled during the 1964 Alaskan earthquake, appear to be the source of most of the beached tar balls. Oil products with lighter carbon isotopic compositions, between y25 and y30‰ Ž n s 18., appear to have been used more recently in Alaska, that is, after ; 1970. The source of some of the products used for modern pavement and runways wy29.3 " 0.2‰ Ž n s 6.x is likely Alaskan North Slope crude oil, an example of which was spilled in the 1989 oil spill wy29.2‰ Ž n s 1.x. q 1998 Elsevier Science B.V. All rights reserved. Keywords: Alaska; Exxon Valdez; Alaskan North Slope crude oil; Fuel oil; Carbon isotopic comparisons
1. Introduction Following the 1989 Exxon Valdez oil spill in Prince William Sound, AK, a multi-year program was begun to assess the geological fate and impact of the spilled Alaskan North Slope crude oil. Starting in 1990 and continuing in 1992–1996, oil-like residues from the shorelines throughout the sound were collected and analyzed. In a preliminary geo)
Corresponding author
chemical study of eight of the first samples collected, it was discovered that six of the samples were weathered residues of North Slope crude oil, most likely spilled from the Exxon Valdez supertanker. Two flattened tar ball samples, however, had molecular and carbon isotopic characteristics of a crude oil source in the Miocene Monterey Formation of California ŽKvenvolden et al., 1993a.. These two samples came from localities about 100 km apart on Storey Island and Elrington Island ŽFig. 1a.; this observation led to the conclusion that oil residues
0009-2541r98r$ - see front matter q 1998 Elsevier Science B.V. All rights reserved. PII: S 0 0 0 9 - 2 5 4 1 Ž 9 8 . 0 0 0 9 7 - 7
74 K.A. KÕenÕolden et al.r Chemical Geology 152 (1998) 73–84
Fig. 1. Prince William Sound area and southern Alaska, showing locations of oil residues and oil products. Ža. Exxon Valdez oil and residues Žtriangles., Monterey-Californiasourced residues Žsquares. and exceptions Žcircles. from Appendix A. Žb. Oil products used in the area of Prince William Sound Ždiamonds.. Sample numbers Žlast digit of year-number.. Data from Table 1, Table 2 and Table 3. Abbreviations are: E, Ellamar; GM, Granite Mine; MB, McClure Bay; N, Nuchek; PB, Pigot Bay; PC, Passage Canal; PNJ, Port Nellie Juan; PW, Port Wells; SC, Shotgun Cove. Žc. Oil products used in southern Alaska Ždiamonds. and natural seeps and oil in the Gulf of Alaska Žpentagons.; Exxon Valdez residues Žtriangles.. Sample numbers Žlast digit of year-number.. Data from Table 1, Table 3 and Table 4. Abbreviations are: Am, Amchitka; At, Attu; B, Bethel; CB, Cold Bay; Ch, Chilkat; Co, Cordova; DH, Dutch Harbor; G, Gustavus; Ka, Katalla; Ko, Kodiak Is.; KS, King Salmon; P, Palmer; S, Seward; Sh, Shuyak Is.; V, Valdez; W, Whittier.
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Fig. 1 Žcontinued..
with similar geochemical characteristics could be present on many other shorelines of the Sound. This conclusion was verified when, on the basis of carbon isotopic and biomarker characteristics of 61 samples from widely dispersed localities, it was shown ŽKvenvolden et al., 1993b, 1995. that probable Monterey-California-sourced, oil-like residues are ubiquitous on the shorelines of the northern and western parts of Prince William Sound ŽFig. 1a.. The inventory of oil-like residues from the shorelines of Prince William Sound Žanalyzed for carbon isotopic compositions—Appendix A. now contains 31 samples of Alaskan North Slope crude oil Žlikely Exxon Valdez residues., 65 samples of probable Monterey-California-sourced residues, and only two exceptions from unknown sources ŽFig. 2A; sample locations in Fig. 1a.. Analyses of carbon isotopic compositions Žreported in ‰ values relative to the Peedee belemnite ŽPDB. standard. indicate that the average carbon isotopic composition of the suite of 31 residues Žy29.3 " 0.1‰. is not significantly different from the isotopic composition of the oil spilled
from the Exxon Valdez supertanker Žy29.2‰; Table 1, sample 89-0.. Thus, the 31 residues are referred to as Exxon Valdez residues, although it is possible, but not likely, that some of these residues could be from other minor spills of North Slope crude oil. Biomarker data on 25 of these samples support the connection with the Exxon Valdez spill ŽHostettler and Kvenvolden, 1994; Kvenvolden et al., 1995.. The supertanker carried a mixed load of Alaskan North Slope crude oil; therefore, the ultimate source of Exxon Valdez residues is North Slope oil. The 65 probable Monterey-California-sourced residues have uniquely heavy carbon isotopic compositions of y23.7 " 0.3‰. The carbon isotopic compositions of all of these samples and biomarker analyses ŽKvenvolden et al., 1995. of 38 of these same samples clearly show a correlation with geochemical properties of crude oils from Miocene Monterey Formation source rocks of California ŽKvenvolden et al., 1993a,b, 1995.. Thus, although the ultimate source of the 65 residues is in California, the intermediate source or sources is still uncer-
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Fig. 2. Histograms of carbon isotopic compositions Ž d 13 C‰. of oil residues and oil products in Alaska. ŽA. Oil-like residues on shorelines of Prince William Sound. ŽB. Fuel oils, asphalt, and lubricants. ŽC. Caulking, sealants, and roofing tar. ŽD. Road pavements and airport runways. ŽE. Natural seeps and oil, Gulf of Alaska.
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Table 1 Carbon isotopic compositions Ž d 13 C‰. of fuel oils, asphalt, and lubricants used in Alaska Sample no.
Location
Fuel oils, asphalt, and lubricants 92-6 Old Valdez 92-30 Latouche I. 92-31 Latouche I. 94-3A Evans I. 94-4 Evans I. 94-19 Bethel 95-11B Old Valdez 95-11C Old Valdez 95-19 McClure Bay 95-21 McClure Bay 95-22 McClure Bay 89-0 Bligh Reef 95-23A P. Nellie Juan 95-37 Granite Mine
Latitude ŽN. X
61807.0 X 60803.2 X 60803.2 X 60804.0 X 60803.5 X 60847.5 X 61806.8 X 61806.8 X 60832.9 X 60832.9 X 60832.9 X 60851.3 X 60835.5 X 60858.0
Longitude ŽW. X
146816.5 X 147854.1 X 147854.1 X 148800.5 X 148803.2 X 161845.0 X 146816.0 X 146816.0 X 148809.9 X 148809.9 X 148809.9 X 146852.5 X 148806.7 X 148812.3
tain. In order to explore possible intermediate tain. In order to explore possible intermediate sources, we undertook a survey of various oil products used in Alaska with emphasis on older products which were used before Alaska obtained its own internal crude oil supply after ; 1970. This paper examines the carbon isotopic compositions of Ž1. fuel oils, asphalt, and lubricants, Ž2. caulking, sealants, and roofing, and Ž3. road pavements and airport runways. In addition, we report on the carbon isotopic compositions of natural seeps and oil in the Gulf of Alaska. 2. Methods Oil-like residues were collected from beaches, mainly at the high tide line, by removing the flattened tar balls from rock surfaces with a pre-cleaned knife, wrapping the sample in pre-cleaned aluminum foil, and storing the wrapped sample in a labeled sack. Oil products were removed from various structures and surfaces using a pre-cleaned knife and stored in the same manner as the oil-like residues. In the laboratory, the oil-like residues and oil products were dissolved in dichloromethane, and the resulting solutions were filtered through glass wool and concentrated to remove the solvent; a portion Ž40–90 mg. of each extract was then recovered for determination of carbon-isotopic composition. For this determination, at least 4 mg of each extract was placed in
d 13 C Ž‰.
Description
y23.6 y24.8 y24.3 y24.3 y23.4 y23.3 y23.5 y23.4 y23.7 y23.8 y23.7 y29.2 y27.7 y25.3
Tar mat, site of fuel and asphalt storage plants Tar in mine dump Oil at toe of mine dump Sticky oily mat in dump, Chenega Bay Tar from storage tank, Port Ashton Asphalt from leaking storage drum Tar on cobble, site of fuel and asphalt storage Tar mat, site of fuel and asphalt storage plants Oil on abandoned equipment on beach Oil in valve of cannery fuel oil storage tank Tar on rock below cannery oil storage tank North Slope crude oil in Exxon Valdez Motor oil in cabin, south of entrance Grease in storage drum on beach
an evacuated quartz tube with cupric oxide, as a source of oxygen, and a strip of silver metal, as a catalyst, and combusted to 8408C. The resulting CO 2 was purified under vacuum by differential temperature transfer and measured by isotope-ratio mass spectrometry. The results are reported in delta Ž d . notation in parts per thousand Ž‰. relative to the PeeDee Belemnite ŽPDB. standard; accuracy of duplicate analyses is 0.1‰. 3. Results and discussion In the historical development of the economy of Alaska, California has served as a principal source of oil products since the early part of the 20th century. Oil products were shipped commonly by barge from ports such as El Segundo and Richmond in California ŽWhite, 1962; Standard Oil of California, 1979. to ports such as Whittier on the west edge and Valdez at the north end of Prince William Sound, where fuel oil and asphalt have been stored and distributed. Although Alaskan crude oil was produced at Katalla on the Gulf of Alaska from 1904 to 1933, it was not until North Slope crude oil, discovered at Prudhoe Bay in 1968, reached the Valdez terminal in 1977 that Alaska had a sufficient supply of oil to satisfy even more than its own economic needs. Since then, California oil products have become much less significant. In the following discus-
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sions the historical aspects related to our various samples are taken mainly from Lethcoe and Lethcoe Ž1994.. 3.1. Fuel oils, asphalt, and lubricants Carbon isotopic compositions were measured on 14 oil products representing currently or previously stored fuel oils, asphalt, and lubricants ŽTable 1; Fig. 1b, Fig. 2B.. Eleven of these samples have an average carbon isotopic composition of y23.8 " 0.5‰, similar to the average composition of MontereyCalifornia-sourced residues Žy23.7 " 0.3‰.. At sites of fuel oil and asphalt storage facilities in the old town of Valdez, three samples of tar Žy23.5 " 0.1‰. were collected which are believed to represent the oil products stored at the time of the 1964 Great Alaska Earthquake. This earthquake destroyed the old town of Valdez and caused fuel and asphalt to spill into the fjord of Port Valdez at the north end of Prince William Sound ŽWilson and Tørum, 1972.. Fuel oil had been stored at the old town of Valdez since at least the 1940s, and an asphalt plant was built there in 1952. These facilities were removed sometime after 1964. McClure Cannery, located on McClure Bay, Port Nellie Juan, ŽFig. 1b. is now abandoned. This cannery was first opened in 1917 and ceased major operations in 1959. At the abandoned ruins we found three samples of fuel oil Žy23.7 " 0.1‰. associated with a small supply tank at the old power plant. Small quantities of oil are still leaking into the Sound. On Evans Island ŽFig. 1. fuel oil Žy23.4‰. was sampled from abandoned tanks at Port Ashton, and sticky oil Žy24.3‰. was collected from a dump at Chenega Bay. Port Ashton was a major center for herring processing from 1914 into the 1930s; the dump at Chenega Bay was the site at which a storage tank once stood as part of an old saltery or cannery. Tar Žy24.3‰. and oil Žy24.8‰. associated with a mine dump were sampled on Latouche Island ŽFig. 1b. where these oil products have apparently been used in ore separation processes. Mining of copper began here in 1897 and continued on and off until 1938. Some new mining activity is again taking place there. The last sample of this isotopically heavy group of 14 samples was obtained from a leaking storage drum of asphalt Žy23.3‰. that was
washed into the Kuskokwim River near Bethel, Alaska ŽFig. 1c.. As many as 3000 to 4000 drums of asphalt were buried at the site of a military airport constructed between 1941 and 1943. The asphalt was originally intended for paving the runway. These drums and their contents now represent a serious environmental hazard. Three samples were found with carbon isotopic compositions lighter than y25‰. These include a sample of crude oil from the supertanker Exxon Valdez Žy29.2‰., the source of Exxon Valdez residues on shorelines of Prince William Sound, a sample of grease Žy25.3‰. in a storage drum washed above the beach near the Granite Mine site ŽFig. 1b. where a gold mine once existed, and a sample of Chevron SAE 30 motor oil Žy27.7‰. found in an abandoned cabin on the south side of the entrance to Port Nellie Juan ŽFig. 1b.. These samples represent post ; 1970 stored oil products used in Alaska. 3.2. Caulking, sealants, and roofing tar Table 2 lists 21 samples of oil products used in Alaska in various aspects of construction. Sixteen of these samples have an average carbon isotopic composition of y23.7 " 0.7‰, with samples falling in a range similar to the old fuel oils, asphalt, and lubricants and the Monterey-California-sourced residues Žcompare Fig. 2C with Figs. 2B and 2A.. A cannery, started in 1924 by the Pacific American Company near Cannery Creek in Unakwik Inlet ŽFig. 1b. and abandoned sometime after 1936, yielded two samples—caulking on a beam Žy23.0‰. and tar paper from a roof. The tar paper sample was extracted with dichloromethane, and the carbon isotopic composition of the recovered extract was measured Žy23.3‰.. Other tar paper samples were treated similarly. Tar was collected at two different sites on Latouche Island ŽFig. 1b.; one sample of tar Žy23.6‰. was found on a telephone pole near a mine dump on the northwest side of the island, and caulking Žy23.8‰. was obtained from a log on a storm berm in Sleepy Bay. Tar on pilings of an abandoned wharf Žy23.6‰. and tar sealant on a metal roof of a ruined building Žy23.8‰. were recovered at the cannery on McClure Bay that was discussed previously. Ellamar ŽFig. 1b. was the site
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Table 2 Carbon isotopic compositions Ž d 13 C‰. of caulking, sealants, and roofing tar used in construction in Prince William Sound, AK Sample no.
Location
Caulking, sealants, and roofing 92-3 Whittier 92-32 Latouche I. 94-2E Latouche I. 94-16 Unakwik Inl. 94-17 Unakwik Inl. 95-4 Chilkat 95-5 Chilkat 95-7 Nuchek 95-8B Ellamar 95-9 Ellamar 95-17 McClure Bay 95-20 McClure Bay 95-24 Shotgun Cove 95-25 Shotgun Cove 95-31 Perry I. 95-32 Pigot Bay 95-10 Old Valdez 95-30 Perry I. 95-34 Pigot Bay 95-38 Granite Mine 95-39 Esther I.
Latitude ŽN. X
60846.5 X 60803.2 X 60804.0 X 61800.5 X 61800.5 X 60811.3 X 60811.3 X 60820.0 X 60853.7 X 60853.7 X 60832.9 X 60832.9 X 60847.8 X 60847.8 X 60841.1 X 60850.5 X 61806.9 X 60841.1 X 60850.4 X 60858.3 X 60848.0
Longitude ŽW. X
148840.3 X 147854.1 X 147850.6 X 147831.5 X 147831.5 X 144813.0 X 144813.0 X 146839.5 X 146842.1 X 146842.1 X 148809.9 X 148809.9 X 148831.8 X 148831.8 X 147855.2 X 148819.4 X 146816.2 X 147855.2 X 148823.2 X 148811.9 X 148805.0
of a copper mine from 1900 to 1929 and then a cannery that closed about 1955. A sample of tar from the piling of an abandoned wharf Žy23.4‰. and a sample of tar binding a cable on the boat pier Žy23.3‰. were collected here. At the former site of Chilkat on the Bering River ŽFig. 1c., samples were obtained of tar on chimney flashing Žy22.9‰. and of tar paper from a collapsed cabin Žy22.9‰.. Other isotopically heavy Ž) y25‰. construction tars were found on a timber on the beach at Nuchek Žy24.0‰. on Hinchinbrook Island and on a plank above the beach at Pigot Bay Žy23.7‰. on the west side of the entrance to Port Wells ŽFig. 1b.. On Perry Island ŽFig. 1b., an oyster farm has taken the place of the South Perry Island Fox Farm which closed in 1945. Tar on a boat shed support here has a carbon isotopic composition of y24.8‰. The St. Elias Ocean Products floating cannery, operating since 1964, was beached in a storm and abandoned in 1979 in Shotgun Cove on the south side of Passage Canal ŽFig. 1b.. Two tar samples were collected from this wreck–tar on metal roofing Žy24.8‰. and tar impregnated roofing fabric Žy22.9‰.. In the
d 13 C Ž‰.
Description
y24.9 y23.6 y23.8 y23.3 y23.0 y22.9 y22.9 y24.0 y23.4 y23.3 y23.6 y23.8 y24.8 y22.9 y24.8 y23.7 y29.3 y28.7 y25.4 y26.0 y27.3
Tar roofing from Buckner Building Tar on telephone pole at mine dump Tar on log, Sleepy Bay Tar paper on roof at abandoned cannery Tar on beam at abandoned cannery Tar on chimney flashing of ruined building Tar paper from ruined building Tar on timber on beach Tar on piling of abandoned wharf Tar on cable binding on pier Tar on piling of abandoned wharf Tar on metal roofing of ruined building Tar on metal roofing of abandoned barge Tar coating of roof fabric of abandoned barge Tar on support for boat shed Tar on plank above the beach Tar in hold of wreck of Emerald Pacific Tar on chimney flashing at oyster farm Tar on roof of Forest Service cabin Tar on metal roofing sheets in shed Tar roofing shingle from fish hatchery
town of Whittier ŽFig. 1b and c., the seven story Buckner Building was completed in 1952 but abandoned in 1964 as a result of the earthquake. A sample of roofing tar Žy24.9‰. from this building was analyzed. Most of the samples just discussed have not yet been fractionated and examined for biomarkers. Some samples, especially those from pilings could be creosote, a coal tar product rather than an oil tar material. If any of these samples are actually creosote, then arguments for a California source for these samples are not necessarily valid because coal tars in general have heavy carbon isotopic compositions. Four construction tar samples had carbon isotopic compositions between y25 and y30‰. These samples are tar on chimney flashing Žy28.7‰. near the barn of the oyster farm on Perry Island, sealant on the roof Žy25.4‰. of a modern Forest Service cabin on the south shore of Pigot Bay, tar on metal roofing sheets Žy26.0‰. stored in a small shed above the beach near the site of Granite Mine, and tar from a roof shingle Žy27.3‰. from the Wally Noerenberg Hatchery, built in 1984 on Esther Island ŽFig. 1b..
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The ship Emerald Pacific was beached and abandoned for salvage at the old Valdez town site in 1992. Tar from inside the exposed hold Žy29.3‰. was sampled in May 1995. Surprisingly this tar has the same carbon isotopic composition as Alaskan North Slope crude oil and Exxon Valdez residues ŽFig. 2C and Fig. 2A.. J.T. Williams Žpersonnel communication, 1995., the salvage owner, indicated that the Emerald Pacific had been involved in the cleanup of the Exxon Valdez oil spill. The ship was subsequently damaged, and the tar that was sampled had likely been used to try to plug the leaking hull. 3.3. Road paÕements and airport runways Eighteen examples of pavements and runways were examined for their carbon isotopic compositions ŽTable 3.. Eight of these samples have an average carbon isotopic composition of y23.5 " 0.9‰, values similar to those of old oil products and Monterey-California-sourced residues Žranging from y22.3 to y24.9‰. Žsee Fig. 2.. Street pavements in Whittier near the 14-story Hodge Building Žnow called Begich Towers., which was built in 1956, and near the Buckner Building Žoccupied from 1952 to
1964. were sampled, giving carbon isotopic compositions of y24.8 and y24.3‰, respectively. Tar-cemented gravel near one end of the gravel runway in Whittier measured y24.2‰. Samples of old runways Žsee Fig. 1c for locations. at Gustavus Žy23.5‰., Amchitka Žy23.4‰., Attu Žy22.8‰., Cold Bay Žy22.7‰., and Cordova Žy22.3‰. all have carbon isotopic compositions heavier than y25‰. In contrast, new pavements near Whittier and Valdez have isotopically light compositions of y29.4 and 27.7‰, respectively. Samples of new airport runways ranged from y27.2 to y29.6‰—Valdez Žy27.2‰., Seward Žy28.1‰., Kodiak Žy27.1‰., King Salmon Žy29.6‰., Dutch Harbor Žy29.1‰., and Palmer Žy29.3‰.. Tar, probably used for patching, spilled adjacent to the active runway at Cordova has a composition of y29.1‰, and tar chunks in riprap near the end of the gravel runway in Whittier have a composition of y29.4‰. Within this group, six of the pavement samples, with carbon isotopic compositions ranging from y29.1 to y29.6‰, likely were made of tar produced from North Slope crude oil. This conclusion is based on the similarity of carbon isotopic compositions of these samples, ap-
Table 3 Carbon isotopic compositions Ž d 13 C‰. of road pavements and airport runways in Alaska Sample no.
Location
Latitude ŽN.
Road pavements and airport runways X 92-1 Whittier 60846.3 X 92-4 Whittier 60846.5 X 92-42 Gustavus 58829.0 X 92-45C Amchitka 51823.4 X 92-46C Attu 52849.4 X 92-49B Cold Bay 55812.9 X 95-6B Cordova 60829.6 X 95-28 Whittier 61846.5 X 92-7 Valdez 61807.9 X 92-8 Valdez 61808.6 X 92-34 Seward 60807.7 X 92-43B Kodiak 57845.0 X 92-44C King Salmon 58841.4 X 92-47 Dutch Harbor 53853.8 X 95-6A Cordova 60829.6 X 95-12 Palmer 61835.7 X 95-26 Whittier 60846.5 X 95-27 Whittier 60846.5
Longitude ŽW. X
148841.2 X 148840.3 X 135842.0 X 179819.8 E X 173810.4 E X 162843.9 X 145828.4 X 148843.0 X 146814.5 X 146811.6 X 149827.0 X 152830.7 X 156838.7 X 166832.2 X 145828.4 X 149806.3 X 148842.8 X 148843.0
d 13 C Ž‰.
Description
y24.8 y24.3 y23.5 y23.4 y22.8 y22.7 y22.3 y24.2 y27.2 y27.7 y28.1 y27.1 y29.6 y29.1 y29.1 y29.3 y29.4 y29.4
Street pavement, ) 20 years old Driveway paved before 1964 Old section of airport runway World War II C airport runway Old deactivated airport runway End of old airport runway Active runway at main airport Tar with gravel in riprap near gravel runway New airport runway Road to Valdez Glacier, paved in 1970s New airport runway Navy terminal parking pad North apron of airport runway New airport runway Tar spilled adjacent to active runway Parking pad for small planes Newly surfaced road to railroad portal Tar chunks in riprap near end of runway
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Table 4 Carbon isotopic compositions Ž d 13 C‰. of natural seeps and oil, Gulf of Alaska Sample no.
Location
Natural seeps and oil, Gulf of Alaska 93-27 Katalla 93-28 Samovar Hills 93-29 Johnston Cr. 95-2 Katalla
Latitude ŽN. X
60812.0 X 60807.5 X 60801.7 X 60811.2
Longitude ŽW. X
144825.0 X 140846.0 X 141853.3 X 144825.3
parently representing new pavements, and of Exxon Valdez residues, which have a North Slope crude oil source Žcompare Fig. 2D and Fig. 2A.. 3.4. Intermediate source of Monterey-Californiasourced residues The purpose of determining the carbon isotopic compositions of these various oil products was to try to narrow down the intermediate source or sources of the Monterey-California-sourced residues in Prince William Sound. The sources need to have very uniform carbon isotopic compositions, and the sources need to have been rather large in order to have impacted such a large part of the sound. Fuel oils and asphalt are the best candidates. The carbon isotopic compositions of fuel oils and asphalt from old town Valdez, fuel oil at the abandoned cannery on McClure Bay, and the oil from storage tanks at Port Ashton are in the appropriate range to account for most of the Monterey-California-sourced residues Žcompare Fig. 2B and Fig. 2A.. Mining fluids on Latouche Island with compositions ranging from y24.3 to y24.8‰ are isotopically too light to be considered a likely source. Likewise, natural seeps and oil from the Gulf of Alaska ŽTable 4; Fig. 2E. are isotopically too light Žy24.7 to y26.4‰., although these oils may contribute to the hydrocarbon background in the sediment within the sound ŽPage et al., 1995.. Of the three sites, the old town of Valdez is the only one where large quantities of fuel oil and asphalt products were spilled during the Great Alaska Earthquake of 1964 ŽWilson and Tørum, 1972.. At least two or three tanks w10 4-barrel capacity each Ž1 barrel s 42 US gallonss 160 l.x ruptured ŽJ. Kelsey, personal communication, 1995. spilling at most about 3 = 10 4 barrels of fuel oil, about 12% of the amount released during the Exxon
d 13 C Ž‰.
Description
y25.4 y26.4 y25.9 y24.7
Composite oil sample from well Oil from Sec. 3, T21S, R27E Oil from Sec. 7, T22S, R21E Oil seeping from soil down slope below oil rig
Valdez spill of 1989 Ž2.6 = 10 5 barrels.. The tanks were still leaking four years after the earthquake, but the total amount of fuel oil and asphalt that actually entered the sound as a result of the earthquake will never be known because complete records were not kept. The average carbon isotopic composition of the tar mats at the sites of fuel oil and asphalt storage at the old town of Valdez of y23.5 " 0.1 Ž n s 3. is heavier by slightly less than 0.3‰ than the average of 60 Monterey-California-sourced residues of y23.8 " 0.1‰ Ž n s 60; range from y23.5 to y24.1‰.. It is believed that most of the MontereyCalifornia-sourced residues found in Prince William Sound came from fuel oil and asphalt spilled at the old town of Valdez during the 1964 earthquake. The slight difference in carbon isotopic compositions of the postulated source and the resultant residues may be due to more intense weathering of the small Monterey-California-sourced tar balls, dispersed throughout the northern and western parts of the sound, than to weathering of the less vulnerable tar mats on the beach at old Valdez. 4. Summary Oil products used in the developmental history of Alaska, and particularly of the region of Prince William Sound, have a broad range of carbon isotopic compositions, ranging from y22.3 to y29.6‰, with older products Žpre ; 1970. being isotopically heavier and newer products Žafter ; 1970. being isotopically lighter. The reason for the isotopically heavy older products is that they were refined from crude oils with unusually heavy carbon isotopic compositions, generated from source rocks of the Miocene Monterey Formation of California. The
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economic growth of Alaska from the early 1900s to ; 1970 was supported by oil products shipped more cheaply from California than could be produced locally in Alaska. These products were used in various ways such as for fuel, lubrication, construction, and paving. After North Slope crude oil became available in the 1970s, Alaska had more than enough oil to satisfy its economic needs, and oil products shipped from California became much less important. The carbon isotopic compositions of various oil products reflect this change of source from California to Alaska. In addition, on the shorelines of Prince William Sound oil residues can be found from two distinct sources—one in California and the other in Alaska. Alaska ŽNorth Slope crude oil. and the Exxon Valdez oil spill of 1989 are the main source and cause, respectively, of the Exxon Valdez residues. On the other hand, California is the source of the Monterey-California-sourced crude oil, and the Great Alaska Earthquake of 1964 caused its dispersal leading to the Monterey-California-sourced residues. Carbon isotopic comparisons outlined in this paper
suggest that many of the Monterey-Californiasourced residues Žflattened tar balls. came from fuel oil and asphalt, stored in tanks in old town Valdez that were ruptured during the 1964 earthquake, spilling these oil products into the waters of Prince William Sound. Acknowledgements We are grateful to the following people who willingly shared their recollections about oil product usages and occurrence in Alaska: Nancy Lethcoe, Jim Lethcoe, Bill Wyatt, James Williams, Del Webb, Bob Felland, and John Kelsey of Valdez; Linda Hyce and John Labowe of Whittier; Janice Reeve Ogle, Brad Phillips, and L.J. Evans of Anchorage, Larry Evanoff of Chenega Bay; Bill Stokes of Bethel, and Ted Bence of Houston, Texas. Transportation to the sampling sites was accomplished by small boats from NOAA ships MacArthur and Rainier, Alaska Wilderness Sailing Safaris Arctic Tern II, and the USGS RrV Karluk, and by ERA helicopter. Tom Lorenson helped in the preparation of the graphics.
Appendix A. Compilation of carbon isotopic compositions ( d 13 C‰ ) of oil-like residues in Prince William Sound, Alaska— Exxon Valdez residues, Monterey-California-sourced residues, and Exeptions
Sample no.
Location
Latitude ŽN .
Exxon Valdez residues 90-6 Elrington I. 90-18 Knight I. 90-19 Smith I. 90-29 Eleanor I. 90-41 Naked I. 92-22 Knight I.
59858.2 X 60827.6 X 60831.7 X 60834.1 X 60839.4 X 60814.2
92-26
Knight I.
60815.7
92-28 93-9B 93-12B 93-13B 93-13C 93 y 14A 93-15B 93-16A 93-16C 93-18B 93-26B 93-30
Evans I. Ingot I. Knight I. Chenega I. Chenega I. Granite Cove Point Nowell Eshamy Bay Eshamy Bay Culross I. Green I. Knight I.
60806.5 X 60831.9 X 60827.5 X 60822.8 X 60822.8 X 60825.1 X 60826.5 X 60827.9 X 60827.9 X 60838.5 X 60817.6 X 60809.8
Longitude ŽW .
X
148810.5 X 147843.4 X 147822.6 X 147834.4 X 147822.9 X 147843.5
X
X
147846.2
X
147857.7 X 147837.7 X 147842.6 X 148800.5 X 148800.5 X 147857.7 X 147856.2 X 147857.6 X 146857.6 X 148807.0 X 147824.5 X 147845.4
X
X
d 13 C Ž‰ .
Description
y29.3 y29.2 y29.4 y29.1 y29.4 y29.5
Oiled sediment, high tide line, inner bay Oily sand, Herring Bay Oiled cobbles, north side of island Solid oil on rock, Northwest Bay Oiled cobbles, McPherson Bay Oily fissile shale, south arm, Snug Harbor Solid oiled mat, North arm, Snug Harbor Solid oiled mat, Shelter Bay Solid oiled mat, archaeological site Solid oiled mat, Herring Bay Sticky tar in cracks of rock, north end Semi-sticky tar on rock Semi-sticky tar on rock and in crack Oily matted organic debris Weathered tar-cemented barnacles Tar matted organic debris Sticky oil among beach cobbles Tar-like residue on rock Oily pebbles, Point Helen
y29.4 y29.3 y29.6 y29.4 y29.8 y29.3 y29.2 y29.4 y29.3 y29.3 y29.3 y29.2 y29.4
K.A. KÕenÕolden et al.r Chemical Geology 152 (1998) 73–84 X
147850.4 X 147850.4 X 147850.4 X 147850.5 X 147853.4
60806.7
X
147853.4
60806.7
X
147853.4
94-2A 94-2B 94-2C 94-2D 94-5A
Latouche I. Latouche I. Latouche I. Latouche I. Evans I.
60803.9 X 60803.9 X 60803.9 X 60803.9 X 60806.7
94-5B
Evans I.
94-5D
Evans I.
X
X
X
147835.0 X 148811.0 X 152821.9 X 152839.0
X
153854.3
X
148810.5 X 147824.7 X 146847.7 X 147819.9 X 147820.7 X 147821.3 X 147846.1 X 147858.0 X 147809.0 X 147834.0 X 147835.5 X 147823.0 X 147826.5 X 146820.1 X 146819.9 X 146826.2 X 146826.0 X 146833.9 X 146838.5 X 146838.5 X 146841.6 X 146841.6 X 147823.9 X 147837.7 X 147837.7 X 147837.7 X 147836.5 X 147842.6 X 148800.5 X 147857.7 X 147857.7 X 147857.7 X 147856.2 X 147856.2 X 147857.6 X 147857.6 X 147856.5 X 148807.0 X 147852.6 X 147844.9 X 147806.8 X 147806.8 X 147808.8 X 147809.0 X 147840.2
94-13 95-13 95-52 95-56
Unakwik Inl. Elrington I. Shuyak I. Shuyak I.
60852.8 X 59858.5 X 58838.0 X 58833.9
95-58
Kodiak I.
57842.4
Monterey-California-sourced residues 90-6A Elrington I. 90-37A Storey I. 92-5 Valdez Arm 92-16 Naked I. 92-18C Naked I. 92-20 Green I. 92-25 Knight I. 92-29 Evans I. 92-35 Glacier I. 92-36B Olsen I. 92-37 Olsen Cove 92-38 Naked I. 92-39 Naked I. 92-40 Valdez Harb. 92-41 Valdez Harb. 93-1 Port Valdez 93-3 Port Valdez 93-4 Port Valdez 93-5 Valdez Narr. 93-6 Valdez Narr. 93-7A Valdez Arm 93-7B Valdez Arm 93-8 Peak I. 93-9A Ingot I. 93-10A Ingot I. 93-10B Ingot I. 93-11 Block I. 93-12A Knight I. 93-13A Chenega I. 93-14B Granite Cove 93-14C Granite Cove 93-14E Granite Cove 93-15A Point Nowell 93-15D Point Nowell 93-16B Eshamy Bay 93-16D Eshamy Bay 93-17A Crafton I. 93-18A Culross I. 93-20 Perry I. 93-21 Lone I. 93-22A Growler I. 93-22B Growler I. 93-23A Glacier I. 93-23B Glacier I. 93-24 Disk I.
X
59858.2 X 60843.9 X 61800.0 X 60840.3 X 60840.6 X 60818.2 X 60815.8 X 60806.5 X 60854.0 X 60852.2 X 60852.1 X 60839.0 X 60842.0 X 61807.6 X 61807.7 X 61805.3 X 61805.2 X 61804.7 X 61804.3 X 61804.3 X 60859.5 X 60859.5 X 60842.3 X 60831.9 X 60832.0 X 60832.0 X 60831.9 X 60827.5 X 60822.8 X 60825.1 X 60825.1 X 60825.1 X 60826.5 X 59826.5 X 60827.9 X 60827.9 X 60830.5 X 60838.5 X 60842.8 X 60841.8 X 60854.1 X 60854.1 X 60854.3 X 60854.0 X 60829.3
X
X
X
y29.3
Live oil on pebbles, Sleepy Bay Oil patina on cobble, Sleepy Bay Oil mat-like pavement, Sleepy Bay Oil cemented pebbles, Sleepy Bay Sticky oil on pebbles, near Bishop Rock Oil in pocket of rock, near Bishop Rock Tar with needles on rock, near Bishop Rock Sticky tar patch, Mueller Cove Tar cemented sand Oily pebbles from beach, Point Banks Oily pebbles from beach, west side of island Oily pebbles from beach, Chief Point
y23.8 y23.9 y23.7 y23.7 y23.8 y23.8 y23.8 y23.7 y23.8 y23.8 y23.8 y23.9 y23.9 y24.0 y23.6 y23.6 y23.7 y23.7 y23.7 y23.7 y23.8 y23.7 y23.8 y24.0 y23.7 y23.8 y23.7 y23.9 y24.3 y23.7 y23.7 y23.5 y23.8 y23.7 y23.6 y23.7 y23.7 y23.8 y23.8 y23.7 y23.7 y23.7 y23.6 y23.7 y23.7
Tar on rock, inner bay Tar on cobble, north side of island Tar on rock, east side of Valdez Arm Tar on rocks, McPherson Bay Tar on rocks, point east of McPherson Bay Tar on rock, northeast end of island Tar on rock, North arm, Snug Harbor Tar on rock, Shelter Bay Tar on rock, Eagle Bay Tar on rock, Exxon Site 6 Tar on rock, Exxon Site 7 Tar on metashale, Bass Harbor Matted tar on northern point of island Tar on rock, Outer Point Tar on rock, Dock Point Tar mat at Salmon Creek Tar mat near Salmon Creek Tar on rocks, Anderson Bay Tar on rock, east side Tar mat cementing rock, east side Tar on rock, east side Sticky tar mat, east side Soft tar on rock, north shore Tar on rock, archaeological site Soft tar on beach, north side Hard tar on beach, north side Sticky tar on cobble beach Tar on rocks, Herring Bay Sticky tar on rock Tar on rock, north end Sticky tar on rock, north end Lusterous tar on rock, north end Sticky tar on rock Tar on rock Sticky tar on beach, south entrance Soft tar on beach, south entrance Tar on rock, west side of north point Sticky tar on rocks, southeast side Tar on rocks, east side Sticky tar on rocks, north shore Tar on cobbles Tar cemented conglomerate Tar on rock, Elder Bay Tar on rock, Eagle Bay Žsame as 92-35 . Tar on rock
y29.5 y29.3 y29.4 y29.4 y29.4 y29.5 y29.3 y29.4 y29.1 y29.3 y29.3
83
K.A. KÕenÕolden et al.r Chemical Geology 152 (1998) 73–84
84 Sample no.
Location
Latitude ŽN .
93-25 93-26A 94-2E 94-2F 94-5C 94-6A 94-6B
Ingot I. Green I. Latouche I. Latouche I Evans I. Squire I. Squire I.
60830 X 60817.6 X 60804.0 X 60804.0 X 60806.7 X 60814.9 X 60814.9
147838 X 147825.8 X 147850.5 X 147850.5 X 147853.4 X 147856.8 X 147856.8
94-6C 94-7 94-8 94-10
Squire I. Valdez Arm. Perry I. W. Eickel. B.
60814.9 X 61802.5 X 60843.5 X 60853.9
X
147856.8 X 146847.4 X 147858.0 X 147819.6
94-11 94-12 94-14 94-15 94-18A
Glacier I. N., Flent Pt. Naked I. N., Elf Pt. Buyers Cove
60852.9 X 60856.6 X 60839.3 X 60856.8 X 60855.2
X
147818.1 X 147808.2 X 147826.4 X 147803.0 X 147816.7
95-8A 95-14 95-15 95-29
Ellamar Ingot I. Eleanor I. Perry I.
60853.7 X 60830.0 X 60833.8 X 60841.1
X
146842.1 X 147838.7 X 147834.5 X 147855.2
Exceptions 92-19 93-19
Green I. Culross I.
60818.2 X 60844.9
X
147821.3 X 148810.7
X
Longitude ŽW . X
X
X
X
X
References Hostettler, F.D., Kvenvolden, K.A., 1994. Geochemical changes in crude oil spilled from the Exxon Valdez supertanker into Prince William Sound, Alaska. Organic Geochemistry 21, 927–936. Kvenvolden, K.A., Hostettler, F.D., Rapp, J.B., Carlson, P.R., 1993a. Hydrocarbons in oil residues on beaches of islands of Prince William Sound. Marine Pollution Bulletin 26, 24–29. Kvenvolden, K.A., Carlson, P.R., Threlkeld, C.N., Warden, A., 1993b. Possible connection between two Alaskan catastrophes occurring 25 yr apart Ž1964 and 1989.. Geology 21, 813–816. Kvenvolden, K.A., Hostettler, F.D., Carlson, P.R., Rapp, J.B., Threlkeld, C.N., Warden, A., 1995. Ubiquitous tar balls with a California-source signature on the shorelines of Prince William Sound, Alaska. Environmental Science and Technology 29, 2684–2694. Lethcoe, J., Lethcoe, N., 1994. A History of Prince William Sound, Alaska. Prince William Sound Books, Valdez, AK.
d 13 C Ž‰ .
Description
y23.7 y23.9 y23.8 y24.1 y23.8 y23.7 y23.7
y22.4 y23.6 y24.1 y22.3
Tar on rock, southwest side Tar on rock, north shore Tar on log at storm berm, Sleepy Bay Tar on rock, Sleepy Bay Tar on rock, near Bishop Rock Tar with old needles on rock, west side Tar with new needles on rock, west side Tar on rocks, west side Tar on rock, Sawmill Bay Scatter tar on boulders, West Twin Bay Tar on rock, mainland side, Glacier Passage Tar on rock, Irish Cove Tar on wood at high tide, W. Columbia Bay Tar on rock, Cabin Bay Tar on large rock, near Columbia Bay Tar on rock, mainland side, Glacier Passage Tar cobble on beach Tar cemented cobbles Tar on rock Tar on rock at wharf site
y26.6 y27.8
Oil on rock, northeast end of island Sticky oil on rock, Culross Bay
y23.7 y23.7 y23.8 y23.7 y23.7 y23.7 y23.6 y22.8 y23.7
Page, D.S., Boehm, P.D., Douglas, G.S., Bence, A.E., 1995. Identification of hydrocarbon sources in benthic sediments of Prince William Sound and the Gulf of Alaska following the Exxon Valdez oil spill. In: Wells, P.G., Butler, J.N., Hughes, J.S. ŽEds.., Exxon Valdez Oil Spill: Fate and Effects in Alaska Waters, ASTM STP 1219, American Society for testing and Materials, Philadelphia, pp. 41–83. Standard Oil of California, 1979. 1879–1979, One Hundred Years Helping to Create the Future. Standard Oil of California. White, G.T., 1962. Formative Years in the Far West—A History of Standard Oil of California and Predecessors through 1919. Appleton–Century–Crofts, New York. Wilson, B.W., Tørum, A., 1972. Effects of the tsunamis: an engineering study. In: The Great Alaska Earthquake of 1964, Oceanography and Coastal Engineering. National Research Council, National Academy of Sciences, Washington, DC, pp. 361–523.
Carbon isotopic comparisons of oil products used in the developmental history of Alaska Keith A. Kvenvolden a,) , Paul R. Carlson a , Augusta Warden b, Charles N. Threlkeld b a b
U.S. Geological SurÕey, 345 Middlefield Road, MS 999, Menlo Park, CA 94025, USA U.S. Geological SurÕey, Federal Center, Box 25046, MS 977, DenÕer, CO 80225, USA
Abstract Studies of the fate of oil released into Prince William Sound, AK, as a result of the 1989 Exxon Valdez oil spill, have led to an unexpected discovery. In addition to oil-like residues attributed to the spill, the ubiquitous presence of flattened tar balls, the carbon isotopic compositions of which fall within a surprisingly narrow range w d 13 C PDB s y23.7 " 0.3‰ Ž n s 65.x, were observed on the shorelines of the northern and western parts of the sound. These compositions are similar to those of some oil products wy23.7 " 0.7‰ Ž n s 35.x that were shipped from California and used in Alaska for fuel, lubrication, construction, and paving before ; 1970. These products include fuel oil, asphalt, and lubricants wy23.8 " 0.5‰ Ž n s 11.x, caulking, sealants, and roofing tar wy23.7 " 0.7‰ Ž n s 16.x, and road pavements and airport runways wy23.5 " 0.9‰ Ž n s 8.x. Fuel oil and asphalt wy23.5 " 0.1‰ Ž n s 3.x, stored at the old Valdez town site and spilled during the 1964 Alaskan earthquake, appear to be the source of most of the beached tar balls. Oil products with lighter carbon isotopic compositions, between y25 and y30‰ Ž n s 18., appear to have been used more recently in Alaska, that is, after ; 1970. The source of some of the products used for modern pavement and runways wy29.3 " 0.2‰ Ž n s 6.x is likely Alaskan North Slope crude oil, an example of which was spilled in the 1989 oil spill wy29.2‰ Ž n s 1.x. q 1998 Elsevier Science B.V. All rights reserved. Keywords: Alaska; Exxon Valdez; Alaskan North Slope crude oil; Fuel oil; Carbon isotopic comparisons
1. Introduction Following the 1989 Exxon Valdez oil spill in Prince William Sound, AK, a multi-year program was begun to assess the geological fate and impact of the spilled Alaskan North Slope crude oil. Starting in 1990 and continuing in 1992–1996, oil-like residues from the shorelines throughout the sound were collected and analyzed. In a preliminary geo)
Corresponding author
chemical study of eight of the first samples collected, it was discovered that six of the samples were weathered residues of North Slope crude oil, most likely spilled from the Exxon Valdez supertanker. Two flattened tar ball samples, however, had molecular and carbon isotopic characteristics of a crude oil source in the Miocene Monterey Formation of California ŽKvenvolden et al., 1993a.. These two samples came from localities about 100 km apart on Storey Island and Elrington Island ŽFig. 1a.; this observation led to the conclusion that oil residues
0009-2541r98r$ - see front matter q 1998 Elsevier Science B.V. All rights reserved. PII: S 0 0 0 9 - 2 5 4 1 Ž 9 8 . 0 0 0 9 7 - 7
74 K.A. KÕenÕolden et al.r Chemical Geology 152 (1998) 73–84
Fig. 1. Prince William Sound area and southern Alaska, showing locations of oil residues and oil products. Ža. Exxon Valdez oil and residues Žtriangles., Monterey-Californiasourced residues Žsquares. and exceptions Žcircles. from Appendix A. Žb. Oil products used in the area of Prince William Sound Ždiamonds.. Sample numbers Žlast digit of year-number.. Data from Table 1, Table 2 and Table 3. Abbreviations are: E, Ellamar; GM, Granite Mine; MB, McClure Bay; N, Nuchek; PB, Pigot Bay; PC, Passage Canal; PNJ, Port Nellie Juan; PW, Port Wells; SC, Shotgun Cove. Žc. Oil products used in southern Alaska Ždiamonds. and natural seeps and oil in the Gulf of Alaska Žpentagons.; Exxon Valdez residues Žtriangles.. Sample numbers Žlast digit of year-number.. Data from Table 1, Table 3 and Table 4. Abbreviations are: Am, Amchitka; At, Attu; B, Bethel; CB, Cold Bay; Ch, Chilkat; Co, Cordova; DH, Dutch Harbor; G, Gustavus; Ka, Katalla; Ko, Kodiak Is.; KS, King Salmon; P, Palmer; S, Seward; Sh, Shuyak Is.; V, Valdez; W, Whittier.
K.A. KÕenÕolden et al.r Chemical Geology 152 (1998) 73–84
75
Fig. 1 Žcontinued..
with similar geochemical characteristics could be present on many other shorelines of the Sound. This conclusion was verified when, on the basis of carbon isotopic and biomarker characteristics of 61 samples from widely dispersed localities, it was shown ŽKvenvolden et al., 1993b, 1995. that probable Monterey-California-sourced, oil-like residues are ubiquitous on the shorelines of the northern and western parts of Prince William Sound ŽFig. 1a.. The inventory of oil-like residues from the shorelines of Prince William Sound Žanalyzed for carbon isotopic compositions—Appendix A. now contains 31 samples of Alaskan North Slope crude oil Žlikely Exxon Valdez residues., 65 samples of probable Monterey-California-sourced residues, and only two exceptions from unknown sources ŽFig. 2A; sample locations in Fig. 1a.. Analyses of carbon isotopic compositions Žreported in ‰ values relative to the Peedee belemnite ŽPDB. standard. indicate that the average carbon isotopic composition of the suite of 31 residues Žy29.3 " 0.1‰. is not significantly different from the isotopic composition of the oil spilled
from the Exxon Valdez supertanker Žy29.2‰; Table 1, sample 89-0.. Thus, the 31 residues are referred to as Exxon Valdez residues, although it is possible, but not likely, that some of these residues could be from other minor spills of North Slope crude oil. Biomarker data on 25 of these samples support the connection with the Exxon Valdez spill ŽHostettler and Kvenvolden, 1994; Kvenvolden et al., 1995.. The supertanker carried a mixed load of Alaskan North Slope crude oil; therefore, the ultimate source of Exxon Valdez residues is North Slope oil. The 65 probable Monterey-California-sourced residues have uniquely heavy carbon isotopic compositions of y23.7 " 0.3‰. The carbon isotopic compositions of all of these samples and biomarker analyses ŽKvenvolden et al., 1995. of 38 of these same samples clearly show a correlation with geochemical properties of crude oils from Miocene Monterey Formation source rocks of California ŽKvenvolden et al., 1993a,b, 1995.. Thus, although the ultimate source of the 65 residues is in California, the intermediate source or sources is still uncer-
76
K.A. KÕenÕolden et al.r Chemical Geology 152 (1998) 73–84
Fig. 2. Histograms of carbon isotopic compositions Ž d 13 C‰. of oil residues and oil products in Alaska. ŽA. Oil-like residues on shorelines of Prince William Sound. ŽB. Fuel oils, asphalt, and lubricants. ŽC. Caulking, sealants, and roofing tar. ŽD. Road pavements and airport runways. ŽE. Natural seeps and oil, Gulf of Alaska.
K.A. KÕenÕolden et al.r Chemical Geology 152 (1998) 73–84
77
Table 1 Carbon isotopic compositions Ž d 13 C‰. of fuel oils, asphalt, and lubricants used in Alaska Sample no.
Location
Fuel oils, asphalt, and lubricants 92-6 Old Valdez 92-30 Latouche I. 92-31 Latouche I. 94-3A Evans I. 94-4 Evans I. 94-19 Bethel 95-11B Old Valdez 95-11C Old Valdez 95-19 McClure Bay 95-21 McClure Bay 95-22 McClure Bay 89-0 Bligh Reef 95-23A P. Nellie Juan 95-37 Granite Mine
Latitude ŽN. X
61807.0 X 60803.2 X 60803.2 X 60804.0 X 60803.5 X 60847.5 X 61806.8 X 61806.8 X 60832.9 X 60832.9 X 60832.9 X 60851.3 X 60835.5 X 60858.0
Longitude ŽW. X
146816.5 X 147854.1 X 147854.1 X 148800.5 X 148803.2 X 161845.0 X 146816.0 X 146816.0 X 148809.9 X 148809.9 X 148809.9 X 146852.5 X 148806.7 X 148812.3
tain. In order to explore possible intermediate tain. In order to explore possible intermediate sources, we undertook a survey of various oil products used in Alaska with emphasis on older products which were used before Alaska obtained its own internal crude oil supply after ; 1970. This paper examines the carbon isotopic compositions of Ž1. fuel oils, asphalt, and lubricants, Ž2. caulking, sealants, and roofing, and Ž3. road pavements and airport runways. In addition, we report on the carbon isotopic compositions of natural seeps and oil in the Gulf of Alaska. 2. Methods Oil-like residues were collected from beaches, mainly at the high tide line, by removing the flattened tar balls from rock surfaces with a pre-cleaned knife, wrapping the sample in pre-cleaned aluminum foil, and storing the wrapped sample in a labeled sack. Oil products were removed from various structures and surfaces using a pre-cleaned knife and stored in the same manner as the oil-like residues. In the laboratory, the oil-like residues and oil products were dissolved in dichloromethane, and the resulting solutions were filtered through glass wool and concentrated to remove the solvent; a portion Ž40–90 mg. of each extract was then recovered for determination of carbon-isotopic composition. For this determination, at least 4 mg of each extract was placed in
d 13 C Ž‰.
Description
y23.6 y24.8 y24.3 y24.3 y23.4 y23.3 y23.5 y23.4 y23.7 y23.8 y23.7 y29.2 y27.7 y25.3
Tar mat, site of fuel and asphalt storage plants Tar in mine dump Oil at toe of mine dump Sticky oily mat in dump, Chenega Bay Tar from storage tank, Port Ashton Asphalt from leaking storage drum Tar on cobble, site of fuel and asphalt storage Tar mat, site of fuel and asphalt storage plants Oil on abandoned equipment on beach Oil in valve of cannery fuel oil storage tank Tar on rock below cannery oil storage tank North Slope crude oil in Exxon Valdez Motor oil in cabin, south of entrance Grease in storage drum on beach
an evacuated quartz tube with cupric oxide, as a source of oxygen, and a strip of silver metal, as a catalyst, and combusted to 8408C. The resulting CO 2 was purified under vacuum by differential temperature transfer and measured by isotope-ratio mass spectrometry. The results are reported in delta Ž d . notation in parts per thousand Ž‰. relative to the PeeDee Belemnite ŽPDB. standard; accuracy of duplicate analyses is 0.1‰. 3. Results and discussion In the historical development of the economy of Alaska, California has served as a principal source of oil products since the early part of the 20th century. Oil products were shipped commonly by barge from ports such as El Segundo and Richmond in California ŽWhite, 1962; Standard Oil of California, 1979. to ports such as Whittier on the west edge and Valdez at the north end of Prince William Sound, where fuel oil and asphalt have been stored and distributed. Although Alaskan crude oil was produced at Katalla on the Gulf of Alaska from 1904 to 1933, it was not until North Slope crude oil, discovered at Prudhoe Bay in 1968, reached the Valdez terminal in 1977 that Alaska had a sufficient supply of oil to satisfy even more than its own economic needs. Since then, California oil products have become much less significant. In the following discus-
78
K.A. KÕenÕolden et al.r Chemical Geology 152 (1998) 73–84
sions the historical aspects related to our various samples are taken mainly from Lethcoe and Lethcoe Ž1994.. 3.1. Fuel oils, asphalt, and lubricants Carbon isotopic compositions were measured on 14 oil products representing currently or previously stored fuel oils, asphalt, and lubricants ŽTable 1; Fig. 1b, Fig. 2B.. Eleven of these samples have an average carbon isotopic composition of y23.8 " 0.5‰, similar to the average composition of MontereyCalifornia-sourced residues Žy23.7 " 0.3‰.. At sites of fuel oil and asphalt storage facilities in the old town of Valdez, three samples of tar Žy23.5 " 0.1‰. were collected which are believed to represent the oil products stored at the time of the 1964 Great Alaska Earthquake. This earthquake destroyed the old town of Valdez and caused fuel and asphalt to spill into the fjord of Port Valdez at the north end of Prince William Sound ŽWilson and Tørum, 1972.. Fuel oil had been stored at the old town of Valdez since at least the 1940s, and an asphalt plant was built there in 1952. These facilities were removed sometime after 1964. McClure Cannery, located on McClure Bay, Port Nellie Juan, ŽFig. 1b. is now abandoned. This cannery was first opened in 1917 and ceased major operations in 1959. At the abandoned ruins we found three samples of fuel oil Žy23.7 " 0.1‰. associated with a small supply tank at the old power plant. Small quantities of oil are still leaking into the Sound. On Evans Island ŽFig. 1. fuel oil Žy23.4‰. was sampled from abandoned tanks at Port Ashton, and sticky oil Žy24.3‰. was collected from a dump at Chenega Bay. Port Ashton was a major center for herring processing from 1914 into the 1930s; the dump at Chenega Bay was the site at which a storage tank once stood as part of an old saltery or cannery. Tar Žy24.3‰. and oil Žy24.8‰. associated with a mine dump were sampled on Latouche Island ŽFig. 1b. where these oil products have apparently been used in ore separation processes. Mining of copper began here in 1897 and continued on and off until 1938. Some new mining activity is again taking place there. The last sample of this isotopically heavy group of 14 samples was obtained from a leaking storage drum of asphalt Žy23.3‰. that was
washed into the Kuskokwim River near Bethel, Alaska ŽFig. 1c.. As many as 3000 to 4000 drums of asphalt were buried at the site of a military airport constructed between 1941 and 1943. The asphalt was originally intended for paving the runway. These drums and their contents now represent a serious environmental hazard. Three samples were found with carbon isotopic compositions lighter than y25‰. These include a sample of crude oil from the supertanker Exxon Valdez Žy29.2‰., the source of Exxon Valdez residues on shorelines of Prince William Sound, a sample of grease Žy25.3‰. in a storage drum washed above the beach near the Granite Mine site ŽFig. 1b. where a gold mine once existed, and a sample of Chevron SAE 30 motor oil Žy27.7‰. found in an abandoned cabin on the south side of the entrance to Port Nellie Juan ŽFig. 1b.. These samples represent post ; 1970 stored oil products used in Alaska. 3.2. Caulking, sealants, and roofing tar Table 2 lists 21 samples of oil products used in Alaska in various aspects of construction. Sixteen of these samples have an average carbon isotopic composition of y23.7 " 0.7‰, with samples falling in a range similar to the old fuel oils, asphalt, and lubricants and the Monterey-California-sourced residues Žcompare Fig. 2C with Figs. 2B and 2A.. A cannery, started in 1924 by the Pacific American Company near Cannery Creek in Unakwik Inlet ŽFig. 1b. and abandoned sometime after 1936, yielded two samples—caulking on a beam Žy23.0‰. and tar paper from a roof. The tar paper sample was extracted with dichloromethane, and the carbon isotopic composition of the recovered extract was measured Žy23.3‰.. Other tar paper samples were treated similarly. Tar was collected at two different sites on Latouche Island ŽFig. 1b.; one sample of tar Žy23.6‰. was found on a telephone pole near a mine dump on the northwest side of the island, and caulking Žy23.8‰. was obtained from a log on a storm berm in Sleepy Bay. Tar on pilings of an abandoned wharf Žy23.6‰. and tar sealant on a metal roof of a ruined building Žy23.8‰. were recovered at the cannery on McClure Bay that was discussed previously. Ellamar ŽFig. 1b. was the site
K.A. KÕenÕolden et al.r Chemical Geology 152 (1998) 73–84
79
Table 2 Carbon isotopic compositions Ž d 13 C‰. of caulking, sealants, and roofing tar used in construction in Prince William Sound, AK Sample no.
Location
Caulking, sealants, and roofing 92-3 Whittier 92-32 Latouche I. 94-2E Latouche I. 94-16 Unakwik Inl. 94-17 Unakwik Inl. 95-4 Chilkat 95-5 Chilkat 95-7 Nuchek 95-8B Ellamar 95-9 Ellamar 95-17 McClure Bay 95-20 McClure Bay 95-24 Shotgun Cove 95-25 Shotgun Cove 95-31 Perry I. 95-32 Pigot Bay 95-10 Old Valdez 95-30 Perry I. 95-34 Pigot Bay 95-38 Granite Mine 95-39 Esther I.
Latitude ŽN. X
60846.5 X 60803.2 X 60804.0 X 61800.5 X 61800.5 X 60811.3 X 60811.3 X 60820.0 X 60853.7 X 60853.7 X 60832.9 X 60832.9 X 60847.8 X 60847.8 X 60841.1 X 60850.5 X 61806.9 X 60841.1 X 60850.4 X 60858.3 X 60848.0
Longitude ŽW. X
148840.3 X 147854.1 X 147850.6 X 147831.5 X 147831.5 X 144813.0 X 144813.0 X 146839.5 X 146842.1 X 146842.1 X 148809.9 X 148809.9 X 148831.8 X 148831.8 X 147855.2 X 148819.4 X 146816.2 X 147855.2 X 148823.2 X 148811.9 X 148805.0
of a copper mine from 1900 to 1929 and then a cannery that closed about 1955. A sample of tar from the piling of an abandoned wharf Žy23.4‰. and a sample of tar binding a cable on the boat pier Žy23.3‰. were collected here. At the former site of Chilkat on the Bering River ŽFig. 1c., samples were obtained of tar on chimney flashing Žy22.9‰. and of tar paper from a collapsed cabin Žy22.9‰.. Other isotopically heavy Ž) y25‰. construction tars were found on a timber on the beach at Nuchek Žy24.0‰. on Hinchinbrook Island and on a plank above the beach at Pigot Bay Žy23.7‰. on the west side of the entrance to Port Wells ŽFig. 1b.. On Perry Island ŽFig. 1b., an oyster farm has taken the place of the South Perry Island Fox Farm which closed in 1945. Tar on a boat shed support here has a carbon isotopic composition of y24.8‰. The St. Elias Ocean Products floating cannery, operating since 1964, was beached in a storm and abandoned in 1979 in Shotgun Cove on the south side of Passage Canal ŽFig. 1b.. Two tar samples were collected from this wreck–tar on metal roofing Žy24.8‰. and tar impregnated roofing fabric Žy22.9‰.. In the
d 13 C Ž‰.
Description
y24.9 y23.6 y23.8 y23.3 y23.0 y22.9 y22.9 y24.0 y23.4 y23.3 y23.6 y23.8 y24.8 y22.9 y24.8 y23.7 y29.3 y28.7 y25.4 y26.0 y27.3
Tar roofing from Buckner Building Tar on telephone pole at mine dump Tar on log, Sleepy Bay Tar paper on roof at abandoned cannery Tar on beam at abandoned cannery Tar on chimney flashing of ruined building Tar paper from ruined building Tar on timber on beach Tar on piling of abandoned wharf Tar on cable binding on pier Tar on piling of abandoned wharf Tar on metal roofing of ruined building Tar on metal roofing of abandoned barge Tar coating of roof fabric of abandoned barge Tar on support for boat shed Tar on plank above the beach Tar in hold of wreck of Emerald Pacific Tar on chimney flashing at oyster farm Tar on roof of Forest Service cabin Tar on metal roofing sheets in shed Tar roofing shingle from fish hatchery
town of Whittier ŽFig. 1b and c., the seven story Buckner Building was completed in 1952 but abandoned in 1964 as a result of the earthquake. A sample of roofing tar Žy24.9‰. from this building was analyzed. Most of the samples just discussed have not yet been fractionated and examined for biomarkers. Some samples, especially those from pilings could be creosote, a coal tar product rather than an oil tar material. If any of these samples are actually creosote, then arguments for a California source for these samples are not necessarily valid because coal tars in general have heavy carbon isotopic compositions. Four construction tar samples had carbon isotopic compositions between y25 and y30‰. These samples are tar on chimney flashing Žy28.7‰. near the barn of the oyster farm on Perry Island, sealant on the roof Žy25.4‰. of a modern Forest Service cabin on the south shore of Pigot Bay, tar on metal roofing sheets Žy26.0‰. stored in a small shed above the beach near the site of Granite Mine, and tar from a roof shingle Žy27.3‰. from the Wally Noerenberg Hatchery, built in 1984 on Esther Island ŽFig. 1b..
K.A. KÕenÕolden et al.r Chemical Geology 152 (1998) 73–84
80
The ship Emerald Pacific was beached and abandoned for salvage at the old Valdez town site in 1992. Tar from inside the exposed hold Žy29.3‰. was sampled in May 1995. Surprisingly this tar has the same carbon isotopic composition as Alaskan North Slope crude oil and Exxon Valdez residues ŽFig. 2C and Fig. 2A.. J.T. Williams Žpersonnel communication, 1995., the salvage owner, indicated that the Emerald Pacific had been involved in the cleanup of the Exxon Valdez oil spill. The ship was subsequently damaged, and the tar that was sampled had likely been used to try to plug the leaking hull. 3.3. Road paÕements and airport runways Eighteen examples of pavements and runways were examined for their carbon isotopic compositions ŽTable 3.. Eight of these samples have an average carbon isotopic composition of y23.5 " 0.9‰, values similar to those of old oil products and Monterey-California-sourced residues Žranging from y22.3 to y24.9‰. Žsee Fig. 2.. Street pavements in Whittier near the 14-story Hodge Building Žnow called Begich Towers., which was built in 1956, and near the Buckner Building Žoccupied from 1952 to
1964. were sampled, giving carbon isotopic compositions of y24.8 and y24.3‰, respectively. Tar-cemented gravel near one end of the gravel runway in Whittier measured y24.2‰. Samples of old runways Žsee Fig. 1c for locations. at Gustavus Žy23.5‰., Amchitka Žy23.4‰., Attu Žy22.8‰., Cold Bay Žy22.7‰., and Cordova Žy22.3‰. all have carbon isotopic compositions heavier than y25‰. In contrast, new pavements near Whittier and Valdez have isotopically light compositions of y29.4 and 27.7‰, respectively. Samples of new airport runways ranged from y27.2 to y29.6‰—Valdez Žy27.2‰., Seward Žy28.1‰., Kodiak Žy27.1‰., King Salmon Žy29.6‰., Dutch Harbor Žy29.1‰., and Palmer Žy29.3‰.. Tar, probably used for patching, spilled adjacent to the active runway at Cordova has a composition of y29.1‰, and tar chunks in riprap near the end of the gravel runway in Whittier have a composition of y29.4‰. Within this group, six of the pavement samples, with carbon isotopic compositions ranging from y29.1 to y29.6‰, likely were made of tar produced from North Slope crude oil. This conclusion is based on the similarity of carbon isotopic compositions of these samples, ap-
Table 3 Carbon isotopic compositions Ž d 13 C‰. of road pavements and airport runways in Alaska Sample no.
Location
Latitude ŽN.
Road pavements and airport runways X 92-1 Whittier 60846.3 X 92-4 Whittier 60846.5 X 92-42 Gustavus 58829.0 X 92-45C Amchitka 51823.4 X 92-46C Attu 52849.4 X 92-49B Cold Bay 55812.9 X 95-6B Cordova 60829.6 X 95-28 Whittier 61846.5 X 92-7 Valdez 61807.9 X 92-8 Valdez 61808.6 X 92-34 Seward 60807.7 X 92-43B Kodiak 57845.0 X 92-44C King Salmon 58841.4 X 92-47 Dutch Harbor 53853.8 X 95-6A Cordova 60829.6 X 95-12 Palmer 61835.7 X 95-26 Whittier 60846.5 X 95-27 Whittier 60846.5
Longitude ŽW. X
148841.2 X 148840.3 X 135842.0 X 179819.8 E X 173810.4 E X 162843.9 X 145828.4 X 148843.0 X 146814.5 X 146811.6 X 149827.0 X 152830.7 X 156838.7 X 166832.2 X 145828.4 X 149806.3 X 148842.8 X 148843.0
d 13 C Ž‰.
Description
y24.8 y24.3 y23.5 y23.4 y22.8 y22.7 y22.3 y24.2 y27.2 y27.7 y28.1 y27.1 y29.6 y29.1 y29.1 y29.3 y29.4 y29.4
Street pavement, ) 20 years old Driveway paved before 1964 Old section of airport runway World War II C airport runway Old deactivated airport runway End of old airport runway Active runway at main airport Tar with gravel in riprap near gravel runway New airport runway Road to Valdez Glacier, paved in 1970s New airport runway Navy terminal parking pad North apron of airport runway New airport runway Tar spilled adjacent to active runway Parking pad for small planes Newly surfaced road to railroad portal Tar chunks in riprap near end of runway
K.A. KÕenÕolden et al.r Chemical Geology 152 (1998) 73–84
81
Table 4 Carbon isotopic compositions Ž d 13 C‰. of natural seeps and oil, Gulf of Alaska Sample no.
Location
Natural seeps and oil, Gulf of Alaska 93-27 Katalla 93-28 Samovar Hills 93-29 Johnston Cr. 95-2 Katalla
Latitude ŽN. X
60812.0 X 60807.5 X 60801.7 X 60811.2
Longitude ŽW. X
144825.0 X 140846.0 X 141853.3 X 144825.3
parently representing new pavements, and of Exxon Valdez residues, which have a North Slope crude oil source Žcompare Fig. 2D and Fig. 2A.. 3.4. Intermediate source of Monterey-Californiasourced residues The purpose of determining the carbon isotopic compositions of these various oil products was to try to narrow down the intermediate source or sources of the Monterey-California-sourced residues in Prince William Sound. The sources need to have very uniform carbon isotopic compositions, and the sources need to have been rather large in order to have impacted such a large part of the sound. Fuel oils and asphalt are the best candidates. The carbon isotopic compositions of fuel oils and asphalt from old town Valdez, fuel oil at the abandoned cannery on McClure Bay, and the oil from storage tanks at Port Ashton are in the appropriate range to account for most of the Monterey-California-sourced residues Žcompare Fig. 2B and Fig. 2A.. Mining fluids on Latouche Island with compositions ranging from y24.3 to y24.8‰ are isotopically too light to be considered a likely source. Likewise, natural seeps and oil from the Gulf of Alaska ŽTable 4; Fig. 2E. are isotopically too light Žy24.7 to y26.4‰., although these oils may contribute to the hydrocarbon background in the sediment within the sound ŽPage et al., 1995.. Of the three sites, the old town of Valdez is the only one where large quantities of fuel oil and asphalt products were spilled during the Great Alaska Earthquake of 1964 ŽWilson and Tørum, 1972.. At least two or three tanks w10 4-barrel capacity each Ž1 barrel s 42 US gallonss 160 l.x ruptured ŽJ. Kelsey, personal communication, 1995. spilling at most about 3 = 10 4 barrels of fuel oil, about 12% of the amount released during the Exxon
d 13 C Ž‰.
Description
y25.4 y26.4 y25.9 y24.7
Composite oil sample from well Oil from Sec. 3, T21S, R27E Oil from Sec. 7, T22S, R21E Oil seeping from soil down slope below oil rig
Valdez spill of 1989 Ž2.6 = 10 5 barrels.. The tanks were still leaking four years after the earthquake, but the total amount of fuel oil and asphalt that actually entered the sound as a result of the earthquake will never be known because complete records were not kept. The average carbon isotopic composition of the tar mats at the sites of fuel oil and asphalt storage at the old town of Valdez of y23.5 " 0.1 Ž n s 3. is heavier by slightly less than 0.3‰ than the average of 60 Monterey-California-sourced residues of y23.8 " 0.1‰ Ž n s 60; range from y23.5 to y24.1‰.. It is believed that most of the MontereyCalifornia-sourced residues found in Prince William Sound came from fuel oil and asphalt spilled at the old town of Valdez during the 1964 earthquake. The slight difference in carbon isotopic compositions of the postulated source and the resultant residues may be due to more intense weathering of the small Monterey-California-sourced tar balls, dispersed throughout the northern and western parts of the sound, than to weathering of the less vulnerable tar mats on the beach at old Valdez. 4. Summary Oil products used in the developmental history of Alaska, and particularly of the region of Prince William Sound, have a broad range of carbon isotopic compositions, ranging from y22.3 to y29.6‰, with older products Žpre ; 1970. being isotopically heavier and newer products Žafter ; 1970. being isotopically lighter. The reason for the isotopically heavy older products is that they were refined from crude oils with unusually heavy carbon isotopic compositions, generated from source rocks of the Miocene Monterey Formation of California. The
K.A. KÕenÕolden et al.r Chemical Geology 152 (1998) 73–84
82
economic growth of Alaska from the early 1900s to ; 1970 was supported by oil products shipped more cheaply from California than could be produced locally in Alaska. These products were used in various ways such as for fuel, lubrication, construction, and paving. After North Slope crude oil became available in the 1970s, Alaska had more than enough oil to satisfy its economic needs, and oil products shipped from California became much less important. The carbon isotopic compositions of various oil products reflect this change of source from California to Alaska. In addition, on the shorelines of Prince William Sound oil residues can be found from two distinct sources—one in California and the other in Alaska. Alaska ŽNorth Slope crude oil. and the Exxon Valdez oil spill of 1989 are the main source and cause, respectively, of the Exxon Valdez residues. On the other hand, California is the source of the Monterey-California-sourced crude oil, and the Great Alaska Earthquake of 1964 caused its dispersal leading to the Monterey-California-sourced residues. Carbon isotopic comparisons outlined in this paper
suggest that many of the Monterey-Californiasourced residues Žflattened tar balls. came from fuel oil and asphalt, stored in tanks in old town Valdez that were ruptured during the 1964 earthquake, spilling these oil products into the waters of Prince William Sound. Acknowledgements We are grateful to the following people who willingly shared their recollections about oil product usages and occurrence in Alaska: Nancy Lethcoe, Jim Lethcoe, Bill Wyatt, James Williams, Del Webb, Bob Felland, and John Kelsey of Valdez; Linda Hyce and John Labowe of Whittier; Janice Reeve Ogle, Brad Phillips, and L.J. Evans of Anchorage, Larry Evanoff of Chenega Bay; Bill Stokes of Bethel, and Ted Bence of Houston, Texas. Transportation to the sampling sites was accomplished by small boats from NOAA ships MacArthur and Rainier, Alaska Wilderness Sailing Safaris Arctic Tern II, and the USGS RrV Karluk, and by ERA helicopter. Tom Lorenson helped in the preparation of the graphics.
Appendix A. Compilation of carbon isotopic compositions ( d 13 C‰ ) of oil-like residues in Prince William Sound, Alaska— Exxon Valdez residues, Monterey-California-sourced residues, and Exeptions
Sample no.
Location
Latitude ŽN .
Exxon Valdez residues 90-6 Elrington I. 90-18 Knight I. 90-19 Smith I. 90-29 Eleanor I. 90-41 Naked I. 92-22 Knight I.
59858.2 X 60827.6 X 60831.7 X 60834.1 X 60839.4 X 60814.2
92-26
Knight I.
60815.7
92-28 93-9B 93-12B 93-13B 93-13C 93 y 14A 93-15B 93-16A 93-16C 93-18B 93-26B 93-30
Evans I. Ingot I. Knight I. Chenega I. Chenega I. Granite Cove Point Nowell Eshamy Bay Eshamy Bay Culross I. Green I. Knight I.
60806.5 X 60831.9 X 60827.5 X 60822.8 X 60822.8 X 60825.1 X 60826.5 X 60827.9 X 60827.9 X 60838.5 X 60817.6 X 60809.8
Longitude ŽW .
X
148810.5 X 147843.4 X 147822.6 X 147834.4 X 147822.9 X 147843.5
X
X
147846.2
X
147857.7 X 147837.7 X 147842.6 X 148800.5 X 148800.5 X 147857.7 X 147856.2 X 147857.6 X 146857.6 X 148807.0 X 147824.5 X 147845.4
X
X
d 13 C Ž‰ .
Description
y29.3 y29.2 y29.4 y29.1 y29.4 y29.5
Oiled sediment, high tide line, inner bay Oily sand, Herring Bay Oiled cobbles, north side of island Solid oil on rock, Northwest Bay Oiled cobbles, McPherson Bay Oily fissile shale, south arm, Snug Harbor Solid oiled mat, North arm, Snug Harbor Solid oiled mat, Shelter Bay Solid oiled mat, archaeological site Solid oiled mat, Herring Bay Sticky tar in cracks of rock, north end Semi-sticky tar on rock Semi-sticky tar on rock and in crack Oily matted organic debris Weathered tar-cemented barnacles Tar matted organic debris Sticky oil among beach cobbles Tar-like residue on rock Oily pebbles, Point Helen
y29.4 y29.3 y29.6 y29.4 y29.8 y29.3 y29.2 y29.4 y29.3 y29.3 y29.3 y29.2 y29.4
K.A. KÕenÕolden et al.r Chemical Geology 152 (1998) 73–84 X
147850.4 X 147850.4 X 147850.4 X 147850.5 X 147853.4
60806.7
X
147853.4
60806.7
X
147853.4
94-2A 94-2B 94-2C 94-2D 94-5A
Latouche I. Latouche I. Latouche I. Latouche I. Evans I.
60803.9 X 60803.9 X 60803.9 X 60803.9 X 60806.7
94-5B
Evans I.
94-5D
Evans I.
X
X
X
147835.0 X 148811.0 X 152821.9 X 152839.0
X
153854.3
X
148810.5 X 147824.7 X 146847.7 X 147819.9 X 147820.7 X 147821.3 X 147846.1 X 147858.0 X 147809.0 X 147834.0 X 147835.5 X 147823.0 X 147826.5 X 146820.1 X 146819.9 X 146826.2 X 146826.0 X 146833.9 X 146838.5 X 146838.5 X 146841.6 X 146841.6 X 147823.9 X 147837.7 X 147837.7 X 147837.7 X 147836.5 X 147842.6 X 148800.5 X 147857.7 X 147857.7 X 147857.7 X 147856.2 X 147856.2 X 147857.6 X 147857.6 X 147856.5 X 148807.0 X 147852.6 X 147844.9 X 147806.8 X 147806.8 X 147808.8 X 147809.0 X 147840.2
94-13 95-13 95-52 95-56
Unakwik Inl. Elrington I. Shuyak I. Shuyak I.
60852.8 X 59858.5 X 58838.0 X 58833.9
95-58
Kodiak I.
57842.4
Monterey-California-sourced residues 90-6A Elrington I. 90-37A Storey I. 92-5 Valdez Arm 92-16 Naked I. 92-18C Naked I. 92-20 Green I. 92-25 Knight I. 92-29 Evans I. 92-35 Glacier I. 92-36B Olsen I. 92-37 Olsen Cove 92-38 Naked I. 92-39 Naked I. 92-40 Valdez Harb. 92-41 Valdez Harb. 93-1 Port Valdez 93-3 Port Valdez 93-4 Port Valdez 93-5 Valdez Narr. 93-6 Valdez Narr. 93-7A Valdez Arm 93-7B Valdez Arm 93-8 Peak I. 93-9A Ingot I. 93-10A Ingot I. 93-10B Ingot I. 93-11 Block I. 93-12A Knight I. 93-13A Chenega I. 93-14B Granite Cove 93-14C Granite Cove 93-14E Granite Cove 93-15A Point Nowell 93-15D Point Nowell 93-16B Eshamy Bay 93-16D Eshamy Bay 93-17A Crafton I. 93-18A Culross I. 93-20 Perry I. 93-21 Lone I. 93-22A Growler I. 93-22B Growler I. 93-23A Glacier I. 93-23B Glacier I. 93-24 Disk I.
X
59858.2 X 60843.9 X 61800.0 X 60840.3 X 60840.6 X 60818.2 X 60815.8 X 60806.5 X 60854.0 X 60852.2 X 60852.1 X 60839.0 X 60842.0 X 61807.6 X 61807.7 X 61805.3 X 61805.2 X 61804.7 X 61804.3 X 61804.3 X 60859.5 X 60859.5 X 60842.3 X 60831.9 X 60832.0 X 60832.0 X 60831.9 X 60827.5 X 60822.8 X 60825.1 X 60825.1 X 60825.1 X 60826.5 X 59826.5 X 60827.9 X 60827.9 X 60830.5 X 60838.5 X 60842.8 X 60841.8 X 60854.1 X 60854.1 X 60854.3 X 60854.0 X 60829.3
X
X
X
y29.3
Live oil on pebbles, Sleepy Bay Oil patina on cobble, Sleepy Bay Oil mat-like pavement, Sleepy Bay Oil cemented pebbles, Sleepy Bay Sticky oil on pebbles, near Bishop Rock Oil in pocket of rock, near Bishop Rock Tar with needles on rock, near Bishop Rock Sticky tar patch, Mueller Cove Tar cemented sand Oily pebbles from beach, Point Banks Oily pebbles from beach, west side of island Oily pebbles from beach, Chief Point
y23.8 y23.9 y23.7 y23.7 y23.8 y23.8 y23.8 y23.7 y23.8 y23.8 y23.8 y23.9 y23.9 y24.0 y23.6 y23.6 y23.7 y23.7 y23.7 y23.7 y23.8 y23.7 y23.8 y24.0 y23.7 y23.8 y23.7 y23.9 y24.3 y23.7 y23.7 y23.5 y23.8 y23.7 y23.6 y23.7 y23.7 y23.8 y23.8 y23.7 y23.7 y23.7 y23.6 y23.7 y23.7
Tar on rock, inner bay Tar on cobble, north side of island Tar on rock, east side of Valdez Arm Tar on rocks, McPherson Bay Tar on rocks, point east of McPherson Bay Tar on rock, northeast end of island Tar on rock, North arm, Snug Harbor Tar on rock, Shelter Bay Tar on rock, Eagle Bay Tar on rock, Exxon Site 6 Tar on rock, Exxon Site 7 Tar on metashale, Bass Harbor Matted tar on northern point of island Tar on rock, Outer Point Tar on rock, Dock Point Tar mat at Salmon Creek Tar mat near Salmon Creek Tar on rocks, Anderson Bay Tar on rock, east side Tar mat cementing rock, east side Tar on rock, east side Sticky tar mat, east side Soft tar on rock, north shore Tar on rock, archaeological site Soft tar on beach, north side Hard tar on beach, north side Sticky tar on cobble beach Tar on rocks, Herring Bay Sticky tar on rock Tar on rock, north end Sticky tar on rock, north end Lusterous tar on rock, north end Sticky tar on rock Tar on rock Sticky tar on beach, south entrance Soft tar on beach, south entrance Tar on rock, west side of north point Sticky tar on rocks, southeast side Tar on rocks, east side Sticky tar on rocks, north shore Tar on cobbles Tar cemented conglomerate Tar on rock, Elder Bay Tar on rock, Eagle Bay Žsame as 92-35 . Tar on rock
y29.5 y29.3 y29.4 y29.4 y29.4 y29.5 y29.3 y29.4 y29.1 y29.3 y29.3
83
K.A. KÕenÕolden et al.r Chemical Geology 152 (1998) 73–84
84 Sample no.
Location
Latitude ŽN .
93-25 93-26A 94-2E 94-2F 94-5C 94-6A 94-6B
Ingot I. Green I. Latouche I. Latouche I Evans I. Squire I. Squire I.
60830 X 60817.6 X 60804.0 X 60804.0 X 60806.7 X 60814.9 X 60814.9
147838 X 147825.8 X 147850.5 X 147850.5 X 147853.4 X 147856.8 X 147856.8
94-6C 94-7 94-8 94-10
Squire I. Valdez Arm. Perry I. W. Eickel. B.
60814.9 X 61802.5 X 60843.5 X 60853.9
X
147856.8 X 146847.4 X 147858.0 X 147819.6
94-11 94-12 94-14 94-15 94-18A
Glacier I. N., Flent Pt. Naked I. N., Elf Pt. Buyers Cove
60852.9 X 60856.6 X 60839.3 X 60856.8 X 60855.2
X
147818.1 X 147808.2 X 147826.4 X 147803.0 X 147816.7
95-8A 95-14 95-15 95-29
Ellamar Ingot I. Eleanor I. Perry I.
60853.7 X 60830.0 X 60833.8 X 60841.1
X
146842.1 X 147838.7 X 147834.5 X 147855.2
Exceptions 92-19 93-19
Green I. Culross I.
60818.2 X 60844.9
X
147821.3 X 148810.7
X
Longitude ŽW . X
X
X
X
X
References Hostettler, F.D., Kvenvolden, K.A., 1994. Geochemical changes in crude oil spilled from the Exxon Valdez supertanker into Prince William Sound, Alaska. Organic Geochemistry 21, 927–936. Kvenvolden, K.A., Hostettler, F.D., Rapp, J.B., Carlson, P.R., 1993a. Hydrocarbons in oil residues on beaches of islands of Prince William Sound. Marine Pollution Bulletin 26, 24–29. Kvenvolden, K.A., Carlson, P.R., Threlkeld, C.N., Warden, A., 1993b. Possible connection between two Alaskan catastrophes occurring 25 yr apart Ž1964 and 1989.. Geology 21, 813–816. Kvenvolden, K.A., Hostettler, F.D., Carlson, P.R., Rapp, J.B., Threlkeld, C.N., Warden, A., 1995. Ubiquitous tar balls with a California-source signature on the shorelines of Prince William Sound, Alaska. Environmental Science and Technology 29, 2684–2694. Lethcoe, J., Lethcoe, N., 1994. A History of Prince William Sound, Alaska. Prince William Sound Books, Valdez, AK.
d 13 C Ž‰ .
Description
y23.7 y23.9 y23.8 y24.1 y23.8 y23.7 y23.7
y22.4 y23.6 y24.1 y22.3
Tar on rock, southwest side Tar on rock, north shore Tar on log at storm berm, Sleepy Bay Tar on rock, Sleepy Bay Tar on rock, near Bishop Rock Tar with old needles on rock, west side Tar with new needles on rock, west side Tar on rocks, west side Tar on rock, Sawmill Bay Scatter tar on boulders, West Twin Bay Tar on rock, mainland side, Glacier Passage Tar on rock, Irish Cove Tar on wood at high tide, W. Columbia Bay Tar on rock, Cabin Bay Tar on large rock, near Columbia Bay Tar on rock, mainland side, Glacier Passage Tar cobble on beach Tar cemented cobbles Tar on rock Tar on rock at wharf site
y26.6 y27.8
Oil on rock, northeast end of island Sticky oil on rock, Culross Bay
y23.7 y23.7 y23.8 y23.7 y23.7 y23.7 y23.6 y22.8 y23.7
Page, D.S., Boehm, P.D., Douglas, G.S., Bence, A.E., 1995. Identification of hydrocarbon sources in benthic sediments of Prince William Sound and the Gulf of Alaska following the Exxon Valdez oil spill. In: Wells, P.G., Butler, J.N., Hughes, J.S. ŽEds.., Exxon Valdez Oil Spill: Fate and Effects in Alaska Waters, ASTM STP 1219, American Society for testing and Materials, Philadelphia, pp. 41–83. Standard Oil of California, 1979. 1879–1979, One Hundred Years Helping to Create the Future. Standard Oil of California. White, G.T., 1962. Formative Years in the Far West—A History of Standard Oil of California and Predecessors through 1919. Appleton–Century–Crofts, New York. Wilson, B.W., Tørum, A., 1972. Effects of the tsunamis: an engineering study. In: The Great Alaska Earthquake of 1964, Oceanography and Coastal Engineering. National Research Council, National Academy of Sciences, Washington, DC, pp. 361–523.