Petroleum Exploration Activities Research Articles

Remote Identification of Polar Bear Maternal Den Habitat in Northern Alaska

Polar bears ( Ursus maritimus ) give birth in dens of ice and snow to protect their altricial young. During the snow-free season, we visited 25 den sites located previously by radiotelemetry and characterized the den site physiognomy. Seven dens occurred in habitats with minimal relief. Eighteen dens (72%) were in coastal and river banks. These banks were identifiable on aerial photographs. We then searched high-resolution aerial photographs (n=3000) for habitats similar to those of the 18 dens. On aerial photos, we mapped 1782 km of bank habitats suitable for denning. Bank habitats comprised 0.18% of our study area between the Colville River and the Tamayariak River in northern Alaska. The final map, which correctly identified 88% of bank denning habitat in this region, will help minimize the potential for disruptions of maternal dens by winter petroleum exploration activities. Key words: aerial photography, Arctic National Wildlife Refuge, den habitat, maternal den, photo interpretation, National Petroleum Reserve – Alaska, polar bear, Prudhoe Bay, Ursus maritimus

Chevron's Petroleum Exploration Activities and Productivity 1985–1999

Chevron's Petroleum Exploration Activities and Productivity 1985–1999

Shell Petroleum Exploration and Production 1980 to 1997: Reserves Analysis and Key Financial Statistics in Money and in Real Terms

An analysis of Shell's petroleum exploration activities over an eighteen year period is presented Key findings include; - the cost of finding oil decreased by a factor of four over the period 1981 to 1997. - revision to oil reserves have shown no trend - improved recovery estimates of oil reserves have shown no trend - well analysis shows that whilst in 1980 only one exploration well in four was successful, in 1997 more exploration wells were productive than dry. There is now only a few per cent chance that a development well will be dry compared with a 5 to 10 percent chance of a dry development well in the early 1980s. - depreciation depletion and amortisation (DDA) changes on Shell's reserves have increased substantially in money and in real terms over the last eighteen years. DDA changes are now sometimes equal to capex whilst in 1980 they were only 30 per cent of capex. - from 1982 to 1997, capex per b.o.e. reserves has increased by 60 per cent in real terms. - for crude oil and NGLs, Shell has dropped the reserves to production (RIP) ratio from 13 years in the 1980s to 11 years since 1994. - production costs for oil and gas have fallen from $11.0 per b.o.e. in 1981 to $2.9 per b.o.e.£. in 1997. whilst the net proceeds (selling price of crude oil and natural gas) have fallen from $48.6 b.o.e. in 1981 to $17.0 b.o.e. in 1997, net earnings (profits after tax and all expenses) have fallen from $7.1 b.o.e. in 1980 to $3.5 b.o.e. in 1997 both expressed in (1997) real US$ terms.

Large Volumes of Carbon Dioxide in Sedimentary Basins

Carbon dioxide (CO2) is encountered in many sedimentary basins around the world in a variety of geological environments (e.g. Southeast Asia, Italy, Eastern Australia). Data on CO2 occurrences almost invariably come from petroleum exploration activities and are limited by operational and commercial constraints. Where CO2 is abundant it is effectively a natural 'pollutant' which reduces the worth of the hydrocarbon gas present by diluting it and increasing production costs. However large volumes of CO2 are rare with the probability of there being >1% CO2 being less than 1

The Spratly Islands dispute

The Spratly Islands, in the southern reaches of the South China Sea, have become the focus of an unstabilising territorial dispute. Five of the sea's littoral states or political entities lay conflicting claims to all or part of the island group and have set up military outposts in them as prospects of significant hydrocarbon resources in the sea floor mount. After a 1988 armed clash between Vietnamese and Chinese forces, the claimants have sought ways to manage the conflict peacefully through informal workshops and ASEAN resolutions. Meanwhile, troubling military build‐ups by claimant countries continue and petroleum exploration activity has increased, shifting the emphasis of the dispute from island claims to maritime jurisdiction. Island claims must be settled, however, before the Law of the Sea Convention can be brought to bear. The unique complexity of this dispute makes resolution of sovereignty unlikely and points to multilateral co‐operative resource exploitation.

Update on Petroleum Exploration Activities in the Philippines: ABSTRACT

Update on Petroleum Exploration Activities in the Philippines: ABSTRACT

COOPERATIVE INDUSTRY APPROACH TO ENVIRONMENTAL INVESTIGATIONS IN THE TIMOR SEA

For more than 20 years, oil and gas exploration and production activities have been conducted in the Timor Sea region, including the Sahul Shelf. The Shelf is a large, shallow platform off the Northern Australian Coast, considered to be a recently drowned part of the Australian Platform. Seismic surveys have indicated submerged banks on the edge of this Shelf. Until recently, little was known of the physical nature of these banks, or their ecology.Environmental management of petroleum exploration and development activities in the area is required to avoid potentially impacting the surrounding environment. Accurate information on ecological systems is therefore required in order to design detailed Environmental Management Plans which aim to minimise impacts and protect the environment.BHP Petroleum and Woodside Offshore Petroleum, as operators of permits in the area, independently conducted baseline environmental investigations. This information was exchanged, and the cooperative effort between BHPP and Woodside resulted in a significantly improved environmental resource database, which will aid in the planning and implementation of effective environmental management of petroleum operations.The studies included:Accurate bathymetric surveys to determine the geomorphology of the banks.Acquisition of side-scan sonar for interpretation of substrate features and the preparation of preliminary habitat maps.Remotely Operated Vehicle (ROV) surveys to ground truth habitats, and to determine their distribution and species composition.Grab and drop-core sampling to validate ROV film and provide material for chemical and physical analysis.Collecting current data, to aid in the formulation of management strategies for the disposal of drilling discharges and for oil-spill contingency planning.Deep-water benthic trawling to determine the abundance and composition of epi-benthic macrofauna.The main conclusions were that submerged banks are reef-systems that have variable density of coral cover, which are dependant on depth (light intensity), and substrate type. Thirty metres is assumed to be the maximum depth for reef-flat coral growth. The outer rims of the banks support the highest density of coral growth, probably due to the prevailing strong currents which provide greater feeding opportunities and which maintain bare substrate suitable for colonisation. Bank slopes may support a moderate density of coral cover to 60 m. Where conditions are less favourable for coral growth, reef-flats support the macro-algae assemblages dominated by the coralline alga Halimeda, which contributes between 10–60 per cent substrate cover.Deep-water benthic habitats (>300m) support a low-abundance epi-benthic macrofauna.

OIL SPILL CONTINGENCY PLANNING CRITERIA FOR INTERNATIONAL RIVER BASINS

ABSTRACT Many issues must be taken into account during the development and implementation of bilateral oil spill contingency plans for rivers and river basins shared by two or more countries. Such bilateral plans between Ecopetrol Colombia and PDVSA Venezuela respond to the need for well-designed tools for response to spills in international river basins that are near or within areas where petroleum exploration, production, and transportation activities are being carried out. Information collected during the last six years helped in the development of this bilateral oil spill contingency plan.

Comparison Of Three Uncertainty-Analysis Methods To Assess Impacts On Groundwater Of Constituents Leached From Land-Disposed Waste

Assessment of the environmental fate and behavior of constituents that have the potential to leach from waste-disposal pits that are associated with petroleum exploration and production activities is a problem of interest to industry and regulatory agencies. A stochastic modeling approach for the migration of constituents in soil and groundwater was developed to assess the impact on groundwater at receptors that are downgradient from a waste pit. The model evaluates uncertainties in constituent concentrations in groundwater due to uncertainties in waste-composition and hydrogeologic properties of waste sites, and it determines the probability distributions of constituent concentration at receptor points by using Monte Carlo (MC), First-Order (FO), and Point-Estimate (PE) methods. Application of the FO and PE methods to assess probability distributions requires an assumption of the form of the probability density function for concentration at a receptor point. A log-normal distribution is employed here. A comparison of the three uncertainty-analysis methods is performed to evaluate the efficiency and accuracy of the FO and PE methods relative to the MC method. Results suggest that for non-reactive and conservative constituents the level of accuracy provided by FO method is similar to that of the MC method. The computational effort for the FO method is about 1 percent of that for the MC method. For nonconservative constituents, the FO method compared less favorably with the MC results. Thus, the use of the MC method is warranted, for nonconservative constituents or for cases where a higher degree of precision in the probability distribution is needed.

Petroleum geochemistry of the Midyan and Jaizan basins of the Red Sea, Saudi Arabia

During the 1960s, petroleum exploration activities in the offshore Red Sea areas of Saudi Arabia tested gas and condensate reservoired in the Miocene sands immediately below the Mansiyah evaporites in the offshore Midyan basin. Recent onshore exploration activity in the Red Sea has resulted in the discovery of accumulations of oil, gas and condensate in the Lower Miocene Maqna Group in the Midyan and Jaizan basins. As a result of this exploration success, an effort to understand the origin of these hydrocarbons was initiated. The two basins were assessed geochemically by addressing: (1) the potential source rocks; (2) the extent of the hydrocarbon kitchens; and (3) characterization of the hydrocarbons. The potential source rocks for the reservoired hydrocarbons are: (1) the organic-rich, oil-prone shales of the predominantly evaporitic Mansiyah Formation; (2) the variable quality shales and carbonates of the Magna Group; and (3) the moderately organic-rich shales of the Burqan and Tayran Groups. The reservoired hydrocarbons were characterized by carbon isotopes, gas chromatography-mass spectrometry and gas chromatography and compared with the potential source rocks. The results showed an acceptable match to the Maqna and Burqan organic-rich units. Detailed burial history/thermal modelling projects were undertaken to assess the hydrocarbon kitchens of both basins. Results for the Midyan basin indicated that over large areas Tayran and Burqan sediments are oil to gas mature and may be sources for the gas and/or condensate accumulations, whereas the limited area of mature Maqna sediments may be responsible for sourcing the black oil accumulations. In the Jaizan basin, the Maqna and Burqan sediments range from high oil maturity to thermally spent due to high geothermal conditions and excessive burial. The burial of the source rocks increases fairly rapidly from east to west in the Jaizan basin.

Petroleum hydrocarbon pollution of urban topsoil in Ibadan City, Nigeria

The distribution of total petroleum hydrocarbon in topsoils from various parts of Ibadan city, Nigeria, was studied. Samples were selected from around the following zones: a) railway tracks, b) petrol stations, c) refuse dumps, d) residential areas, e) high traffic density areas, f) mechanical workshops, and g) control zones. Contamination of the topsoil with hydrocarbons was significant only around petrol stations and mechanical workshops where the factors of accumulation were 10.1 and 4.72, respectively. The general trend in hydrocarbon levels was petrol station > mechanical workshop > refuse dumps > high traffic areas > rail tracks > control zones residential areas. The results highlight the need to monitor urban environments that are remote from petroleum exploration activities for petroleum hydrocarbon contamination.

Marine environments of Southeast Australia (Gippsland Shelf and Bass Strait) and the impact of offshore petroleum exploration and production activity

Marine environments of the Gippsland Shelf (Gippsland Basin) and Bass Strait (Bass Basin) are described and an exploratory (preliminary) assessment of the potential effects of petroleum exploration and production activity are outlined. Exploration activity has been undertaken in both areas and inferred environmental impacts are typically short term. Production activities are restricted to the Gippsland Basin, have potential for long‐term impact, and are likely to result in trace levels of hydrocarbons being present within 1 km of the point(s) of discharge of drilling waste or wastewater. The inferred impact of produced wastewater, which may contain up to a maximum of 30 ppm of produced hydrocarbons, on waters of the Gippsland Shelf is presently being modeled and quantified. Results indicate that the background level of produced petroleum in waters of the Gippsland Shelf is less than in areas around Sydney and Melbourne affected by urban runoff. Potential strategies for monitoring environmental quality on the Gippsland Shelf include a biologically based “mussel watch” program.

Origin of Subpressure and Hydrocarbon Exploration in Shiwu Fault Depression, Songliao Basin, China: ABSTRACT

In the Shiwu fault depression, evolutionary history of formation pressure can be deduced on the basis of structural evolutionary history. Uplifting and denudation caused high pressure to evolve into low pressure. The main factors controlling the evolutions are (1) generation of fractures and release of high pressure, (2) temperature reduction and water-cooling pressure reduction, (3) desaturation and gas dissociation, and (4) diffusion and dissipation of gas. According to the pressure evolutionary history, the study area has had two pool-forming stages. During uplifting and denudation, fracture generation, and the transformation from high pressure to low pressure, the protogenic high-pressure oil and gas pools were transformed into low-pressure relic pools, and secondary pools with normal pressure formed above them. A predictor equation of the low pressure has been proposed on the basis of the balanced depth in the undercompaction zone, as well as the eroded thickness of the overlying strata. According to this equation, measured pressure data, well logs, and seismic interval velocity data, pressure prediction has been made in the study area by drawing on experience gained at key points. In the light of pressure evolutionary history and pool-forming history, it is regarded that the exploration potential of the low-pressure zonemore » is not as good as that of the hydrostatic-pressure zone. This has been verified by petroleum exploration activities.« less

SUSTAINABLE DEVELOPMENT AND EXPLORATION

The environment, defined broadly to include both reproducible and natural resources, such as petroleum reserves and wildlife parks, supports all economic and other social activity. The notion of sustainable development arises from a concern that future well-being could be eroded by the pursuit of economic goals which degrade and deplete finite resources.While such concerns are not new, the focus of debate has shifted within the past twenty years. Following the first oil price shock in the early 1970s, questions about whether or not it is possible to maintain growth while energy stocks are declining were brought to the fore. In recent years, however, concerns about the possible negative impact of exploration activity and fossil fuel use on the natural environment — also considered a finite resource — have gained prominence.But achieving sustainable resource use involves making trade-offs. For example, open access to a highly prospective site to help meet the energy needs of current and future generations has to be weighed against the site being partially or fully closed to exploration in order to completely preserve the value of the natural environment inherent in the site.To answer questions about environmental tradeoffs requires judgments about the relative social values of alternative uses of the sites in question. Information based on commercial exploration assists in making such judgments. By upgrading knowledge about the economic and social value of a natural resource, the information gained from exploration can help with making judgments about sustaining or conserving the human environment for future generations. Indeed, because the outcome of the exploration process has both social and commercial implications, it is likely that the level of exploration activities chosen for purely commercial reasons may be lower than the level that would be considered optimal if full account were taken of the trade-offs inherent in maintaining or improving the quality of life of future generations.The purpose in this paper is to investigate the role that exploration can play in improving economic and social well-being generally. To do this, petroleum exploration activity is separated into two phases — first, 'low impact' exploration such as the collection of seismic data and, second, drilling. The key contribution of this paper is to highlight conditions under which levels of low impact exploration, as determined by commercial considerations alone, are likely to be less than the socially optimal level.

EXPLORATION, ENVIRONMENT AND COMMUNITY EDUCATION

BHP Petroleum practice is to undertake a comprehensive environmental management program for exploration activities in environmentally sensitive areas. The planning for the exploration program in the Otway and Duntroon Basins is presented as a case study.BHP Petroleum's exploration activities in the Otway Basin, offshore Victoria, have been the subject of community debate as a result of the perceived effects on sensitive environmental values. The environmental management program undertaken for this exploration project included:a community consultation and information program;development of a geographic information system (GIS) recording a range of environmental and logistical (spill response) information;a whale research program; andformulation and implementation of an environmental management plan.This program and the issues it is designed to address has been an education for the Company, the community and government agencies.

Petroleum Exploration and the Atlantic OCS

The largest Atlantic outer continental shelf (OCS) lease sale was the first one, Sale 40 in 1976. Ninety-three Baltimore Canyon Trough petroleum leases were issued, and industry's winning bids total $1.1 billion. The highest bonus bids were for leases overlying the Schlee Dome, then called Great Stone Dome, a large structure with a very large fetch area. By 1981, seven dry wells on the dome moderated this initial flush of optimism. However, subeconomic quantities of gas and light oil were discovered on the nearby Hudson Canyon Block 598-642 structure. Now after 9 lease sales, 410 lease awards, and 46 exploration wells, United States Atlantic petroleum exploration activity is in a hiatus. Fifty-three leases remain active under suspensions of operation. Twenty-one lease blocks, about 50 mi offshore from Cape Hatteras, have been combined as the Manteo Exploration Unit. Mobil and partners submitted an exploration plant for the unit in 1989. The Atlantic OCS has petroleum potential, especially for gas. With only 46 exploration wells, entire basins and plays remain untested. During the present exploration inactivity, some petroleum evaluation of the Atlantic OCS continues by the Minerals Management Service and others. Similarities and differences are being documented between United States basins andmore » the Canadian Scotian Basin, which contains oil and gas in commercial quantities. Other initiatives include geochemical, thermal history, seismic stratigraphic, and petroleum system modeling studies. The gas-prone Atlantic OCS eventually may make an energy contribution, especially to nearby East Coast markets.« less

Noise and Vibration Levels in Artificial Polar Bear Dens as Related to Selected Petroleum Exploration and Developmental Activities

The noise and vibration levels resulting from seismic testing, drilling and transport were measured in artificial polar bear dens of Prudhoe Bay, Alaska. It was concluded that the dry and wind-beaten arctic snow muffles both sound and vibrations extremely well and it seems unlikely that polar bears in their dens will be disturbed by the type of petroleum-related activities measured here, providing those activities do not take place within 100 m of the den.Key words: Ursus marifimus, seismic activity, conservation

Distribution of time lags between successive petroleum exploration activities

Four time lags are studied: (1) drilling activity behind seismic activity; (2) oil and gas reserves discovered behind drilling activity; (3) oil and gas production behind reserves discovered; and (4) oil and gas production behind drilling activity. A ridge regression method is used to estimate the distributions of these lags for 50 countries and regions active in petroleum exploration. A complete review of obtained results is given as well as an interpretation of estimated models and failed ridge regressions. Five types of distributions have been found: decreasing monotonically, unimodal, bimodal, uniform, and increasing monotonically. The distributions allow estimating the capital freezing in the exploration process and assessing the resulting policy made by all companies active in a country. For example, the actual exploration history in Poland is analyzed with the use of distributed time-lag approach and net present-value concept. An overinvestment in drilling in comparison with petroleum infrastructure has been stated on the basis of the excessive lagging of production behind drilling activity. A direction of further lag studies is also suggested.

Empirical Modelling of Canadian Petroleum Exploration Activity

Empirical Modelling of Canadian Petroleum Exploration Activity

Empirical Modelling of Canadian Petroleum Exploration Activity

Empirical Modelling of Canadian Petroleum Exploration Activity