This paper, which accompanies the preceding article by Gastil, reviews Cretaceous paleomagnetic evidence for Baja and coastal southern California. Like Cretaceous paleomagnetic data for the Cordillera as a whole, results from Baja and southern California require northward transport of 1000km or more, relative to interior North America. Agreement between independent results, for different rock types and experimental techniques, is overwhelming. Dextral shear driven by right-oblique subduction readily accounts for the paleomagnetic results. Alternative explanations such as experimental errors, rock-magnetic effects, anomalous geomagnetic behavior, errors in dating, or local structure are inadequate, improbable, or both. Some geologists have difficulty reconciling the findings of paleomagnetism with their own results; hence, as emphasized by Gastil, a conflict and enigma exist. To resolve them will require a willingness on both sides to honestly scrutinize basic assumptions.

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