THE OKDOVICIAN SYSTKM 



Oirvan District. 



Moffat District 



( DRUMMUCK BEDS, 400 feet 

 b. Shales with Staurocephaltis. 



a. Shales with Trinudeus 



seticornis. 



SHALLOCH FLAGS, 800 feet 

 Flagstones and shales with 

 . Dicellograptus truncatus. 

 NViiiTKHOusK BEDS, 300 feet 



b. Beds with Dicellograptus 



complanatus. 



a. Beds with Leptogr.flaccidus. 

 AuinvKi.i, FLAGS, 1000 feet 



b. Beds with Dicrano. ra-mosus 



and Diplograptus rugosus. 

 a. Beds with Crypto, tricornis 



&ndDiplograptusfoliaceus. 

 BALCLATCIIIE BEDS, 100 feet 

 Grits and sandstones with 



Climacograptus bicornis 



and Cryptogr. tricornis. 

 Shales with Glossograptus 



Hincksi. 



HAUTKELL SHALES, 100 feet 



6. Zone of Dicellograptus an- 

 ceps and D. truncatus. 



5. Barren imidstones. 



4. Zone of Dicello. complanatus. 



3. Zone of PJ-eurograptus fine- 

 aris and Lepto. flaccidus. 



2. Zone of Dicranograptus 

 Clingani and D. ramosus. 



1. Zone of Climacogr. Wilsoni 

 and Cryptogr. tricornis. 



BEXAN CONGLOMERATE, 500 feet. 

 STINCHAR GROUP, 100 feet 

 b. Shales with Didymograptus 

 supcrstes and Dicello- 

 graptus sextans, 

 a. Limestones with Maclurea 



Logani. 



KIRKLAND BEDS, 200 feet 

 Sandstones and conglomerates 



with Orthis conjinis. 

 Unconformity here. 



GLENKILN SHALES, 50 feet- 

 Black shales with Didymo- 

 graptus superstes, Duel, 

 sextans, and Diplograptus 

 dentatus. 



Yellow mudstones with chert- 

 bands. 



Black shales with Ccenograptus 

 graeilis and Didymo- 

 graptus super stes. 



RADIOLARIAN CHERTS, red and 

 grey cherts, mudstones, and 

 volcanic tuffs, 70 feet. 



Black shales of Bennane 

 Head with Tetragraptus 

 quadribrachiatus, 4 feet. 



VOLCANIC ROCKS, lavas and tuffs 

 with thin shales containing 

 Tetr. quadribrachiatus, 1500 

 feet seen. 



RADIOLARIAN CHERT BEDS 



Mudstones and shales with 

 layers and lenticular 

 nodules of chert, 150 to 

 200 feet. 



Volcanic tuffs at Trowdale, 

 150 feet Base not seen. 



