of
Sample: Sample No. 70APa236 -- USGS No. 24455-PC, Upper Paleozoic loc. M1043
Locality: Field No. 70APa236
Description: 1000 ft. S. of top of Heart Mtn.; from thin limestone lens in pillow basalts that border southern edge of Brooks Range near Bettles. Collector: W. W. Patton, Jr. 1970.
Location: Alaska Quadrangle: Wiseman
Lat.: 67o05' " Long.: 152o28' "
Reference
Title: Report on Referred Fossils ,  1970 (10/15)
[Report date was not given. Date material received is used here - NZ]
Report by: J. Thomas Dutro , Jr.
Referred by: William W. Patton , Jr.
Age: Permian
Comment:This single large collection contains much echinodermal debris, fenestrate and ramose bryozoans (including Dyscritella? and Stenopora?) and several corroded valves of the brachiopod Odontospirifer. The spiriferoid was first described from the Permian of East Greenland and has since been reported from the Canadian Arctic Islands, northern Alaska, Wrangell Mtns., and the Tahkandit Formation. Some of the bryozoans are similar to those reported by Helen Duncan from the Ramparts Formation and are also like forms from the Sadlerochit Formation (Echooka Member) in northeastern Alaska. The age is, therefore, Permian and most probably mid-Permian or younger.
Occurrence(s)
No. Group Name Qty Notes
1 Bryozoans Dyscritella? sp.
2 Bryozoans Stenopora? sp.
3 Brachiopods Odontospirifer sp.
4 Echinoderms Echinodermal debris

Title: Report on Referred Fossils ,  1971 (12/14)
Samples are from a thin limestone lens in pillow basalts that border southern edge of Brooks Range near Bettles. Wiseman quad. Coll: W. W. Patton, Jr.; W. P. Brosge, 1970. Long. 152 deg. 28’ W., lat. 67 deg. 05’ N., 1,000 ft south of Heart Mountain.

This collection has been assigned USGS Upper Paleozoic loc. M1043. Paleontological determinations follow:

The origin and deposition of these carbonate rocks and in particular the grainstones and packstones is in 50 feet or less of water on a shallow-open shelf platform. These bioclastic carbonates were deposited near or at the living site of the organisms which formed the fossil fragments. The preservation of the large and delicate bryozoan fragments argue against long transportation, such as in a turbidite current from the platform to deposition into deep water.

The presence of glauconite in grainstones and packstones is common in carbonate rocks all over the world despite the fact that it is a mineral of reducing environment. Stratigraphic observation and studies indicate that glauconites are associated with zones of slow deposition, often forming in strata which are overlain later by an unconformity. It seems reasonable that under conditions of very slow deposition conditions exist for the organic reworking of sediment as well as mechanical reworking. Grains are carried down into the substrate in a reducing environment in which iron is concentrated (probably also by slow intermittent deposition during which time no clastic material is introduced to mask it). Later such grains are exposed to water action by marine channeling, further burrowing and during the interim glauconite has formed from the mud and organic slime caught within them while they have remained buried. These glauconitic packstones tell us that not only slow deposition prevailed but that sufficient mud occurred to create impermeability and a reducing iron-rich environment. Most pore-filling glauconite is basically a product of organic feces in the mud.

One of the best papers written on the environment of deposition of the late Paleozoic bryozoan-echinoderm-wackestone-packestone facies was published by R. C. Murray and F. J. Lucia in the 1967 Geological Society of America Bulletin, v. 78, p. 21-36. A Xerox copy of their abstract and figure 7 is enclosed. Figure 7 may well represent a model in which your Permian bryozoan-echinoderm wackestones-packestones were deposited.

Report by: Augustus K. Armstrong
Referred by: T. P. Miller
Age: Permian
Comment:Bryozoan-echinoderm packstone; broken and rounded bioclasts up to 4 mm in diameter. Sorting and packing suggest current deposition, near wave base in relatively shallow water, less than 50 feet. Bryozoan and crinoid fragments indicate normal open marine conditions.
Occurrence(s)
No. Group Name Qty Notes
1 Bryozoans Bryozoan
2 Echinoderms Echinoderm