DEVONIAN SECTION ALONG ABITIBI RIVER 373 



DETAILED SECTION OF DEVONIAN STRATA EXPOSED ALONG ABITIBI RIVER 



Devonian system 



Upper Devonian series 



Long Rapids shale '^?n''?e''ef ^ 



13. Shale, in alternating layers of gray and dark color ; 

 exposed in the west bank of river, about the middle 



of Long Rapids 20 



12. Shale, black, somewhat laminated, containing nu- 

 merous spores of Sporangites huronense ; exposed 

 in the west bank where a syncline crosses the river 



valley near the middle of Long Rapids 35 



Abitibi River limestone — about 110 feet 



11. Shale, calcareous, in layers 4 to 10 inches thick, al- 

 ternating with irregular nodular layers of about 

 equal thickness; exposed beneath the black shale, 

 number 12 above, from which it is separated by a 

 sedimentary break; containing the fossils listed 



below : 8 



Lcptostrophia of. perplana. 

 Schuchertella chemungensis var. 

 Productella cf. productoides. 

 Schizophoria iowensis. 

 Leiorhynchus near glol)uUformis. 

 Leiorhynchus near kelloggi. 

 Leiorhynchus aff. mesacostalis. 

 Atrypa missouriensis. 

 Atrypa reticularis. 

 Cyrtina hamiltoncnsis var, 

 Cyrtina hamiltonensis. 

 Spirifer near subvaricosus. 

 Delthyris sculptilis. 

 Reticularia aff. Iwvis. 

 Athyris fultonensis. 

 10. Limestone, irregularly bedded, partly dolomitic, with 

 few or no fossils ; exposed in the upj;)er part of 

 Long Rapids and also at the mouth of Abitibi River 

 and near the mouth of the Kwataboahegan River . . IS 



9. Limestone, shaly, or calcareous shale, with few or no 

 fossils ; exposed along the river bank near the 



upper end of Long Rapids 3 



8. Dolomite, brown, in thin layers, the lower 3 feet a 

 distinct coral reef; containing the species listed 

 below ; exposed a short distance above the outcrops 



of 9 and 10 above 12 



Acervularia davidsoni. 

 Acervularia near profunda 

 Favosites alpenensis. 

 Alveolites sp. 

 Aulopora sp. 

 Ccratoporn sp. 



