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Reference
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| Title: |
Report on Referred Fossils
,
1973
(03/16)
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Twenty nine microfossil samples designated as the 72ARr200 sequence were collected in the Sadlerochit Mountains, SW 1/4 Sec. 2, NW 1/4 sec. 11, T. 3 N., R. 29 E., Mt. Michelson quadrangle. The samples were collected through 1100 feet of slaty siltstone which is overthrust on the south by the Katakturuk Dolomite of Silurian-Devonian? age, and is in contact to the north with the Lisburne Group(Mississippian). Although considered a Paleozoic sequence by geologists of the Alaskan Branch, a microfossil check was requested as a member of an oil company orally reported finding Mesozoic Forams in this same sequence of rocks. Samples were washed in Menlo Park--all have been carefully examined but no microfossils were found except for a single specimen of a possibly arenaceous foraminifer in one sample, but if this belongs to the genus suggested it has no value for age determination as the range is from the Silurian to the Recent. In checking these samples, each was screened into 4 grade sizes for better examination. Only a cursory examination was given the coarsest fraction, but one to 4 trays of each of the other 3 grade sizes were examined. Therefore, I believe the material has been adequately checked and the absence of microfossils lends support to the Paleozoic interpretation of the field men. Details of the individual samples follow. |
| Report by: |
Harlan Bergquist
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| Referred by: |
H. N. Reiser
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| | Age: | Ordovician-Quaternary |
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| Comment: | Washed residue consists of particles of clay with very rare rounded quartz grains. In the finest fraction one microfossil was found. This is a tiny discoidal Saccammina-like arenaceous specimen which has no age significance as the genus Saccammina and kindred arenacoues forms have a long geologic range (Ordovician and Silurian to Recent). |
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| Title: |
Report on Referred Fossils
,
1973
(04/09)
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| Report by: |
Harlan Bergquist
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| Referred by: |
H. N. Reiser
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| | Age: | No Data |
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| Comment: | this is in response to your memo of April 3 accompanying the washed remainder of sample 72ARr200 (1050 ft.), which you submitted to determine if any more microfossils could be found to supplement the Saccammina-like form reported for that sample in my E and R of March 16, 1973. The new material was examined microscopically in 3 grade sizes but not another foraminifer or any other microfossil was found. Regretfully this is the same negative result I had with the earlier cut of the sample which I rewashed and reported on in an E and R of April 7th. The washed residue in the cut most recently submitted is essentially the same as previously reported for the sample. |
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