Abstract Developing a philosophy of exploration is an important step toward becoming a more effective explorationist, both individually and on a team. This chapter discusses various aspects of exploration philosophy with the intent of helping individuals develop their own philosophies.

Abstract Traps are the product of the interaction of many geologic elements and processes. The outcome of all the possible combinations of geologic elements makes each trap unique. Yet each trap generally shares enough similarities with other traps in the same basin or in other basins that traps may be classified. The classification chosen depends on one's purpose. The ultimate purpose of the trap classification presented in this chapter is to facilitate the discovery of oil and gas accumulations. This chapter discusses the philosophy of classification, shows how to classify traps in a scientifically rigorous and systematic way and presents a classification scheme for traps found to date. The classification scheme is designed to be flexible and therefore will evolve as new trap types are found and trapping concepts change.

Abstract The ultimate goal of the explorationist is to find and develop commercial accumulations of hydrocarbons, and the focus of all efforts should always be directed toward this objective. North (1985, p. vii) states, “Geology is an integrative science and among its many constituents, petroleum geology is the most integrative of all.” The successful petroleum geologist must be able to integrate and understand information from a wide variety of sources, including organic and inorganic geochemistry, geophysics, well logging, sedimentology, stratigraphy, paleontology, structural geology, and economics. As of yet, no direct method of precisely identifying the presence and location of a commercial oil and gas accumulation has been developed. Typically, most accumulations are hidden in the subsurface under thousands of meters of overlying sedimentary cover. Therefore, the explorationist must rely on a variety of indirect indicators to identify potential locations of hydrocarbon accumulations and if these indicators are judged to be strong enough, the drilling of an exploratory well will be required to prove or disprove the presence of the accumulation.

Great Basin is a term used to describe a portion of the Basin and Range Physiographic Province that has internal surface drainage (Fig. 1). The entire basin is characterized by horst and graben blocks, generally oriented in a north-south direction, formed by Cenozoic extensional faulting. The major grabens form present-day valleys, and the large horst blocks form the intervening mountain ranges. This chapter describes the oil accumulations that have been discovered in the area to data, and discusses the potential for finding additional hydrocarbon accumulations. Only truncation fault-block traps located within grabens are productive at this time. Potential exists, however, for commercial accumulations in folded structures, some of which are thrusted, in both horst and graben blocks. In addition, regional subcrop traps also have high potential in the area, as do local stratigraphic traps, especially in the Diamond Peak and Chainman sandstones of Mississippian age. The truncation fault-block traps discovered to date range in size up to 15 to 20 million barrels of oil reserves. Because excellent mature source rocks and reservoirs, along with good potential traps, are present in some parts of the Great Basin, the possibility exists for undiscovered resources.