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Geological Survey Professional Paper 294D
Stromatolites of the Belt Series in Glacier National Park and Vicinity, Montana
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PLATES
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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. |
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| 1. Laminae conform to upper surface of colony in
later stages of development. |
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| 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. |
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| 1. Laminae conform to upper surface of colony. |
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| 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. |
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| a. Laminae finely crenulate |
Collenia multiflabella, figure 4 |
| B. Gross form irregularly cylindroidal. |
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| 1. Laminae flattened to strongly convex. |
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| 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. |
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| 1. Laminae do not conform to outer surface of colony. |
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| 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. |
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| 1. Axes of cylindroids at a low angle to bedding. |
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| a. Laminae smooth |
Conophyton inclinatum, figure 7 |
(click on image for a PDF version)
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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.
(click on image for a PDF version)
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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.
(click on image for a PDF version)
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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.
(click on image for a PDF version)
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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.
(click on image for a PDF version)
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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.
(click on image for a PDF version)
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pp/294-D/plates.htm
Last Updated: 18-Jul-2008
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