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USGS1948

Preliminary report on the stratigraphy and structure of the area of the Ipnavik River, Alaska

Geological Survey Party 1 returned to Umiat from Wolf Creek on August 5. Plans for the field season of 1947 called for geologic reconnaissance along part of the Ipnavik River and along the Colville River between the Ipnavik and Kurupa Rivers, to be completed before the end of the season. Since not much time remained and the traverse was long--about 70 airline miles--it was decided that the work would progress more rapidly if two parts of the traverse were worked at the same time. Accordingly, Robert F. Thurrell, Jr., and James H. Zumberge, geologists, were transported by plane from Umiat to the confluence of the Ipnavik and the Colville Rivers on August 8. From there they traversed down the Colville to the Kurupa River 1/. The other two members of Party 1, Karl Stefansson, geologist, and Elder W. Lebert, cook, remained in Umiat until August 14 when a small plane was finally available to transport them to a camp on the Ipnavik River, about 30 airline miles southwest of the junction of the Ipnavik and the Colville Rivers. The party reached the Colville River on September 2, and arrived at Umiat on September 6.

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USGS1952

Stratigraphy and paleontology of the Noatak and associated formations, Brooks Range, Alaska

A think complex sequence of olastic rocks, formerly named the Noatak formation, underlies the Lisburns formation (Mississippian) in the Brooks Range, northern Alaska. Five formations have been recognized as a result of of recent investigations by the author and other geologists of the Navy Oil Unit, U.S. Geological Survey. In the western Brooks Range, the three formations present below the Lisburns formation are: Utukok formation (Upper Touranisian to Lower Visean), Montak formation (restricted) (Upper Devonian to Lower Tournaisian (?)) and Hunt Fork (?) formation (Upper Devonian). In the central Brooks Range the Kayak formation (Lower to Upper Tournaisian), Kanayut formation (Upper Devonian to Lower Tournaisian (?)), and Hunt Fork formation (Upper Devonian) lie below the Lisburns formation. Lithologic and faunal characteristics of these sedimentary units reveal the regional pattern of sedimentation and suggest specific paleoecologic environments. The chart conglomerates in the Kanayut and Noatuk formations are thought to have formed in a belt characterized by fluctuating marine and nonmarine conditions, the chart source being a mid-Devonian ragolith. Analysis of formulas suggest certain correlations with the European, Siberian, and western Cordilleran sections. Described faunas of the Utukok and Kayak formations include 40 braciopod species and varieties, 9 echinodera species, 2 bryzoan species, 8 molluscan species, and 1 tribute species, of which 13 are new.

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USGS1950

Stratigraphy and structure of the Okpikruak and Kiruktagiak Rivers area, Alaska

Navy Oil Unit Party 4, during the summer field season of 1949, examined the surface geology of the area of the Okpikruak and Kiruktagiak Rivers. The party consisted of six men: two geologists, two field assistants, a weasel mechanic, and a cook. Three weasels were used for transportation in the field. The area covered is bounded on the west by the Okpikruak River, on the east by the Chandler River, and on the south by the north front of the Brooks Range. Tuktu Bluff on the Chandler River and its westward extension forms the northern boundary. The area is drained by the Chandler, Kiruktagiak, Ayiyak, Okokmilaga, and Okpikruak Rivers. The objectives of this summer's work was the geologic mapping and stratigraphic study of the rocks that crop out in this area. All outcrops were visited and the geology was plotted on vertical and trimetrogon oblique aerial photographs. Altitudes were established by an altimeter traverse. Parts of this area had been investigated previously by members of the Navy Oil Unit. During the summer of 1945 George Gryc, E. J. Webber, and Karl Stefansson visited outcrops along the. Chandler and Kiruktagiak Rivers and in the vicinity of Castle Mountain. In the same year L. A. Warner and C. E. Kirschner examined outcrops along the Okpikruak River in conjunction with their survey of the Klink and Colville Rivers. R. L. Detterman included detailed stratigraphic studies of cutbanks near the confluence of the Kiruktagiak and Chandler Rivers in his geological mapping of the lower Chandler during the summer of 1948.

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USGS1946

Preliminary report on the stratigraphy and structure of the Kurupa, Colville, and Oolamnagavik Rivers, Alaska

U. S. Geological Survey Party No. 4 covered the area between 68° 30' and 69° 08' N. latitude and between 154° and 155°20' W. longitude during the period May 18 to September 2. Traverses were confined mainly to the valleys of the Kurupa, Colville, and Oolamnagavik Rivers inasmuch as very little rock is exposed in the interstream areas. This report is limited to the Colville River valley area between the Kura and Killik Rivers, and to a stratigraphic section exposed. on the Kurupa 7-12 miles south of the Colville. A final report will be prepared by April 1, 1947, on the total area and will include discussions of the stratigraphy and structure of Upper Cretaceous formations A through D on the Oolamnagavik and Kurupa, the stratigraphy of Formation D on the Colville, and the Lower Cretaceous and Triassic rocks. Separation and identification of heavy minerals from the sandstones and conglomerates, binocular and petrographic microscope examinations of specimens, identification of megafossils, and separation and identification of microfossils, if any, will be undertaken. Detailed examination of all aerial photos will be made to trace out structures and formations in the adjacent areas to the east, north, and west. It seems probable that close correlation between this area, the Killik River area, and Maybe Creek area will be possible by extrapolating field and aerial photo data. It is possible also to trace structures and some formation westward from the Kurupa River.

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USGS1950

Stratigraphy and structure of the area of the upper Meade River, Alaska

The stratigraphic evidence in the upper Meade River area includes zones B to D of the Nanushuk group (Cretaceous). Zones B and C are not differentiated in mapping and description. South of the Meade River 2,100 feet of zones B-C and 1,500 feet of zone D are exposed. North of the fault zone along the Meade River, the only rocks present, estimated not over 1,000 feet thick, are zone D beds which may be at least in part younger than the zone D rocks south of the Meade River. Sands which barely meet the minimum requirements for potential reservoir beds are present in both zones. South of the Meade River the Kigalik anticline and the Falcon Creek anticline, both sharp-crested folds, trend east. The intervening synclines are broad with low dips on the flanks. Along the Meade River the major structure is a zone of reverse faults, about three-fourths of a mile wide, which brings rocks of zones B-C on the south opposite rocks of zone D on the north. Minimum displacement in this zone is 1,000 feet at longitude 157° 50'W. and 300 feet near the gas-seep lake. North of the fault zone, the Meade River anticline is a rather low fold, so poorly exposed that closure cannot be detected by surface geologic methods.

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USGS1946

Stratigraphy and structure of the area of the Killik, Chandler, Anaktuvuk, and Colville Rivers, Alaska

This report deals with results of field and laboratory studies carried out to May 1946 by the Geological Survey, largely as part of the Navy Department's program of petroleum investigations in northern Alaska. The immediate purpose of the work has been to collect and interpret stratigraphic and structural data pertinent to drilling in the Umiat area. Field studies were made during the summers of 1944 and 1945 in the drainage areas of the Colville, Killik, Chandler, and. Anaktuvuk Rivers (fig. 1). Paleontologic and microlithologic studies, together with stratigrahica1 and structural analysis of the areas, were carried out in the petroleum laboratory in Fairbanks. This work led. to preparation of a preliminary report submitted. in December, 1945. Additional detailed studies, in the Survey laboratories and offices in Washington, D. C., have resulted in some modification of earlier conclusions and changes in illustrations. The changes are minor and have no significant bearing on drilling in the Umiat area. The present report is accompanied. by revised conies of figures 1, 2, 3 (sheet 1) and. 5. These illustrations should be substituted for the comparable figures of the preliminary report. Figures 3 (sheet 2), 4, and. 6 of the earlier report stand unchanged and should, be added to the illustrations accompanying the present report. It is believed that work to date has revealed the general geologic picture of the area and. that the sequence of Upper Cretaceous rocks is established. The section of rocks in Umiat Test No. 1 has been approximately located within the sequence. This report, and the work on which it is based was done under the supervision of George O. Gates, who has contributed. much to the study.

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USGS1949

The Carbon Creek and Awuna anticlines

At the interim meting of the Technical Committee in Fairbanks, Alaska, in September 1949, the Navy Oil Unit was requested to make photo-geologic analysis of the Driftwood, Awuna, and Carbon Creek anticlines before the November meeting. A report on the photogeology of the Driftwood anticline, based on available air photos, has already been distributed. The present report considers the geology of the Carbon Creek and Awuna anticlines. The central part of the Carbon Creek anticline was studied in the field by party No. 2 during the 1949 season. A geologic report on this part of the anticline, by C. L. Whittington and Samuel A. Keller, will be distributed at the November meeting. The present photogeologic report covers the part of the Carbon Creek anticline from the western end of Whittington and Keller's area westward to the point where the Carbon Creek anticline plunges and disappears. A photogeologic map (fig. 1) accompanies this report and incorporates all available data both from the aerial photographs and from earlier field geologic studies of a part of the anticline by Thompson and Barksdale. The Awuna anticline has been mapped in the field by C. L. Whittington. A field geologic map of the anticline will be distributed at the November meeting. The discussion on the Awuna anticline in the present report is based in part on the field observations of Whittington and in part on a new study of the aerial photographs which had previously been studied by Whittington. In reading this section on the Awuna anticline, reference should be made to Whittington's geologic map, which will be available at the November meeting. At the present time, only trimetrogon photography is available for study of the western part of Carbon Creek and the Awuna anticline areas. Hence quantitative analysis of the structures is not possible, although rough estimates of the amount of plunge and of closures can be made. Accurate calculations of closure and plunge by photogrammetric methods must await the arrival of the vertical photographs of the area

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USGS1950

Preliminary report on selected sections of Lisburne Limestone, Brooks Range, Alaska

Location: - This report describes sections of the Lisburne limestone studied in the foothills and northern mountains of the Brooks Range, Alaska. The area covered extends along the front of the range from Sagavanirktok Lake (68°28' N. - 149°25' W.) west to the head of the Kukpowruk River (68°25' N. - 162°40' W.). The southernmost point in the area is at the head of Alapah Creek (68°11' N. - 150°40' W.) and the northernmost point is on Lisburne Ridge just west of the Etivluk River (68°36' N. - 156°40' W.). Field work was done by the authors at Sagavanirktok Lake, Kanayut Lake, Alapah Creek, the Anaktuvuk and Tiglukpuk Creek, and Chandler Lake. Brief visits were made to the Lisburne Ridge just north and west of the junction of the Nigu and Etivluk Rivers and to outcrops of Lisburne limestone along the Kiligwa River (68°30' N. - 158°35' W.). Data from other areas included in this report were collected by other field parties of the U. S. Geological Survey. A. L. Bowsher, Sr. .and J. T. Dutro, Jr. studied the Lisburne limestone at Kanayut Lake, Nanushuk Lake, and Itkillik Lake in 1949 1 / .W. W. Patton, Jr. and Irving L. Tailleur described the Lisburne limestone exposed in the northern Brooks Range along the Kiruktagiak River 2 / and the Okokmilage River 3 / in1949, and I. L. Tailleur and Bion H. Kent have supplied data on the Etivluk-Kiligwa Rivers area from their field work of 1950 4 /. R. M. Chapman, G. D. Eberlein, and C. D. Reynolds measured sections of Lisburne limestone at Kurupa Lake and on the east fork of the Etivluk River in 1950 5 /. E. G. Sable and M. D. Mangus measured the section on Iligluruk Creek near the head of the Kokolik River in 1950 6 /,, and Chapman end Sable measured the section at the head of the Kukpowrok River in 1949 7 /.

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USGS1947

Preliminary report on the stratigraphy and structure of the area of the Utukok River with notes on the Corwin-Cape Beaufort region, Alaska

U.S. Geological Survey Party 3 studied the geology of the Utukok River area and conducted a short reconnaissance of the Corwin-Cape Beaufort Region during the period May 12 to August 31, 1947. The upper part of the Utukok River was examined for several miles on either side while the lower, or Coastal Plain-portion, was necessarily limited to the few outcrops along the river. During this study, the major emphasis was placed upon rocks of Upper Cretaceous age and their relationships to the underlying Lower Cretaceous rocks. All macrofossils, and numerous samples for porosity, heavy mineral, and microfossil determinations were collected. A triangulation net was established by theodolite from Camp. 1 near the headwaters of the river to the mouth of Carbon Creek. The survey started and ended on measured base lines, and stations were determined by intersection and resection. Stations were selected, insofar as possible, on points that could be pin pricked on aerial photographs where adequate coverage was available, Horizontal control was computed for cartographic purposes. Vertical differences were computed from an elevation at Camp 1 assumed at 2,000 feet above sea level based upon two different airplane altimeter readings. Most of the country is too rough for wheel landings with the exception of several gravel bars in the river between Camp 6 and the coast. Pontoon landings with a Cub plane can be made at most places on the river. Driftwood, Adventure, Disappointment, Carbon, and Elusive Creeks are the main tributaries to the Utukok. At various localities, terrace gravels are common on divides of these streams. A terrace north of Driftwood Creek and about ten miles east of Camp 2 is covered with a deposit of gravel which is apparently, thick and is spread over an irregular area about two miles long and a half mile wide. A thin tundra cover obscures what is probably a much larger continuation of the gravel deposit. With favorable conditions plane landings could be made, but with a little construction work a commercial size airfield could be made.

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USGS1951

Preliminary report on the stratigraphy and structure of the Shaviovik and upper Sagavanirktok Rivers area, Alaska

During the 1951 field season, U. S. Geological Survey Navy Oil Unit party 1 conducted stratigraphic and structural studies of the rocks in the area between the westernmost fork of the Shaviovik River and the East Kuparuk River. This area is drained by the Sagavanirktok River and its major tributaries; the Echooka River, the Ivishak River, and Lupine River. Owing to the nature of the investigation, the studies were confined to a relatively narrow geographic strip, rarely exceeding a distance of 20 miles north of the northernmost occurrence of the Lisburne limestone of the Brooks Range province. The work was thus conducted in an area of approximately 2,000 square miles, which lies wholly within the Brooks and Arctic Foothill provinces; within this area approximately 1,000 square miles was mapped geologically. The party consisted of six men: A. S. Keller and R. L. Detterman, geologists; I. W. Marine and D. E. Reed, field assistants; L. G. Barbin, cook-field assistant; and T. F. Derrington, weasel mechanic. The party utilized 3 weasels for transportation of equipment and personnel during the season, during which time 15 camps ware established. Work was initiated on the Shaviovik River on May 24, 1951, and the party concluded its investigations on the Kuparuk River drainage on August 24, 1951. In 1947, G. Gryc and E. H. Lathram conducted reconnaissance studies of the rocks in the vicinity of camps 12-15 (pl. 1); and during the same year, G. Gryn visited outcrops on the Ivishak River in the vicinity of camps 6-7 (pl. 1). These studies were made by the Navy Oil Unit of the U. S. Geological Survey in conjunction with the investigations of NPR-4. No other work of a geologic nature had been done in the area in the past. The primary objective of the 1951 party was the correlation of the Mesozoic and upper Paleozoic strata of the foothills province west of the Itkillik River, with that of the Shaviovik and Canning Rivers region. A secondary objective was to determine the cause of the pronounced northeasterly swing in the trend of the Brooks Range front in the Sagavanirktok drainage and to determine the structural implications of this swing. The area was mapped at a scale of 1:20,000 on vertical photographs and transferred to trimetrogon drainage maps at a scale of 1:48,000 and 1:96, 00. An altimeter traverse was carried concurrently with the geologic mapping.

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USGS1947

Preliminary report on stratigraphy and structure of the area of Kigalik and Awuna Rivers, Alaska

During the summer of. 1947, U. S. Geological Survey Party No. 2 made a reconnaissance survey of the area between Awuna River and the divide north of the Kigalik River. The westernmost observations were made along the Awuna anticline to longitude about 157°30' W. and along the Kigalik anticline to longitude about 156°55'W. The easternmost work was done along the Knife Blade Ridge anticline at a longitude of about 154°30'W. Not all of this area was traversed, but a general idea of the area studied may be had by noting the distribution of dip and strike symbols on Figure 1. Parts of this area had been previously visited by Smith 1/ in 1927 as a part of his traverse from Allakaket to the Arctic Coast. In the period from about July 10 to August 5 his party ascended the Awuna River and Birthday Creek, portaged over the Kigalik-Awuna divide at Birthday Pass, and descended the Kigalik River to its mouth. Various parties in the field season of 1946 worked in areas not far distant. Webber 2/ began his field work near the headwaters of the Meade River and measured a section across the Kigalik anticline about 25 miles beyond the westernmost observations made on that structure by Party No. 2. Work by Chapman and Thurrell 3/ along the Colville River parallels at a distance of three or four miles work by Party No. 2 in the vicinity of Knife Blade Ridge. The easternmost observations by Party No. 2 in the vicinity of Knife Blade Ridge are about 11 miles west of the area south of Maybe Creek mapped by Ray and Fischer.4/ Of the 1947 work of other field parties that of Thurrell 5/ along the Colville River is most closely related to this report. His thickness from the base of Zone A to his Trace No. 5 is included in Column 1 of Figure 3. Webber's work 6/ along the Ikpikpuk and Titaluk Rivers is also in a closely related area. Party No. 2 moved through this area by weasel, the weasels being used extensively on the daily traverses. The party assembled at Umiat late in May and was flown out to a lake about one mile west of the Ikpikpuk River at latitude 69°40' N. where the weasels and initial supplies had been previously cached. Early in June the party moved south into the area in which it was to begin work. For the next several weeks the party worked in the area north of the Kigalik River, moving westward along the divide north of that river. At this time considerable work was done south of the Kigalik River, west of longitude 154°40'W. No closure was detected along the Kigalik anticline. Shortly after the middle of July the party moved southwestward to the vicinity of the Awuna anticline where a westerly plunge had been suggested from the study of aerial photographs. The general route of the party from then on was eastward along the divide between the Awuna and Kigalik Rivers. Due to the need to reach a food cache further east very little data was gathered in the area between Birthday and Section Creeks. It was intended to work this area by one or two spike trips from the camp at the head of Section Creek. However, after constructing a cross-section from data gathered by the party along Section Creek and by Thurreli in the area between the Colville and Awuna Rivers it became apparent that the strata exposed along the axis of the Awuna anticline were stratigraphically below the base of Zone A. It thus appeared that there would be little point in attempting to gather additional data in the area between Birthday and Section Creeks. The party continued eastward, working along the south flank of the Kigalik anticline. On September 1, the party camped about one mile west of the summit of Knife Blade Ridge. Because of unfavorable weather at this time only a small amount of field work was accomplished in the next week. Enough data was gathered to give a general picture of the structure here, but the data on stratigraphy and structure is far from exhaustive. On September 9 the party moved eastward, camping that night about 3 miles northeast of :Wolf Creek, and arriving at Umiat on the afternoon of September 10. Aerial photographs were carried in the field and used to record the points at which observations were made. A considerable amount of data was recorded on the photographs. Approximate elevations were obtained, at first by aneroid barometers, and later by more sensitive airplane altimeters. Plane table and alidade were used in local traverses in the area north of the Kigalik River to obtain dips and strikes by the 'three-point method. Nearly all other dips and strikes recorded were measured by Brunton compass. Dips of 5° or less in the area south of the Kigalik River should, in general, be considered as dip components with only the approximate strike shown. These low dips were taken on bedding traces* where it was usually impossible to observe an accurate strike with the Brunton.

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USGS1949

Summary of microfossil investigations, April 1948 to April 1949 with special reference to the south Barrow and Simpson areas

This report summarizes the results of microfossil investigations for he past year. It includes the microfossil data from the two South Barrow Test Wells and studies of samples from outcrop material an from seismograph shot holes. In addition, new information bearing on the special study of microfossils from the Cape Simpson area is presented. The ostracoda that have been recently studies are discussed in a separate report by Professor R. M. Swain.

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USGS1950

Review of the stratigraphy and structure of the Gubik anticline

At the direction of Ralph L. Miller, a special study was made of part of the Gubik anticline east of the Colville River. The purpose of this study was two fold; first, the examine the field evidence bearing on east plunge, second, to attempt to establish the continuity of the anticlinal axis from the Colville River to the Anaktuvuk River. The results of this study and a summary of results of the study of part of the anticline west of the Colville River by Stefansson and Thurrell 1/ are presented below.

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USGS1950

Stratigraphy and structure of the Aupuk anticline

In addition to conducting an examination of the surface geology in the Southern Foothills province between the Killik River and east fork of the Etivluk River, Navy Oil Unit Party No. 5 was requested to map the Aupuk anticline during the 1950 field season, for the purpose of evaluating the petroleum possibilities thereof from the standpoints of favorable statigraphy and possible structural closure. Field mapping of the Aupuk anticline began on August 1, and about 1 month was devoted to the study. Party personnel consisted of G. Donald Eberlein and Charles D. Reynolds, geologists, W. L. D'Olier and W. D. Carter, field assistants, Richard Olson, camp cook, and Max H. Davis, weasel mechanic. Robort M. Chapman, geologist, visited the party for 1 week early in August to help start the work and shared, with Eberlein, the responsibilities associated with the final compilation of this report. Three weasels were used for daily transportation to the field and for moving camp. A 10-foot Link boat equipped with 5 hp. outboard motor was used to cross the Colville River. As field work progressed from west to east it became apparent that the camp equipment and weasels would have to be gotten across the Colville River if field work was to be completed by early September. This crossing was effected without incident at a point approximately 10 miles below the confluence of the Kurupa and Colville Rivers on August 26. The party reached Umiat on September 5.

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USGS1951

Stratigraphy and structure of the upper Siksikpuk - Nanushuk Rivers area

Structural and stratigraphic studies of tha rocks in the Siksikpuk and Nanushuk Rivers area were conducted by Navy Oil Unit party 2 during the summer field season of 1950. The field party consisted of two geologists, two field assistants, a cook, and a weasel mechanic. Three weasels were used for transportation of equipment and personnel. The area examined covers approximately 1,000 square miles of the Arctic Foothills province and lies between the Itkillik River on the east and the Chandler River on the west. The area is drained by the Itkillik, Nanushuk, Anaktuvuk, Siksikpuk, and Chandler Rivers. The mapped area adjoins the Okpikruak and Kiruktagiak Rivers area 1/ to the west. The primary objective of the geologic work in this area was detailed stratigraphic study of pre-Nanushuk group rocks in the Southern Foothills belt as a supplement to the Work begun in the Okpikruak and Kiruktagiak Rivers area in 1949. A secondary objective was areal mapping and structural studies for the purpose of delimiting structures favorable for drilling tests of the Lisburne limestone. Parts of this area had been reconnoitered by members of the U. S. Geological Survey in previous years. In 1901 F. C. Schrader traversed the Anaktuvuk River, In 1945 R. E. Fellows, R. M. Chapman, and C. T. Bressler visited outcrops along the northern margin of the area in the vicinity of the Anaktuvuk River and Kanayut Creek. E. J. Webber and R. L. Detterman examined a few of the cutbanks along the Nanushuk River in 1947; and in 1949 A. L. Bowsher, Sr., and J. T. Dutro mapped an outlier of Lisburne limestone north of Nanushuk Lake.

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USGS1951

Stratigraphy and structure of the southern foothills section between the Etivluk and Kiligwa Rivers

The part of the Southern Foothill section, Arctic foothills province, that lies beteween the Etivluk and Kiligwa Rivers was investigated by Navy Oil Unit party 6 during the 1950 field season, A belt about 16 miles wide and 60 miles long (approximately 800 square miles) was mapped in considerable detail (see index map, pl. 1). The mapped area is in the west-central part of the Arctic Foothills province, wholly within the boundaries of Naval Petroleum Reserve No. 4. Major drainage consists of the middle reaches of the Etivluk, Ipnavik, Kuna, and Kiligwa Rivers. Principal objectives of the party, using previous geologic studies in. the Okpikruak-Kiruktagiak Rivers area 1/ ao an initial working base, were stratigraphic and structural studies of the outcrops in the interstream areas. In view of the former interest in possible Lisburne limestone plays, the Lisburne Ridge west of the Etivluk River and the northward nosing of the Triassic complex between the Ipnavik and Kuna Rivers were designated as areas for particular emphasis. The party included six men: two geologists; two field assistants, a cook, and a weasel mechanic. Three weasels were available for transportation; two of which were maintained in operating condition for daily field use. As many exposures as were pertinent or accessible were examined. Vertical photographs were used for plotting data and for areal control; relative vertical control was established with altimeters, The effective working radius from base camp as increased from 8 miles to 20 miles by making frequent 2- or 3-day spike trips.

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