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where the objectives of academia, industry and government are intertwined in a complex and still not fully agreed upon program.
Question 1. Assuming this program means six to ten holes drilled, what important scientific questions can be addressed with these holes and how fully will the questions be resolved by the data gathered ?
Personally I am a strong supporter of an expanded program of continental shelf studies. More than 50 percent of the continents are covered by over 2km of sediment and much of it is there as a result of processes analogous to those creating the present passive margins. Thus studying these margins is important not only in their own right but also because these studies may well shed light on the processes creating the large accumulations of sediment now found on the continents. I believe that we have a good conceptual model as to how these margins were formed and can test this model quantitatively. I feel that studying the continental margins is a first order problem which can be resolved at this time using small modifications of conventional techniques.
The most important scientific objectives to be tackled by studying the continental margins have been addressed in the National Research Council report, Continental Margins-Geological and Geophysical Research Needs and Problems. With some minor modifications I support the conclusions of this report. The most important scientific objectives are: (1) What is the relation of the margins to the continents on one side and the oceans on the other? (2) How were the margins created-by extension, by thermal cooling or by some combination of both? (3) What kind of sediment has been deposited in the margin, how did it get there and what has happened to it since it was deposited ? (4) What do the oldest sediments tell us about the early history of the Atlantic Ocean?
As I understand it the margin drilling in the present program consists of three or four holes off the east coast of the U.S. and one hole in the Gulf of Mexico. This latter hole is not strictly marginal drilling but I have included it with this group because it has many of the same objectives as the margin holes. These holes are to be drilled at a water depth of 2000 to 4000 m. Strictly speaking this program is not ocean margin drilling but continental slope drilling.
I have difficulty supporting this continental slope drilling program because few of the basic questions I have outlined can be resolved by the drilling as it is presently planned. Though the program is in the process of modification it has been tentatively suggested that two sites be located on the IPOD/USGS seismic line off Cape Hatteras. (Figure 1) I will use this seismic section to illustrate my problems with this program.
The holes are to be drilled in water depths of between 2 and 4km. At this water depth the sediments are very thick and even 6km of sediment penetration (which I consider unlikely and very time consuming) will not reach the oldest sediment above oceanic basement. (See figure 1) Thus the oldest sediments cannots be reached by drilling in this area and examining the earliest history of Atlantic opening (first 5 to 10 million years) is beyond the scope of this project. It is possibe that there are other areas on the east coast of the U.S. where such old sediments are within drilling range. If so, much more geophysical work is needed to locate where such sediments might be found.
The holes will not reach and hence not sample basement. Further because we do not know precisely the water depth at the time of deposition we cannot determine the past thermal history of the slope as a function of time. As a consenquence these holes will add nothing to the questions of whether the basement is continental or oceanic or to how the margins were formed in the first place. Holes on the shelf where the water depth is known at the time of deposition (they were deposited at sea level) at least give information about the thermal history. If the marginal holes are to drill basement more geophysical surveys are needed to locate such areas where basement can be reached.
FIGURE 1.--The hatched area gives the deepest sediment to be reached by OMD
program. Note that the deepest sediment between 50 and 150 km off the coast cannot be reached. This represents earliest 5 to 10 million years history.
What the drilling will answer is the third objective; i.e. what sediment is to be found beneath the slope and how it has changed through time. Further the local geophysical surveys done before the drilling will go a long way to resolving the question of how sedmiment got to where it was deposited. As an academic geophysicist I do not find a program involving one year of drilling to find out the structure of the proposed carbonate bank, the diapir complex or the sediments on either side very appealing. Yet I know there are some in our community who would disagree with me and say that though these structures or the sediments are a local problem the results here can be generalized to other oceans. This is a valid point and as I am not a sedimentologist I cannot argue with this position. On the other hand, I am dubious as to whether answering only one out of the four major scientific objectives is of sufficient importance as to justify the drilling of four very expensive holes.
However, as I mentioned in my testimony, there is another way of looking at this problem. My group has done a preliminary analysis of this seismic section. (See figure 1) We think that conditions are such that should adequate source material have been deposited in the Jurassic (i.e., just beside the diapir complex) then the temperature depth history of these sediments is such that there might be significant accumulations of oil and gas either near the carbonate bank or the diapir complex. The possibility of these accumulations rests on the question of whether or not there was adequate source material, whether there is a reservoir and if the reservoir has been sealed. I think the oil industry is willing to support the drilling on the slope to answer the above questions. To an oil company scientist such a problem is first order and hence very important. Also the drilling will answer the questions.
Question 2. What important research that might be done on the continental shelf will not be included in the proposed program and how much would such research cost?
As a geophysicist I am most interested in finding out the structure of the continental margins and how these margins were formed. To answer these questions I would like
(a) To have access to drill hole data in shallow water because this gives the thermal history of the shelf.
(b) To be able to run deep focusing multichannel seismic reflection traverses across the margin to examine the sedimentary structure just above basement, and
(c) To have seismic refraction traverses run over the seismic reflection lines to look in detail at the crust as it changes from continental to oceanic.
Simple theories predict that all of these observations are related and that from one the others can be predicted. Further we believe that we can estimate the degree of maturity of hydrocarbons beneath the shelf if adequate source material has been deposited. We wish to compare these predictions with observations.
At present, deep multichannel seismic reflection data and the deep refraction information across most continental margins are inadequate for this purpose. For example, there is no deep refraction data from beneath the COST B-2 well in the Baltimore Canyon Trough area. The absence of this data prevents us from developing a good quantitative thermal model for this area of active oil exploration.
The Ocean Margins Drilling program recognized this deficiency and, I believe, $70 million over 10 years has been allocated for geophysical research. Though such a sum will cover the work around the four slope holes it is not sufficient for the broad based geophysical program that I believe is necessary to get the best results from a scientific drilling program.
The Continental Margins report estimated that geophysical traverses run by two ships across the margins would cost (including ship time) $18 to 22 million per year. To obtain a feeling of scale, the oil industry spends about $3 billion per year on offshore survey work. Personally though I believe a two ship program would be better. The academic community geophysical program could be trimmed to one ship costing $9 to 11 million per year. Allowing for inflation this produces a figure of about $150 million over ten years.
I support the Continental margins report which states (page 13) "We fully and emphatically concur with the recommendations of the JOIDES subcommittee on the Future of Scientific Ocean Drilling (FUSOD) that an ambitious drilling program be undertaken, but only if adequate funding is assured for scientific studies (italic from report) that include (1) broad scale problem definition, (2) small-scale site examination and preparation, (3) sample analysis and well-logging and (4) interpretation and synthesis.
In the present Ocean Margins Drilling program I see two problems. There is not adequate funding to cover the broad based problem definition and a limitation is placed on the scientific objectives by the necessity of drilling in water depths between 2000 and 4000 meters.
However, there is a simple solution which would answer my objections. Drop the hold in the Gulf of Mexico and put the money saved into the geophysics program. This would save $70 million in drilling costs which added to the present geophysics budget would give $140 million or enough for part of the geophysical program outlined in the Continental Margins report. This would also provide enough money for much of the survey work to be carried out prior to drilling. Further one of the three deep holes on the slope could be moved into much shallower water (less than 1000 meters depth). For the price of one deep hole one could get two or three shallow holes. These could be used to make a transect of wells over the most useful geophysical traverse.
If this were done I would feel much happier about the scientific merits of the program. I am not against ocean margin drilling as such but rather I think the program needs to be refocused to answer specific scientific problems. However, the solution of these problems by drilling should not be undertaken until adequate background geophysical data is available and some consideration is given to drilling in water shallower than 2000 meters. Both the broad based geophysical program and the lifting of the restrictions on the depth of drilling would benefit the interests of oil company scientists. For instance, more geophysical data in deep water would improve their ability to select the best areas for drilling. This and the removal of the restriction on depth might well result in the picking of single sites which might answer both industrial and academic objectives.
Question 3. If funding were available, how long would it be desirable to continue the Challenger program and what should the program include?
Recently the Challenger program has had two major successes. First, the engineers have made a significant advance in sampling techniques with the hydraulic piston core. This allows, for the first time, the return of completely continuous samples from the soft uppermost sediments of the sea floor. It will permit scientists to extend their detailed studies of sedimentation from the present back to 5 to 10 million years before present. This information will yield more knowledge about sedimentary processes in the deep sea and ultimately may lead to a better understanding of the cause of long term climate changes such as the ice ages.
Second, in the young ocean floor near the Galapagos Islands the Challenger has obtained the deepest penetration of the oceanic crust on the International Phase of Ocean Drilling (IPOD) phase of the program. This hole, which is still open and can be reentered, has penetrated over 500 meters of the hard basalt beneath the sediments. Deep crustal penetration was one of the principle objectives of the IPOD phase.
Personally I think that there is enough good science for the Challenger program to continue for at least another two years. I think this program should include drilling in high and low latitudes with the hydraulic piston core, the continuation of the deep hole near the Galapagos and drilling in the deep waters around Antarctica.
I am not an expert on the fisrt two areas of research mentioned above and further I do not know of the present condition of the Challenger. If you wish more precise information on what such a drilling program should include and how it should be carried out I suggest you ask the planning committee of the JOIDES program which runs the Challenger.
Question 4. Are there significant differences in the scientific results likely from drilling "on structure" to drilling "off structure"'?
Oil and gas normally accumulate "on structure". Drill holes for scientific purposes are located “off structure” to avoid drilling problems associated with these hydrocarbons and to obtain a deeper and more complete sedimentary record.
If the scientific objective is the complete sedimentary record then it is better to drill "off structure". If the objective is the sediment or rock beneath the structure then it is better, because the hole is shallower, to drill "on structure".
As the objective of the OMD program is a complete sedimentary record I see no major reduction in the scientific objectives resulting from the requirement to drill “off structure”.
Mr. Brown. Thank you very much, Mr. Sclater.
Now we have Mr. D. K. McIvor, who is the vice president for producing at Exxon Corp.
[The biographical sketch of Mr. McIvor follows:]
DONALD KENNETH MCIVOR
Donald Kenneth McIvor, Vice President Producing, Exxon Corporation, was born in 1928 in Winnipeg, Canada. He was educated in that city receiving an honors bachelor of science degree in geology from the University of Manitoba in 1950. Immediately after graduation he joined Imperial Oil Limited, Exxon's Canadian affiliate, as a geophysical trainee on a seismic crew in northern Alberta.
Mr. McIvor worked in a professional capacity between 1950 and 1958 on exploration ventures for Imperial in Alberta and Saskatchewan. Between 1958 and 1968 he held a variety of positions in Calgary, including assistant to the exploration manager, supervisor of exploration planning and manager of exploration research. During this time he also held brief overseas assignments in Angola and France, and spent a year as an employee of the Jersey Production Research Company in Tulsa, Oklahoma.
Between 1968 and 1970 he was assistant manager and then manager of the Corporate Planning Department at Imperial headquarters in Toronto. He became exploration manager in 1970, senior vice president and director in 1973, and was appointed Executive Vice President in 1975. He was appointed to his current position in mid-1977.
Mr. McIvor is a graduate of Course XXVI 1972–1973 of the National Defence College, an intensive one-year exposure to economic, political and social issues in both Canada and the rest of the world, attended by senior military, government and industry personnel. He is a member of the Canadian Society of Petroleum Geologists and was a director of the Canadian Mental Health Association.
STATEMENT BY DONALD K. MCIVOR, VICE PRESIDENT FOR
PRODUCING, EXXON CORP. Mr. McIvor. Thank you, Mr. Chairman.
In the capacity that you just mentioned that I filled at the Exxon Corp., I am responsible for the coordination of Exxon's worldwide oil and gas exploration and development programs.
I am appearing as a member of this panel at the request of the chairman. However, I wish to make it clear that I have not discussed any of the testimony with the other members of the panel and to emphasize that I am appearing solely on behalf of Exxon Corp.
Exxon Corp. has agreed to participate in the feasibility study for the National Science Foundation's proposed ocean margin drillingOMD-program at the request of Dr. Frank Press, Director, Office of Science and Technology Policy. It is our understanding that the feasibility study will cost no more than $20 million, of which 50 percent will be provided by participating private companies. Exxon is willing to contribute its share of that 50 percent.
Exxon's interest in the marine environment is both historical and continuing. In 1979 the corporation spent $2.3 billion in the search for and development of offshore oil and gas. Exxon has been exploring for oil and gas in the marine environment for more than 50 years, and in 1979 we drilled more than 300 offshore wells.
Over the last few years Exxon has drilled wildcat wells in more than 3,000 feet of water offshore Surinam, Canada, and Thailand in the search for new sources of oil production, and we are currently drilling a well in 4,500 feet of water offshore Australia.
With regard to the proposed 10 year $700 million OMD program, Exxon is unable to determine a clear relationship between the presently projected costs of the OMD program and the potential benefits. Therefore, we have committed to join with others in the feasibility study but are unwilling at this time to commit to the full OMD program as currently envisioned. Depending upon the outcome of the feasibility study, we will be glad to reconsider our position.
We are participating in the feasibility study because we support the commonly held view that the ocean margins represent one of the Earth's least scientifically explored frontiers. We are interested in seeing a continuing scientific effort devoted to this little known segment. We believe the feasibility study will better define the preferred approach to the overall investigation. Our support of this study will supplement other contributions we make to worthwhile scientific programs headed by several oceanographic institutions.
Exxon has been closely associated with the Government-sponsored deep sea drilling project-DSDP-since its inception in 1968. Our scientists and engineers have participated not only in the project's onsite drilling, but have also served on various advisory panels and committees of the project, including those of the National Science Foundation, the Joint Oceanographic Institutions for Deep Earth Sampling, and the international phase of ocean drilling. In our view, the DSDP is an important and successful geologic research investigation. Its basic scientific findings have not only enhanced knowledge of the oceans, but have also revolutionized previous concepts regarding Earth history and processes. These fundamental new concepts, while not directly applicable to oil and gas discovery, are useful in the broader interpretation of geologic data.
An extension of the DSDP to the ocean margins may be the logical next step. Earth scientists now have a reasonably good basic understanding of the geologic history and processes of the deep ocean basins and of the continental shelves out to the 6,000-foot water depth. However, they know very little about the fundamental geologic nature of