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merged in - articles had same name
==Basis for each level==
==Basis for each level==
Most of the levels and sublevels (outlined above) are necessary to adequately describe, in the classification scheme, all of the different elements that characterize a trap. Each level has its own unique basis for classification. Trap systems are based on the controlling geologic elements that created the traps, trap regimes are based on the geologic processes that caused the traps in each system, traps classes are based on the geometry and composition of the traps within the trap regimes, and trap families are based on the genesis or origin of the traps within the trap classes.
Most of the levels and sublevels (outlined above) are necessary to adequately describe, in the classification scheme, all of the different elements that characterize a trap. Each level has its own unique basis for classification. Trap systems are based on the controlling geologic elements that created the traps, trap regimes are based on the geologic processes that caused the traps in each system, traps classes are based on the geometry and composition of the traps within the trap regimes, and trap families are based on the genesis or origin of the traps within the trap classes.
==Workflow==
Classifying traps is interpretive. As more data become available, the trap classification can change or be modified. Different explorationists may classify a particular trap in completely different categories, depending on their particular viewpoints.
Traps can be classified formally or informally. An informal classification is descriptive; little knowledge is needed to classify a trap beyond learning how to describe it. A formal classification is more rigorous and requires knowing the structure of the scheme proposed in this chapter.
==Informal classification==
[[file:classification-of-exploration-traps_fig2-1.png|thumb|{{figure number|2-1}}.]]
An informal classification is a description that conveys a general or specific impression of a trap. For example, East Anschutz Ranch field, shown in the map and cross section below, could be informally classified as an anticlinal trap. This informal classification conveys a very general impression of the trap. Informal classification can also be more specific. For example, we might classify East Anschutz as an elongated asymmetric anticline with a gently dipping back limb and a steeply to overturned forelimb.
==Formal classification==
[[file:classification-of-exploration-traps_fig2-2.png|thumb|{{figure number|2-2}}See text for explanation.]]
A formal classification conveys more information than an informal classification. It is also more rigorous. The diagram below shows the formal classification for East Anschutz Ranch.
==Procedure==
The table below lists the procedure for classifying a trap.
{| class = "wikitable"
|-
! Step
! Action
|-
| 1
| Determine the trap system: structural, stratigraphic, or fluidic.
'''If''' More than one element controls the trap Go to step 2
'''Then''' Only one element controls the trap Go to step 3
|-
| 2
| Determine the primary, secondary, and (if necessary) tertiary trap system.
|-
| 3
| Determine the trap regime. What process formed trap closure?
|-
| 4
| Determine the trap class. Which class best describes trap geometry, or which class describes compositional makeup of the reservoir or seal or fluid that creates or defines trap boundaries?
|-
| 5
| Determine the trap family. What is the genesis of trap closure?
|-
| 6
| If necessary, use intermediate groupings (superclasses, superfamilies, sub- classes, styles, subfamilies, styles, varieties) to give fuller descriptions.
|}
==See also==
==See also==
* [[Classification philosophy]]
* [[Classification philosophy]]
* [[What is a trap?]]
* [[How to use the classification scheme]]
* [[Classifying combination traps]]
* [[Classification basis]]
* [[Classification basis]]
* [[Trap classification levels]]
* [[Trap classification levels]]