Geologic Map of Alaska: Marble, northern Alaska

Marble, northern Alaska

Unit symbol:	Pzcn
Age range	early Paleozoic (541 to 323.2 Ma)
Lithology:	Metamorphic
Group name:	Marble

Ranges from light-gray to white, partly recrystallized limestone to coarsely crystalline marble to dark, finely crystalline dolomitic marble. Subordinate interbedded calc-schist, chloritic schist, and quartzite. Unit ranges in age from Ordovician to Mississippian and may locally include rocks as old as Cambrian. Contains scattered fossils (Patton and others, 2009). Primarily exposed in the Baird Mountains quadrangle

Source map information

Source map	Patton, W.W., Jr., Wilson, F.H., Labay, K.A., and Shew, Nora, 2009, Geologic map of the Yukon-Koyukuk basin, Alaska: U.S. Geological Survey Scientific Investigations Map SIM-2909, 26 p., 2 sheets, scale 1:500,000.
Symbol	Pzca
Unit name	Carbonate rocks
Description	Ranges from light gray to white partly recrystallized limestone to coarsely crystalline marble. Dark finely crystalline dolomitic marble. Interbedded calc schist, chloritic schist, and quartzite in subordinate amounts. Unit ranges in age from Ordovician to Mississippian and may locally include rocks as old as Cambrian. Distributed along northern edge of map area from Baird Mountains and Selawik quadrangle on the west to Wiseman quadrangle on the east. Occurs as scattered bodies within schistose and phyllitic rocks of units PzPxsa, PzPxua, and Pzpa and as tectonic blocks in the mélange unit KJm
Lithology	Sedimentary

Correlated geologic units

Label	Dm
Description	Marble, northern Alaska, Paleozoic
Geologic age	Cambrian to Mississippian
Geologic setting	Sedimentary, carbonate

Lithology	Form	Importance
Marble < Metacarbonate < Metasedimentary < Metamorphic		Major
Limestone < Carbonate < Sedimentary	Bed	Major
Mica-schist < Schist < Metamorphic		Indeterminate, major
Dolostone < Carbonate < Sedimentary	Bed	Indeterminate, major
Phyllite < Metaclastic < Metasedimentary < Metamorphic		Minor