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.