Selected Paleozoic Sections of Alaska 



Thickness, Feet 



Selected Paleozoic Sections of Alaska 



Thickness, Feet 



ermian 

 Kandik district 



\ississippian 

 Porcupine district 



Koyukuk-Melozi 



district 

 Yukon-Tanana 



district 



Limestone 



Conglomeratae, shale, 

 and sandstone 



Tahkandit 

 limestone 



Wiseman-Chandalar 



district 

 Marshall district 

 Sheenjek district 



Dark shale and limestone, in part same as 

 Calico Bluff formation 



Greenstone, little rhyolite, formerly consid- 

 ered part of Kanuti group 



Clay shale, sandstone, conglomerate. Na- 

 tion River formation 



Lava flows and associated sediments. Ram- 

 part group and Circle volcanics 



Limestone, shale, slate. Calico Bluff forma- 

 tion 



Limestone beds 



Undifferentiated schist, shale, chert, quartz- I 

 ite 



Chert with minor amount of limestone and 

 shale, Livengood chert 



Comparable with northern Alaska section 



Andesite and basalt flows and tuff 



Dark limestone, somewhat silicified, weath- 



4-6000 

 5-10,000 



13,000 

 2-4000 



• 



ering light, with argillaceous and arena- 







ceous beds 



6000 plus or minus 





Quartzite, conglomerate, shale, with cherty 



r 





matrix 





Chisana district 



C ' a) : sla,e i ] Wellesley 

 Shale and conglomerate > 



formation 

 Conglomerate 



1-2000 



)evonian 



Upper 





Wiseman-Alatna 



Quartzite, sandstone, slate, little conglom- 





district 



erate, grit, limestone 



? 



Wiseman-Chandalar 



Quartzite, flint, calcareous black slate, im- 





district 



pure limestone. Formerly part of West 







Fork formation 



? 



Eagle district 



Basalt lava and pyroclastics of greenstone 







habit. Woodchopper volcanics 



10,000 plus or minus 





Middle 





Porcupine district 



Brown shale and basalt 



Massive light gray-blue limestone. Salmon- 







trout limestone 



300 



Kandik district 



Argillite, chert, and cherty grit 











Central-East 



district 

 Wiseman-Chandalar 



district 

 Kantishna-Nenana 



district 



Chisana-Tok 



district 

 Sheenjek district 



Silurian 



Porcupine district 



Sheenjek-Alatna 

 Kandik district 



Preacher-Tolovana- 

 Hot Springs district 



Ruby district 

 Ordovician 



Porcupine district 

 Ruby district 



Preacher district 



Cambrian 



Kandik district 



Kandik district 



Thin beds dark gray limestone, shale, and 

 chert 



Lithographic limestone, dark gray crystal- 

 line limestone 



Clay shale, siliceous slate, chert, quartzite, 

 sporadic limestone, and conglomerate 



Slate with small amounts of limestone 

 Massive limestone, equivalent to part of^ 



Tonzona 

 Limy shale, more calcareous at top 

 Slate, argillite, graywacke, quartzite 

 Black conglomerate, white conglomerate, 



shale and graywacke 

 Crystalline limestone associated with black 



slate, sandy beds, somewhat schistose 

 Quartzite, sandstone, slaty sandstone, and 



argillaceous sediments 



Middle 

 Black fissile shale, little siliceous limestone 

 Buff magnesian limestone 

 Slate, schist, thin layered limestone; Skagit 

 Massive somewhat siliceous limestone; Skagit 

 Massive white to cream limestone 

 Calcareous and dolomitic limestone, some- 

 what recrystallized. Tolovana limestone 

 Lower 

 Undifferentiated limestone 



Middle 

 Gray limestone 

 Magnesian limestone overlain by calcareous 



limestone, not differentiated on map 

 Volcanic tuff and associated igneous rocks 

 Black shale, merging downwards into schist 



Upper 

 Limestone, with dark gray to black 



and chert in higher part 

 Limestone 



Middle 

 Upper plate of limestone 

 Thin layers of slate an quartzite 

 Lower plate of limestone 



slate 



1000 

 500 



> 10,000 plus or minus 



2500 plus 



3000 plus 



600 



5000 

 ? 



