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Abstract The Ligurian cycle has a duration approximately equivalent to Early Jurassic times. This major transgressive/regressive facies cycle is characterized by several rifting events that are related to the development of the Ligurian Tethys. Its onset is marked by the Early Cimmerian unconformity dated as latest Norian. Its end corresponds to the Mid-Cimmerian unconformity, dated as Late Toarcian (Stille, 1924), which preceded the late Aalenian major regression linked with tectonic uplift known in many areas of northern Europe. One result of this uplift phase was the coeval rapid and major subsidence phase that allowed the accumulation of thick successions in the major half-grabens of the nascent Tethyan margin. The Ligurian cycle can be subdivided into three or four 2nd-order facies cycles, depending on the local tectonic development in the area. The whole cycle comprises 27 3rd-order depositional sequence cycles. These can be dated locally to the precision of an ammonite "horizon". Our sections are located along a north-south transect, from the Hebrides basin in the northern U.K. to the Alpes Maritimes in southern France. The study areas are located in the southeastern France Basin (now involved in Subalpine folding), the Causses (southern Massif Central of France), the Quercy (eastern Aquitaine) and the Paris Basin. These are compared with the Wessex, Cleveland and Hebrides basin in the U.K. Documentation is provided by ammonite biostratigraphic studies and outcrop and subsurface data. Such data have been reinterpreted using sequence-stratigraphic methodologies. One of the key results is that the 3rd-order depositional sequences that are the building blocks of the longer term cycles are correlatable units the entire western European craton.

ABSTRACT This field trip guide presents a summary of the Paleozoic bedrock geology of the Twin Cities (Minneapolis and St. Paul) region as well as an introduction to the Quaternary depositional and erosional history of the Twin Cities area, focusing on the carving of the Mississippi River gorge by glacial River Warren. Within this geological context, the philosophy behind a variety of pedagogical techniques is discussed, together with student learning goals, opportunities, and objectives for each locality.