The oil industry changed that perspective quickly. They brought attention to the hydrocarbon reserves locked in the subsurface stratigraphic traps that underlie the surface topography. Even so, wetland exploration required rethinking exploration techniques. Boats and barges were essential. Oilmen needed port facilities to support their marine operations. None existed. It was not until the 1930s that the necessary support facilities were developed sufficiently to make extensive wetland exploration practical. To approach potential drilling sites, suction or bucket dredges cut navigable channels through the region's swamps and marshes. The completed canals guaranteed lease access. A major problem remained. The industry needed a mobile drilling system that provided maximum drilling capabilities with minimum tear-down and set-up time. A shallow-draft, floating, drilling platform was required.
By 1933, the Texas Company had obtained the rights to such a platform and began a new era in petroleum exploration in wetland environments. In that same year the first attempt was made to drill a well in the Gulf of Mexico. It was not until 1947 that an oil consortium successfully completed a well out-of-sight of land. This well opened a new chapter in the petroleum industry and completed the land, marsh/swamp, and offshore exploration history of Louisiana's petroleum industry.
Although production numbers declined in the 1980s and early 1990s, the use of new technologies on and offshore suggest Louisiana may be poised for another boom. This hydrocarbon province is hardly dead; it is alive and well. The lure of large finds in deepwater off Louisiana's coast, coupled with new incentives, helped generate a record number of bids at the April 1996 federal auction of Gulf leases. The sale resulted in $520.9 million in bids (Griggs, 1996A) and represented the first sale involving deepwater tracts eligible for consideration under the Deepwater Royalty Relief Act. After completion of a two-phase evaluation process, $511 million was added to the Federal treasury.
Beginning with 'Cognac' and 'Bullwinkle' the industry has focused with considerable success on deepwater. To meet this deepwater technological challenge, Auger, Tahoe, Mars and Ursa platforms have been installed or planned. In 1994 Auger was established in more than 2,800 feet of water'an event that captured the public's attention. Several of the platform's nine wells produced oil in volumes greater than ever before in the Gulf of Mexico, as much as 55,000 barrels per day. The Mars field commenced in July 1996. By August, production from this field reached 100,000 barrels of oil a day'clearly establishing deepwater as America's new oil and gas frontier.
In less than three years effective operating depths doubled. When Ursa comes on-line, it will operate at more than 4,200 feet'1,000 feet short of a mile and be the largest structure in the Gulf of Mexico. Initial production rates should be up to 30,000 barrels a day. Baldpate, Neptune, Troika, Genesis, Petronius, Allegheny, Fuji and Gemini are just a few of the structures that will be added to the inventory of deepwater production facilities by the year 2000. Several of these structures are being designed to operate in 10,000 feet of water.
Onshore, western and central Louisiana have 'become the hottest drilling sites in the nation' (Griggs, 1996B:1H). In this region there is a double opportunity to find marketable hydrocarbons either in the Tuscaloosa Trend or in an overlaying band called the Austin Chalk'a play that has sparked a leasing frenzy across Louisiana. Using three-dimensional seismic geology (that photographs the earth's crust with sound waves) and improvements in drilling technology (including advanced horizontal drilling techniques that allows a drill bit to penetrate geological formations in one or more directions) increases the chances of finding oil and/or natural gas. These innovations, coupled with new state incentives, have lowered the costs to find hydrocarbon reserves and improved the probability of discovering these reserves. There is, therefore, renewed interest in Louisiana prospects. In this regard, oil companies are investing millions in leasing and exploration programs. These companies are quite confident in their ability to find marketable hydrocarbons, since a 100% success rate has been realized in some company's programs of re-entering old fields to squeeze out more production. The state is undergoing a mini oil boom. With little to no fanfare, indeed in relative anonymity, the industry has been reborn. With this renewed activity, the chance of an accidental discharge of oil is increased'particularly vulnerable is the state's valuable estuarine/ marine environments. Louisiana's on and offshore production, coupled with the quantity of oil transported through the states ports, waterways and pipelines, also contribute to the danger.
Unlike the 'gushers' that characterized the industry's early history, wild wells are rare today. The most frequent spill is small and measured in tens of barrels, not thousands; nevertheless, they are important. Reactions to an oil spill range from major international media events to development of regional contingency plans. The later guides the response community through the spill event and the habitats that may be impacted by the spill. The basis of any good plan is a map that aids the response community in maximizing their efforts by minimizing their logistic support problems. This may, in fact, be the overriding theme of any disaster.
STATE-OF-THE ART TECHNOLOGY AND MAPS IMPROVE RESPONSE AND CLEAN-UP PROCEDURES
Immediately after the 1989 Exxon Valdez incident, Federal legislation in the form of the Oil Pollution Act of 1990 was passed that established a multiple-oil-spill-cleanup consortium and clarified lines of responsibility in case of future oil spills. This Act became the industry's guidelines. Heightened awareness of the vulnerability to similar incidents in several coastal states, led Alaska, California, Texas, and Louisiana lawmakers to enact complementary legislation to the federal law. In 1991 the Oil Spill, Prevention and Response Act was passed in Louisiana. However, before Louisiana's Oil Spill Coordinator could develop a contingency plan as outlined in the Act, a fully delineated inland boundary map for coastal waters was required .
Left photograph is a Landsat TM satellite image of Louisiana from the CD. The middle photograph displays Louisiana with an overlay of parish boundaries and USGS 1:24K quads. The photograph on the right shows Louisiana with an overlay of primary and secondary roads and the 1:100K grid with one quad filled with tertiary roads.
This map is outlined and discussed in the Act, with 'coastal waters' being defined as ... 'the waters and bed of the Gulf of Mexico within the jurisdiction of the State of Louisiana, including the arms of the Gulf of Mexico subject to tidal influence, estuaries, and any other waters within the state if such other waters are navigated by vessels with a capacity to carry ten thousand gallons [ca. 240 barrels] or more of oil as fuel or cargo.' In addition, the Act requires that 'prior to adopting the state oil spill contingency plan, the coordinator shall, by rule, adopt a fully delineated inland boundary for coastal waters ... The boundary, as adopted, shall be clearly marked on large scale maps or charts, official copies of which shall be available for public inspection...'
Why a map of coastal waters?
These statutorily-derived instructions, in some cases were considered vague, because of difficulties identifying and defining the arms of the Gulf of Mexico subject to tidal influences and estuaries. Even though the language was a problem, it was mitigated by using as the map's northern wetland boundary watercourses that are navigated by vessels with a capacity to carry 10,000 gallons or more of oil as fuel or cargo. The focus was on those waterways the U.S. Army Corps of Engineers (New Orleans District) recognizes as navigable. Although the language in the Act focused on an 'inland boundary for coastal waters,' north Louisiana's navigable waterways were not ignored. For consistency purposes, these water bodies were considered and incorporated in the contingency plan map when appropriate to do so. The completed map serves as a visual indicator of the water bodies navigated by vessels transporting 10,000 gallons or more of oil as fuel or cargo. This element assists oil spill response planners and state and federal regulators to base their response guidelines on actual data rather than theoretical premises concerning waterborne oil shipments. Since every parish (county) in Louisiana produces hydrocarbons, the map is a significant response tool throughout the state, but it is particularly important in the Louisiana's swamp and marsh environments.
|(Top): Zoom of Morgan City area with |
primary, secondary, and tertiary roads.
Area shows city, Atchafalaya River,
Lake Palourde and the intra coastal
waterway. The area is a critical junction
and surrounded by various waterways
and water bodies in a very sensitive area.
(Bottom): The Morgan City area with
Click on this photo for close-up view.
Since Louisiana contains about 40% of the country's wetlands, and the region has been an active hydrocarbon province for more than 90 years, it is an environment at risk of a 'blowout,' pipeline rupture, barge or ship collision, or oil spilled during transfer from one carrier to another. In addition, it is the site of land loss rates that exceed 25 square miles per year. Therefore, the land-water interface is constantly changing, with even the best available U.S. Geological Survey (USGS) printed maps being obsolete on the day they are printed. This is a serious dilemma. The solution was development of a 30-meter-seamless-satellite image of Louisiana, working through a geographic information system (GIS ) engine to provide the response community with a simple and easy tool to help meet their mapping needs. To improve distribution the map is available as a hard copy, on a CD ROM with appropriate GIS overlays, and on the internet at http://atlas.lsu.edu.
ON AND OFFSHORE OIL SPILLS
The northern Gulf of Mexico is one of the most developed and impacted areas in the world with regard to offshore oil and gas activities. The vulnerability of Louisiana's coast from an oil spill derived from the Outer Continental Shelf (OCS) is, therefore, of great concern. Of the more than 3800 active production platforms located on the country's OCS, less than 30 are not in the Gulf of Mexico (Fran'ois, 1993; U.S. Department of the Interior, ... 1994). The vast majority of these structures are located off Louisiana's coast. Spill potential is great, but the actual quantity of oil spilled from these operations is relatively small. Between 1971 and 1991 oil production from OCS wells was over 7.1 billion barrels. During this 20-year period oil spills accounted for 108,000 barrels. This represents .0015% of what was produced'roughly equivalent to spilling one forth of a teaspoon of gasoline from a 20-gallon fuel tank (U.S. Department of Energy, 1994). Spilled oil from offshore activity is relatively small (Gallaway, 1981). In comparison, Bedinger et al (1980) estimated the Mississippi River may add more than 151,000 barrels of oil to the Gulf annually. Any spill is a concern, regardless of the source, and Louisiana's shoreline is the first line of defense against these events. With a coast that is constantly changing, up-to-date maps are critical in the spill-response-planning process.
In 1994 a total of 3,471 oil spills affecting state waters and/or state lands were reported to the Louisiana Oil Spill Coordinator's Office. To assist the state's natural resource trustees oversee development and utilization of practical oil-spill countermeasures, the Oil Spill Coordinator's Office announced in September 1995 the state's oil spill Contingency Plan was available for distribution. The Plan defines how Louisiana will respond to actual or threatened discharges of oil and direct clean up from such releases. The Plan could not be fully implemented until the Oil Spill Contingency Plan Map was completed (Louisiana Oil Spill ..., 1995).
LOUISIANA OIL SPILL CONTINGENCY PLAN MAP
The Oil Spill Contingency Plan Map is designed to provide a document for oil spill planning and response. The map was developed using Landsat Thematic Mapper (TM) satellite imagery of the entire state to provide an up-to-date view of environmental and land-cover conditions. Louisiana has experienced significant land change in the past 30 years, making most available maps obsolete, especially those of coastal areas where maximum land loss is currently estimated at more than 25 square miles per year. The Contingency Plan Map delineates an inland boundary for coastal waters based on the location of estuaries and the maximum extent of astronomical high tide. It also depicts waterways navigated by vessels carrying 10,000 gallons of oil as fuel or cargo. The final product is a multi-color image of Louisiana on a CD that is digitally maintained in a GIS at the resolution of the source data (30 meters) accessible through ArcView'.
The design team has incorporated the following spatial data on the CD.
- Landsat Thematic Mapper (TM) composite satellite image;
- U.S. Geological Survey Digital Line Graph road network;
- Parish political boundaries;
- U.S. Geological Survey 1:100,000 quadrangle index;
- U.S. Geological Survey 1:24,000 quadrangle index;
- Water related place names;
- Populated place names;
- Latitude/longitude graticule; and
- Astronomical high tide line.
Key features include:
- the ability to display the TM image and zoom into any specific area of interest;
- the ability to identify geographic coordinates of a feature and/or its location;
- measure length, radius and/or area of features;
- zoom to features or themes outlined in the table of contents;
- select geographic themes for display;
- identify features such as highway numbers;
- locate features such as specific highways;
- select features based on data base attributes;
- select features within polygon, box or proximity radius;
- query theme database using logical expressions;
- capture information for hard copy plotting or to export to graphic program;
- display information from database for feature such as population of town;
- use satellite image backdrop for context of spatial features; and
- determine parish or quadrangle name of any specific site.
There are numerous creative uses for this CD and the application depends on the individual, or collective imagination of the user community. It is a tool that should be used, and to our knowledge the CD represents a first, not only for Louisiana, but the nation as well.
The impact of an oil spill and the success of cleanup efforts depend on the characteristics of the water and land nearby and weather conditions. In some cases, luck'good and bad'plays the prominent role in determining the severity of a spill. The shallower the water, the greater the damage likely to occur to life on the bottom. High winds and ocean currents can spread oil faster and impede cleanup efforts. Tidal mud flats, swamps, marshes and shallow grass beds are especially difficult to clean. The time of day a spill occurs also can be important, as initial response can only benefit from adequate sunlight and good visibility. The key to an effective response plan is that 'the level of pre-existing environmental and ecological information is extensive, current and easily extracted from a comprehensive data base' (Ritchie, 1995:76). One of the best tools in understanding the pre-existing environmental conditions is a interactive digital map. Louisiana's Oil Spill Contingency Plan Map is a key element in mobilizing clean-up teams to minimize the environmental consequences associated with an oil spill.
Bedinger, C.A., J.W. Cooper, A. Kwok, R.E. Childers and K.T. Kimball. 1980. Ecological investigations of petroleum production platforms in the central Gulf of Mexico. Volume 1: Pollutant fate and effects studies. Draft final report submitted to the Bureau of Land Management. Contract AA551-CT8-17. 149 pp.
Fran'ois D.K. 1993. Federal offshore statistics: 1992. U.S. Department of the Interior, Minerals Management Service. OCS Report MMS 93-0066: U.S. Government Printing Office, Washington, D.C., 155 pp.
Gallaway, B.J. 1981. An ecosystem analysis of oil and gas development on the Texas-Louisiana continental shelf. U.S. Fish and Wildlife Service, Office of Biological Services, Washington, D.C. FWS/)BS-81/27. 89 pp.
Griggs, T. 1996A. Incentives drive bides for offshore leases in Gulf to record number. Baton Rouge Sunday Advocate, April 28, 1996, pp. 1 H.
Griggs, T. 1996B, Louisiana now the place to drill as companies tap the Austin Chalk. Baton Rouge Sunday Advocate, April 28, 1996, pp. 1 H.
Louisiana Oil Spill Coordinator's Office. 1995. Louisiana oil spill prevention and response act: Oil Spill Coordinator's Office, Office of the Governor, Baton Rouge, Louisiana, 19 pp and appendices.
Ritchie, W. 1995. Maritime oil spills - Environmental lessons and experiences with special reference to low-risk coastlines. Journal of Coastal Conservation, v. 1, p. 63-76.U.S. Department of Energy. 1994. The oil pollution act of 1990: issues and solutions - a report of the National Petroleum Council, July 1994: The National Petroleum Council, Washington, D.C., 89 pp and appendices.
U.S. Department of the Interior, Minerals Management Service. 1994. Current facts and figures, Minerals Management Service, offshore oil and gas operations, Gulf of Mexico OCS region: U.S. Department of the Interior, Minerals Management Service, Gulf of Mexico OCS Regional Office, New Orleans, Louisiana, 2 pp.
The source of the original satellite imagery was obtained from the USGS National Wetlands Research Center, Baton Rouge, LA Project Office. The imagery was processed, mosaiced and converted to 8-bit format in the LSU Department of Geography and Anthropology.
Donald W. Davis is the Administrator for the Louisiana Applied and Educational Oil Spill Research and Development Program; Karen Reeder is the Assistant Administrator; DeWitt Braus is the GIS Manager for the Department of Geography and Anthropology at Louisiana State University and Roland Guidry is the Louisiana Oil Spill Coordinator.