Eight major carbonate types are widespread in the Lisburne Group of northern Alaska and Yukon: (1) bryozoan-crinoidal recrystallized packstone; (2) bryozoan-crinoidal mudstone and wackestone; (3) crinoid-pelletoid recrystallized packstone and grainstone; (4) pseudo-oolitic grainstone; (5) oolitic grainstone; (6) bryozoan grainstone; (7) spiculite packstone; and (8) dolomitic limestone and dolomite. These facies are present in the Wachsmuth, Alapah, and Wahoo Limestones, and the Kogruk and Nasserak Formations.

The most favorable facies for foraminifers is the pseudo-oolitic grainstone which abounds in the Wahoo Limestone. Crinoid-pelletoid recrystallized packstones and grainstones also yield a good archaediscid fauna. Endothyrid assemblages are present in the bryozoan-crinoidal wackestones of the Wachsmuth Limestone. Spiculites are usually devoid of foraminifers; hence zonation of the Lisburne Group in the western part of Alaska must be based mostly on macrofaunal evidence.

Twelve consistent foraminiferal assemblages can be recognized in the northern part of the American Cordillera: (1) a late Tournaisian (Zones 8 and 9) tournayellid assemblage (Septatournayella-Tournayella); (2) and early Visean (Zones 10-11) Earlandia facies (first appearance of Globoendothyra); (3) an early middle Visean (Zone 12) Eoendothyranopsis spiroides microfauna; (4) a late middle Visean (Zone 13) Eoendothyranopsis pressa-rara assemblage; (5) an early late Visean (Zones 14-15) Brunsia facies; (6) a Meramec-Chester boundary assemblage (Zone 16_i), characterized by the elimination of many "Meramecian" elements such as Eoforschia, Eoendothyranopsis, etc.; (7) a latest Visean (Zone 16_s) Neoarchaediscus-Planospirodiscus assemblage; (8) an earliest Namurian (Zone 17) Asteroarchaediscus fauna; (9) an early Namurian (Zone 18) Biseriella assemblage; (10) a middle Namurian (Zone 19) Quasiarchaediscus?-Eosigmoilina? assemblage; (11) a late Namurian (Zone 20) Lipinella-Millerella-Globivalvulina assemblage; and (12) Zone 21, the youngest assemblage recognized in the Lisburne Group, characterized by the outburst of numerous fusulines including Eoschubertella and Pseudostaffella.

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