652 W. T. LEE STRATIGRAPHY OF COAL FIELDS OF NEW MEXICO 



Mesaverde -< 



Feet Inches 



Shale 5 



Sandstone, principally massive, light gray, friable 

 in some places with brown flinty concretions. 

 Thickness varies from place to place, but the 

 lower 50 feet or more forms a prominent cliff — the 

 basal sandstone of the Mesaverde — and contains : 

 Hahjmen'ites major Lesq. : Mactra sp. related to 

 M. alta M. and H. ; and several gastropods and 

 other shells similar to those found below the 

 basal sandstone 300± 



Mancos 



Shale with thin layers of gray sandstone ; consti- 

 tutes the transition zone from the shale below to 

 the base of the Mesaverde; contains Ostrea ele- 

 gantula Newberry?; Anomia sp. ; Inoceramiis sp. 

 related to /. proximiis Tuomey ; Inoceramus sp. 

 related to /. darahlni Morton ; Cucullcea sp. ; 

 Cardium sp. ; Cyprimeria sp. ; Legiunen ? sp. ; 

 Corhula sp. ; Mactra t sp. ; Anatina sp. ; Denta- 

 lium sp. ; Turritella gallsteoensis Johnson ; Vo- 

 l\itomorpha sp. ; Voliitoderiual sp. ; Nautilus 

 dekayl Morton ?; Scapliites sp. related to >Sf. hip- 

 pocrepis De Kay ; Baculltes sp. ; Place nt ice ras 

 sancarlosense Hyatt; Placcnticeras planum Hyatt 

 (U. S. G. S. localities Xos. 7164 and 7165) 150± 



Shale, dark-colored, with fossiliferous concretions 



of limestone near the top and near the bottom. . 2.100 



Sandstone (Tres Hermanos), hard, quartzose in 

 thin, irregular layers ; weathers yellowish brown ; 

 contains shells, numerous worm borings, and in- 

 definite markings of various kinds ; also Haly- 

 menites major Lesq.; Pinna petrina White?; 

 Pecten sp. ; Gyrodes sp. ; Turritella sp. (U. S. 

 G. S. locality No. 710S) 20 



Shale, dark-colored, with dark brown concretions 

 of impure limestone (Gastropod zone) and a 

 stratum of "crinkly" sandstone one foot thick 

 near the middle 75 



Conglomerate containing pebbles of quartz and 

 chert up to an inch in diameter 2 



Shale, carbonaceous, with coal a few inches thick 

 near the top 5 



Sandstone (Dakota), hard, quartzose, massive, 

 cross-bedded, locally conglomeratic near the base. 50± 



Sandstone, white, more evenly bedded than the 

 hard sandstone overlying it 40± 



Shale and sandstone, variegated in color SO 



Conglomerate, cross-bedded, massive; pebbles an 

 inch or more in diameter 10 



Shale, variegated, and sandstone (Morrison), thick- 

 ness estimated 200 



3,689 



