Stratigraphic traps are formed by the presence of contrasting rock types or stratigraphic features that create barriers to the movement of hydrocarbons, such as changes in rock porosity, permeability, or the presence of unconformities. These traps can result from the deposition of sediments in different environments over time, leading to variations in rock properties that can trap hydrocarbons. Additionally, structural processes like faulting or folding can further enhance the trapping mechanisms in stratigraphic traps.
Hydrocarbon traps that form in geologic structures such as folds and faults are called structural traps. Hydrocarbon traps that result from changes in rock type or pinch-outs, unconformities, or other sedimentary features such as reefs or buildups are called stratigraphic traps.
The largest oil field in Texas is the Spraberry Trend, which is a type of stratigraphic trap. In Alaska, the largest oil field is the Prudhoe Bay field, which is a type of structural trap. In the Gulf of Mexico, the largest oil fields are the Perdido and Mars-Ursa fields, which are also structural traps.
An isopach map is created by connecting points of equal thickness on a stratigraphic unit. It is used in geology to show the variations in thickness of a particular stratigraphic layer across a region. This map can help in identifying areas of deposition, erosion, or structural changes within the subsurface geology.
The boundary between two sedimentary rock layers is called a bedding plane or stratigraphic boundary. It represents a break in the deposition of sediment, marking a change in the environment or conditions under which the rocks were formed.
A layer of ash and lava is a geologic feature formed by the deposition of volcanic ash and solidified lava during volcanic eruptions. These layers can build up over time to create thick sequences of volcanic material, which can be preserved in the rock record as distinct stratigraphic units.
Hydrocarbon traps that form in geologic structures such as folds and faults are called structural traps. Hydrocarbon traps that result from changes in rock type or pinch-outs, unconformities, or other sedimentary features such as reefs or buildups are called stratigraphic traps.
Oil traps share the common function of capturing and holding hydrocarbons, allowing them to accumulate in subsurface reservoirs. They typically consist of a combination of geological features, such as impermeable rock layers (cap rocks) that prevent the oil from migrating further, and porous rocks (reservoir rocks) that store the oil. Common types of oil traps include structural traps, like anticlines and fault traps, as well as stratigraphic traps formed by changes in rock layers. Ultimately, their formation is crucial for the discovery and extraction of oil resources.
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Robert Ernest Butler has written: 'Paleontology and stratigraphy of the Cynthiana formation' -- subject(s): Geology, Stratigraphic, Paleontology, Paleontology, Stratigraphic, Stratigraphic Geology, Stratigraphic Paleontology
Thomas D. Hamilton has written: 'Quaternary stratigraphic sections with radiocarbon dates, Chandler Lake quadrangle, Alaska' -- subject(s): Geology, Geology, Stratigraphic, Stratigraphic Geology 'Quaternary stratigraphic sections with radiocarbon dates, Wiseman quadrangle, Alaska' -- subject(s): Geology, Geology, Stratigraphic, Stratigraphic Geology
B. S. Norford has written: 'Ordovician and Silurian stratigraphy of the southern Rocky Mountains' -- subject(s): Geology, Geology, Stratigraphic, Stratigraphic Geology 'Correlation chart and biostratigraphy of the Silurian rocks of Canada' -- subject(s): Geology, Stratigraphic, Paleontology, Stratigraphic, Stratigraphic Geology, Stratigraphic Paleontology, Stratigraphic correlation 'The Silurian fauna of the Sandpile Group of northern British Columbia' -- subject(s): Paleontology 'Ordovician and Silurian biostratigraphy of the Sogepet-Aquitaine Kaskattama Province. No. 1 Well, northern Manitoba' -- subject(s): Borings, Geology, Stratigraphic, Stratigraphic Geology
The primary global time-stratigraphic unit is a system.
Two types of traps:Fault (structural) trapStructural traps are formed by a deformation in the rock layer that contains the hydrocarbons. Domes, anticlines, and folds are common structures. Fault-related features also may be classified as structural traps if closure is ‎present. Structural traps are the easiest to locate by surface and subsurface geological and geophysical studies. They are the most numerous among traps[citation needed] and have received a greater amount of attention in the search for oil than all other types of traps.An example of this kind of trap starts when salt is deposited by shallow seas. Later, a sinking seafloor deposits organic-rich shale over the salt, which is in turn covered with layers of sandstone and shale. Deeply buried salt tends to rise unevenly in swells or salt domes, and any oil generated within the sediments is trapped where the sandstones are pushed up over or adjacent to the salt dome.Stratigraphic trapsStratigraphic traps are formed when other beds seal a reservoir bed or when the permeability changes (facies change) within the reservoir bed itself. Stratigraphic traps can form against either younger or older time surfaces.
The largest oil field in Texas is the Spraberry Trend, which is a type of stratigraphic trap. In Alaska, the largest oil field is the Prudhoe Bay field, which is a type of structural trap. In the Gulf of Mexico, the largest oil fields are the Perdido and Mars-Ursa fields, which are also structural traps.
George Vincent Cohee has written: 'Rotary drilling in Illinois' -- subject(s): Oil wells, Oil well drilling, Equipment and supplies '... Lateral variation in Chester sandstones producing oil and gas in lower Wabash river area' -- subject(s): Geology, Geology, Stratigraphic, Petroleum, Stratigraphic Geology 'Changes in stratigraphic nomenclature by the U.S. Geological Survey, 1969' -- subject(s): Geology, Stratigraphic, Nomenclature, Periodicals, Stratigraphic Geology 'The recent impetus to oil prospecting in Illinois' -- subject(s): Petroleum 'Changes in stratigraphic nomenclature by the U.S. Geological Survey, 1975' -- subject(s): Geology, Stratigraphic, Nomenclature, Stratigraphic Geology 'Changes in stratigraphic nomenclature by the U.S. Geological Survey, 1971' -- subject(s): Geology, Stratigraphic, Nomenclature, Stratigraphic Geology 'Recent developments in oil and gas in Illinois' -- subject(s): Petroleum, Natural gas 'Changes in stratigraphic nomenclature by the U.S. Geological Survey, 1965' -- subject(s): Formations (Geology), Geology, Stratigraphic, Nomenclature, Stratigraphic Geology
Norman L. Hatch has written: 'Redefinition of the Hawley and Goshen schists in western Massachusetts' -- subject(s): Formations (Geology), Geology, Nomenclature, Petrology, Schists, Stratigraphic Geology, Stratigraphic correlation 'Some suggested stratigraphic relations in part of Southwestern New England' -- subject(s): Nomenclature, Stratigraphic Geology, Stratigraphic correlation
Gerald William Thomas has written: 'Stratigraphic paleontology of the Morgan formation, Uinta Mountains and vicinity' -- subject(s): Geology, Stratigraphic, Paleontology, Stratigraphic Geology