MAItVLANO (if:o[,()(iI(AL SURVKY 



71 



X. Sirtioii iif liliifl' luie mile hrlow I'h/ii:h ('reck. 



Neoceue. 



Eocene. 



s s 



^ fe 



Ff(<t. Ini-lifH. 



Diutoiniiceous eartL 40 



Brown >;lauconitlc clay tmicli oxidized in places. ... 2 

 Band of pinkish-brown clay nodules in ^laucunltic 



clay 



Dark f^lauconitic clay witii many fossil casts : 4 



Concretions with occasional fossils i) 



Arffillaceous ^jreensand with many casts and occa- 

 sional shells 3 



■{ Concretions with many large specimens of Jfeivo- 



f/los.iii I Home If i 



Arijillaceous greeusand with abundant fossils in- 

 cluding Jferelrir xii(ihit//ressii, Veiieriennlin potupit- 

 coctimix, Ilerrof/loxsH tnomeiji, Turritellii iioloiinirviiniH, 

 Mesalia obruta, Protoeardin leiiin. Modiolus ahiljunt- 

 enxin, Corbuhi xiihenf/oiintti, Mitrn /lotoiiinrtuiiis, and 

 many other farms (Zone 17) K 



Total 5(5 



Other Sections. 



Along none of the other drainage lines is the sequence of Eocene 

 strata as complete as in the Potomac river area. Several important 

 local sections, composed of one or more members of the series, have 

 been observed at man}' different points and may be correlated with one 

 or the other of the divisions previously referred to. Some of the more 

 important and typical sections follow. . 



Section in ravine three-quarterx of a tnile east of Oxen, Prince George^s Connttj. 



Feet. Inches. 



I' Yellow glauconitic sand .5 



• Indurated ledge 4 



. g I Black shell marl 4 



T- .2 5 ! Indurated ledffe with 0.s/;-t'" (■cM>(»;-e.'i.'(iro.'<?;-</ c, 



c :i I Shell marl, lower part packed with soft shells in- 



■^ 2 I eluding CKcxUaea giganien, Oxtrea compreiisi rostra, 



P-i I Jferetrix ovata ror. pyga Boxitiiopsix leTificulariM, 



[^ CraxsatelUtes alaeforiniii, Turritella humeroxa 10 



Total Ut 10 



Section in Railroad cut near Seat PhoMint, Prince George's Connttj. 



Feet. 

 Pleistocene. Gravel and loam 12 



. =s I Glauconitic shell marl with Ostreo compre.ssi rostra 5 



~ S I Indurated ledge with 0-strea compren-nrostra, Jfodiolus alabam- 

 Eocene. S- "§ "j eusis, Crns.<iateUitcs alaeformis, CorbuJa sp., etc 8 



< 'i \ ' — 



S 1^ Total -2.5 



