USGS Logo Geological Survey Professional Paper 294—D
Stromatolites of the Belt Series in Glacier National Park and Vicinity, Montana
PLATES

PLATE 19.—SPECIMEN SHOWING CHARACTERISTIC STRUCTURES USED IN KEY TO IDENTIFICATION OF STROMATOLITES

The following figures accompany the key to the identification of stromatolites.

FIGURE

1. Cryptozoon occidentale Dawson
2. Collenia undosa Walcott
3. Collenia symmetrica Fenton and Fenton
4. Collenia multiflabella n. sp.
5. Collenia frequens Walcott
6. Newlandia lamellosa Walcott
7. Conophyton inclinatum n. sp.
KEY TO THE IDENTIFICATION OF STROMATOLITES IN THE BELT SERIES
[Figures are given on plate 19]
I. Incrusting forms, growth upwards from a point on the substratum by the addition of convex upward laminae Genus: Cryptozoon

A. Gross form turbinate.

1. Laminae conform to upper surface of colony in later stages of development.

a. Laminae smooth Cryptozoon occidentale, figure 1
II. Incrusting forms, growth upwards from a surface on the substratum by the addition of convex upward laminae Genus: Collenia

A. Gross form hemispheroidal or depressed spheroidal.

1. Laminae conform to upper surface of colony.

a. Laminae coarsely crenulate Collenia undosa, figure 2

b. Laminae smooth Collenia symmetrica, figure 3

2. Laminae conform to upper surface of colony only during later stages of development.

a. Laminae finely crenulate Collenia multiflabella, figure 4

B. Gross form irregularly cylindroidal.

1. Laminae flattened to strongly convex.

a. Laminae smooth Collenia frequens figure 5
III. Incrusting forms, growth upwards from a surface on the substratum by the addition of concave upward laminae Genus: Newlandia

A. Gross form hemispheroidal.

1. Laminae do not conform to outer surface of colony.

a. Laminae smooth Newlandia lamellosa, figure 6
IV. Colonies of nested conical laminae with basal apex attached to the substratum Genus: Conophyton

A. Gross form cylindroidal.

1. Axes of cylindroids at a low angle to bedding.

a. Laminae smooth Conophyton inclinatum, figure 7

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PLATE 20.—COLLENIA FREQUENS, CRYPTOZOON OCCIDENTALE, AND THE "MOLAR TOOTH" STUCTURE

FIGURE

1. Collenia frequens Walcott in Conophyton zone 2 (p. 133).

The underside of a biostrome of C. frequens, showing a basal view of the cylindroidal colonies. North wall, valley of the Middle Fork Flathead River, opposite mouth of Cy Creek.

2. Collenia frequens Walcott in Conophyton zone 1 (p. 133).

Closeup of a joint surface showing longitudinal section of cylindroids with very gently convex laminae. On trail about 1-1/2 miles north of Fifty Mountain Camp.

3. Collenia frequens Walcott in Conophyton zone 2 (p. 133).

Joint surface showing cylindroidal nature of colonies. Type site of Conophyton zone 2 at top of Running Rabbit Mountain.

4. Collenia frequens Walcott (X 1/2), in Collenia frequens zone (p. 133).

Closeup of a joint surface showing longitudinal section of cylindroids with strongly convex laminae. On trail just east of Appekunny Falls.

5. Cryptozoon occidentale Dawson (X 1/2), Siyeh limestone (p. 132).

Holotype of Collenia compacta Walcott. From Continental Divide at head of Kipp Creek. USNM 60712.

6. Collenia frequens Walcott, Siyeh limestone (p. 133).

This photograph, taken by Bailey Willis in 1901, is the only material on which Walcott based his description of the species. The following notes accompany the photograph: "Photo No. 325, Rock mass showing large concretionary or coralline masses in the Siyeh formation about 500 feet from top of the formation. Head of McDonald Creek. Ridge between McDonald and Logging Creeks near the summit, Montana. August 7, 1901."

7. "Molar tooth" structure, Siyeh limestone (p. 137).

The Garden Wall trail near Logan Pass.

8. Collenia frequens Walcott (X 1/2) (p. 133).

Holotype of Collenia albertensis Fenton and Fenton. From the Altyn limestone on the north slope of Gable Mountain. PUM 24021.

9. Collenia frequens Walcott (X 1/2) (p. 133).

Holotype of Collenia versiformis Fenton and Fenton. Note the similarity to specimen in plate 20, figure 8. PUM 24027.

10. Collenia frequens Walcott (X 1) (p. 133).

Part of colony showing fragmentary nature of collected specimens. Conophyton zone 2, in railroad-cut along Bear Creek opposite mouth of Devil Creek. USGS a117.

11. Collenia frequens Walcott (X 1/2) (p. 133).

Polished longitudinal section of cylindroid. Conophyton zone 2, on north side of trail about 4 miles up Ole Creek trail. USGS a249.

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PLATE 21.

FIGURE

1. Cryptozoon occidentale Dawson, Missoula group (p. 132).

Biostrome developed on surface of lenticular coarse sandstone. Upper surface of biostrome overlain by breccia composed of stromatolite fragments. Railroad-cut about 3 miles southeast of Nyack, Mont.

2, 3. Cryptozoon occidentale Dawson (X 1/2), Chuar group (p. 132).

Grand Canyon, Ariz. Walcott, in 1916, called these Collenia occidentale (Dawson). Owing to the present distinction between the two genera, it is necessary to refer these specimens to the genus Cryptozoon. USNM 60711 and 60710.

4. Collenia undosa Walcott (X 1/2) (p. 133).

This specimen, labeled the holotype of Collenia willisii Fenton and Fenton, does not appear to be the specimen figured by them (1937) as figure 1 of plate 11. PUM 24020.

5. Collenia undosa Walcott, Missoula group (p. 133).

Joint surface shows typical development of biostromes of C. undosa. Overlying rock is argillite. South of Walton, Mont., 1.2 miles, on U. S. Highway 2.

6. Collenia multiflabella n. sp. (X 1/2), from Collenia multiflabella zone at Logan Pass (p. 134). Holotype. USGS a118.

7. Collenia undosa Walcott, in Collenia undosa zone 2 (p. 133).

Upper surface of a biostrome, showing mammillate nature of colonies. Cirque between Clements Mountain and Mount Oberlin.

8. Collenia undosa Walcott, in Collenia undosa zone 2 (p. 133).

Colony underlain by finely laminated argillite; overlain by coarse calcareous sandstone. Stromatolite made up of alternating layers of pure limestone and argillite. Cirque between Clements Mountain and Mount Oberlin.

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PLATE 22.—CRYPTOZOON OCCIDENTALE, COLLENIA UNDOSA, AND COLLENIA MULTIFLABELLA

FIGURE

1. Collenia multiflabella n. sp., in Collenia multiflabella zone (p. 134).

Note expanding cylindroids in basal portion of stromatolite that are capped by later continuous laminae. At type site of zone, on east side of Logan Pass just above the point where Reynolds Creek plunges into St. Mary valley.

2. Lithoid tufa (X 1) from Pleistocene shore of Lake Lahonton (p. 145).

Note similarity to Collenia multiflabella n. sp., plate 22, figure 1. USGS a251.

3. Collenia symmetrica Fenton and Fenton, Siyeh limestone (p. 134).

East of West Glacier, Mont., 2.5 miles, on U. S. Highway 2. USGS a120.

4. Collenia symmetrica Fenton and Fenton, in Collenia symmetrica zone 2 (p. 134).

Two large colonies in upper right of photograph; note size compared with man at lower left. Just east of snowshed 7 on Great Northern Railway along Bear Creek.

5. Collenia symmetrica Fenton and Fenton, Siyeh limestone (p. 134).

Massive bed above the scale contains C. symmetrica overlain by edgewise breccia of stromatolite fragments. At west end of outcrop opposite intersection of North Fork Road and Going-to-the-Sun Highway at south end of Lake McDonald.

6. Collenia symmetrica Fenton and Fenton (X 1/2) (p. 134).

Holotype of Collenia clappii Fenton and Fenton. PUM 24026.

7. Collenia symmetrica Fenton and Fenton, Helena limestone (p. 134).

Near top of hill 0.7 mile east of western end of Mount Helena Scenic Drive, Helena, Mont.

6. Collenia symmetrica Fenton and Fenton, Siyeh limestone (p. 134).

Colony at left overlain by edgewise breccia. Near observation platform at Hungry Horse Dam, Mont.

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PLATE 23.—CONOPHYTON INCLINATUM, DENDRITIC TUFA, ?NEWLANDIA SP., AND NEWLANDIA LAMELLOSA

FIGURE

1. Conophyton inclinatum n. sp., in Conophyton zone 2 (p. 135).

Bedding surface does not coincide with axes of cones, which accounts for the rounded nature of the laminae near their apices. Along Great Northern Railway opposite point where Devil Creek flows into Bear Creek.

2. Dendritic tufa (X 1/4) from Pleistocene shore of Lake Lahonton (p. 145). USGS a578.

3. Conophyton inclinatum n. sp., in Conophyton zone 2 (p. 135).

Joint surface shows nearly circular sections normal to axes of cones. Locality same as that for figure 1 of plate 23.

4. Dendritic tufa (X 1/4), from Pleistocene shore of Lake Lahonton (p. 145). USGS a579.

5. Conophyton inclinatum n. sp. (X 1/4), from Conophyton zone 1 (p. 135).

Specimen found weathered out of zone on The Garden Wall trail near Haystack Butte. USGS a119.

6. Conophyton inclinatum n. sp., from Conophyton zone 2 (p. 135).

Holotype. Along Great Northern Railway tracks in Bear Creek valley, opposite mouth of Devil Creek. USGS a2.

7. ?Newlandia sp. (X 1/4), Prichard formation (p. 134).

Near Pinehurst, Idaho. Resembles Newlandia, however organic origin not certain. USGS a1.

8. Newlandia lamellosa Walcott (X 1/4), Newland limestone (p. 134).

Eight miles west of White Sulphur Springs, Mont. Note strongly concave lower surface of stromatolite and very gently concave laminae. USGS a250.

9. Conophyton inclinatum n. sp., in Conophyton zone 1 (p. 135).

Podlike bioherms with associated finely laminated off-reef deposits common only in this zone. Going-to-the-Sun Highway, 6.4 miles northwest of Logan Pass.

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PLATE 24.

FIGURE

1, 2. Recent algal mat (X 1), from shores of Carson Sink, Nev. (p. 145).

Top and side views, showing felt of intertwined algal filaments. Basal part consists of fine-grained sediment bound together by algal filaments. USGS a121.

3. Recent arborescent algal deposit (X 1/2), from Green Lake, N. Y. (p. 144).

Polished section. USGS a252.

4. Recent algal deposit (X 50), from Green Lake, N. Y. (pl. 24, fig. 3).

Photomicrograph of slide. Note lack of laminated microstructure. USGS a252a.

5. Collenia sp. (X 50) (p. 133).

Photomicrograph showing laminated microstructure. USGS a211a.

6. Collenia undosa Walcott (X 50) (p. 133).

Photomicrograph showing lamina made up of fine-grained calcite mosaic with coarser grained calcite above and below. USGS a206a.

7. Lithoid tufa from Pleistocene shore of Lake Lahonton (X 50) (pl. 22, fig. 2).

Photomicrograph of slide. Lighter areas are voids between laminae. USGS a251a.

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Last Updated: 18-Jul-2008