74 



SHORTER CONTRIBLTTIONS TO GENERAL GEOLOGY, 1921. 



Unconformity. 



Kaibab limestone: Feet. 



Ilarrisbiirg Efvpsiferous member: Limestone, 

 varying in character in different layers, 

 some of the upper ones pinkish and sun 

 cracked, others showing a coarse matrix 

 with mnch angular chert. Still other lay- 

 ers have much whitish chert with platy 

 ft'acture, and some in the lower part of the 

 unit resemble the older part of the Kaibab 

 with dark chert. Variation in character 

 laterally is very great. Three collections 

 at al)Out the same horizon at dil'ferent places 

 near the top of the limestone show the fol- 

 lowing fossils: (1) I'rodurtiis ioisi, I'usluJa 

 subliorrida; (2) Lilhoslrotion? n. sp.. Fiivo- 

 silcs' n. sp., Campophyllum:' n. sp.; (3) Di- 

 fhisma sp., Nucula levatiformis, Lcda ohesa, 

 Ptrria {Bahewcllia?) ap. . Pseudomonotisl' sp., 

 Sikizoduswhedm? , Pleurophorusmeximnus, 

 PliKjioglypla cnnna, Biicannpsis alf . B. beUa, 

 E}iphemu9 sp., Goniospira sp., Pleurotoma- 



rui sp., Niiticopfiis.' . Platiicrraa sp 2.'i0 



Shale, yellow, gypsiferous 30+ 



ISwIioncmilmuod liy the log of llie wrll of llic Nirgiii I>(mie oil Co,] 



Kaibal) limestone: 



J/imestone of varying hardness and color and 

 some gypsum, composing the Ilarrislnu-g 

 gypsiferous member, 2-58 feet. As well 

 mouth is 12 feet lieneath top of IlarrisVmrg 

 member tlie thickness is close to that found 

 on surface [2"0] 



Limestone, light colored, containing much 

 chert -75 



limestone, salmon-colored, soft 38 



Limestone, etc. (details not known) 466 



Thickness of Kaibab limestone 1, <>49 



(^oconino sandstone and Supai formation: 



Sandstone to bottom of well 1, b'j'* 



15. Sedioii ill Ihc Wiishinf/li)n dome, '! miles east of St. 



George, Utah. 

 Moeiikopi formation: Feet. 



\'irgiii limestone member 160± 



Lower red-beds member 320± 



Rock Canyon conglomeratic member: 



Limestone, dark gray, thin bedded, witli 

 some light-colored limestone; contains 

 Bakewellia n. sp. (small fnrml and .1///"- 



phorieisp 10 



Shale, dark red, with gypsum stringers 33 



Concealed interval, possibly red shale 57 



Coarse conglomerate of limestone and chert 



in a limestone matrix, the whole pinkish. 11 

 Shale, red and yellow, some of it sandy ... 5 

 Lime.«time, coarse, pinkish, with chert 



fragments "^ 



Concealed , i>robably shale 8 



Limestone, pinkish, containing large 



boulders of limestone and chert 20 



Limestone, gray, rough, silicified, with 

 some chert nodules 12 



Moenkopi formation — Continued. 



Rock Canyon conglomeratic member — Contd. Feet. 

 Coarse conglomerate of limestone in a lime 

 matrix grading ujiward into a gypsum 



matrix 53 



Gyiffium, pure, massive 10 



Limestone, ]5orous, gray, somewhat silic- 

 ified 2 



Gypsum with mucli fine-grained plaf\' 

 drab to dark-gray limestone; some 



breccia 83 



Unconformity. 

 Kaibab limestone: 



Tlarrisburg gypsiferous member alisent locally, 

 but present here and there and containing 

 Schizodus sp., PUigioglypta ranna?, Bellem- 

 phon majuscubis', Goyihsspira sp., Enomphn- 

 lus sp., Naiitihis sp. 

 Massive cherty gray limestone. 



16. Section (it tlie BItiomington dome, 5 miles south of St. 



George, Utah. 

 Moenkopi formation: Feet. 



Virgin limestone memlier ]30± 



Lower re<i-beds member: Shale, red, some of it 

 sandy, and gyp.sum. Near base contains 

 gypsum with thin limestones and Bnki leellia 

 n. sp. ('small form) 320± 



Unconformity. 

 Kaibab limestone: 



Tlarrisburg gypsiferous member: 



Limestone, gi'ay, filled with angular pieces 

 of chert that break into plates. This 

 unit is crumbly, and weathered edges 

 of blocks are rounded 12 



Limestone, like unit above, but in a single 

 bed, harder and weathering into angular 

 blocks with included chert projecting 

 as browm excrescences on surface 2 



Breccia of quartz fragments loosely ce- 

 mented l)y limestone; fi-iable and non- 

 resistant 1 



Limestone, gray, coarse, granular 3 



Limestone, .gray, very soft, nonresistant . . . 6 



Gypsum 4 



Limestone, white, .granular; weatheis to 

 [lowder. Contains partly silicified fos- 

 sils, including Polypora sp., Chonctes 

 hillaniis', Sejucim iilarin gmuhdiipensis, 

 Composita n. sp 5 



Limestone, dark gray, coarse graine<l, fria- 

 ble, nonresistant; fossiliferous 5 



Limestone,- gray, thin bedded, with nod- 

 ules of chert ' 



Gypsum, pinkish, with a 5-foot bed of dark 



limestone 10 feet above base 215 



Limestone, gi-ay, filled with fragments of 

 chert that 1 ireaks into plates 5 



Concealed interval 5 



Limestone, soft, graj-, with well-preserved 

 silicified fossils 5 



Thickness of Harrisburg member. 



