A criteria-based methodology for determining the mechanism of transverse drainage
 development, with application to the southwestern USA

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Interactive Criteria-Based Decision Making Process to Evaluate a Transverse Drainage

This interactive figure color codes each mechanism and their associated criteria.  CLICK on the individual criteria for examples to become more familiar with the possible evidence associated with each transverse drainage mechanism.  Some criteria support multiple mechanisms and are thus boxed multiple times.  If a criterion occasionally supports a mechanism, but not always, the box is dashed.  This is an earlier version, the most updated is available CLICK HERE.

Below are some examples (in black and white) to illustrate how the diagram is used:

Example 1: Virgin River Gorge (Site 1 in Table 5), an example of an antecedent transverse drainage with a low level of confidence. In this coded diagram, criteria associated with antecedence are boxed in black, the next darkest shading represents superimposition, the intermediate shading piracy, and the lightest overflow.  Some criteria support multiple mechanisms and are thus boxed multiple times.  If a criterion occasionally supports a mechanism, but not always, the box is dashed.  The pattern-shaded criteria indicate the noted criteria for the Virgin River Gorge (Site 1 in Table 5).  The available evidence fails to distinguish whether the Virgin River is older or younger than uplift or the most recent exposure of the Beaver Dam and Virgin Mountains.  Because some criteria offer conflicting results, antecedence is only offered as speculatively.

Example 2: Eastern Grand Canyon (Site 7 in Table 5), an example of an overflow transverse drainage with a moderate level of confidence. In this gray coded diagram, the criteria associated with antecedence are boxed in black. The next darkest shading represents superimposition, the next lightest piracy, and the lightest overflow.  Some criteria support multiple mechanisms and are thus boxed multiple times.  If a criterion occasionally supports a mechanism, but not always, the box is dashed.  The pattern-shaded criteria are associated with the eastern Grand Canyon (Site 7 in Table).  The downstream sedimentological evidence indicates the Colorado River post-dates uplift of the Kaibab Plateau, and possibly the most recent exposure of the highland from beneath a covermass.  The accumulated criteria generally support overflow, but some evidence offers support for piracy and superimposition.

Example 3: Canyon De Chelly (Site 8 in Table 5), an example of a superimposed transverse drainage with a high level of confidence. In this gray coded diagram, the criteria associated with antecedence are boxed in black. The next darkest shading represents superimposition, the next lightest piracy, and the lightest overflow.  Some criteria support multiple mechanisms and are thus boxed multiple times.  If a criterion occasionally supports a mechanism, but not always, the box is dashed.  The pattern-shaded criteria are associated with Canyon De Chelly (Site 8 in Table 5).  Transverse drainage gravels atop the bedrock high clearly indicate the drainage pre-dates the most recent exposure of the bedrock high.  The remaining available evidence supports superimposition for Canyon De Chelly with little evidence of alternate explanations.