Microfossil slides examined were from Atlantic Richfield Susie Unit no. 1, northern Alaska sent by Richard E. Anderson of Atlantic Richfield and Andrew Marianos of Humble Oil and Refining Co. An assemblage of well preserved arenaceous Foraminifera and a smaller assemblage of calcareous species of Late Cretaceous (Turonian-Senonian) age were identified on slides from core and ditch samples from the interval of 1160 feet through at least 7212 feet. Foraminifera in samples from depths from the lowest thousand feet of this interval are not as well preserved nor as readily identifiable as those from 1160-6141 feet. More than 20 species are the same as those known from the Schrader Bluff and Seabee Formations. These include such species as Haplophragmoides rota Nauss, H. kirki Wichenden, H. bonanzensis Stelck and Wall, large specimens of Saccammina lathrami Tappan (common in Upper Cretaceous beds of northern Alaska), Ammodiscus cretaceous (Reuss), Verneuilinoidas fischeri Tappan, Verneuilinoides sp. (a massive form), Gaudryina sp., Dorothia sp. Arenobulimina torula Tappan, Trochanmina ribstonensis Wickenden. T. whittingtoni Tappan, Eoeponidella aff. E. strombodes Tappan, Pullenia cf. P. cretacea Cushman, Praebulimina carseyae (Plummer), P. venusae (Nauss), Nonionella taylorensis Hofker, Causcasina vitrea (Cushman and Parker), Quinqueloculina sphaera Nauss, Neobulimina canadensis Wickenden, Neobulimina albertensis (Stelck and Wall), and a large species of Hedbergelia.

Many of the ditch samples from depths below 7212 feet carry some of the species from the Upper Cretaceous beds; the sidewall core samples from the same depths are barren except for a specimen of Trochammina sp. in a sample from 7361 feet. This has a few chambers and resembles T. webbi Stelck and Wall from the central part of the Kaskapau Formation, Spirit River, Alberta, Canada, but may have closer affinities to T. mcmurrayensis Mellon and Wall from the McMurray Formation of Albian age in Alberta.

Fossils of Cenomanian age were not recognized and there is very little evidence of Albian age Lower Cretaceous fossils in samples from this well. Those found are few and scattered. Entirely lacking is a sharply defined Verneuilinoides borealis fauna of middle to late Albian age so common over much of the foothills of northern Alaska and in the subsurface of many of the coastal plain wells. Possibly nonmarine beds of Early Cretaceous age may be extensively developed in the area of this well, or else there is a tremendous thickness of Upper Cretaceous beds.

A few specimens of what appear to be Verneuilinoides borealis were observed on slides from core 10 (9235-9245 ft.). In a sample from 10,091 feet, from core 11 (10,091-10,099 ft.), occur a specimen of Quadramorphina ruckerae (Tappan) and a specimen of Conorboides umiatensis (Tappan), two forms heretofore identified only from Albian beds in northern Alaska. Four specimens of Conorboides umiatensis also occur on a slide from a ditch sample at 8440 feet. Two specimens that are possibly Haplophragmoides topagorukensis Tappan of Albian age occur in a ditch sample from 7830 feet and in a side wall core sample at 10,042 feet a questioned H. topagorukensis was noted. Albian fossils are wanting in other samples and the ditch samples carry Upper Cretaceous Foraminifera. Questioned specimens of Verneuilinoides borealis Tappan occur on slides of ditch samples from 7550 feet and 8440 feet.

In summation, beds through at least 7212 feet are of Late Cretaceous (Turonian and Senonian) age. Beds of Early Cretaceous (Albian) age are identified from Foraminifera in the last two cores (9235-9345 ft. and 10,09-10,099 ft.) and in a ditch sample at 8440 feet. Possible Albian forms occur higher at 7361 feet, 7550 feet, and at 7830 feet. The test well does not have a prominently defined zone of Lower Cretaceous fossils. A “boundary” between Colvile and Nanushuk beds may be somewhere between 7212 feet and 7361 feet.

The accompanying faunal chart indicates identifications and distribution of fossils in the material examined.

Explanation:
Number of specimens (3) less than 12
Rare (R) specimens (few, not counted)
Common (C) specimens (12-15)
Abundant (A) specimens (16-50)
Very Abt. (V) specimens (over 50)
Fragment (f)
Atlantic Richfield samples (At.ditch, At.sidewall, cores)
Remaining samples from Humble Oil & Refining Co.