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Preston E. Hotz Ralph J. Roberts,

... with intercalated volcanic rocks and pyroclastics. The eastern assemblage is on the order of 15,000 feet thick in most places; the western assemblage is much thicker, probably more than 50,000 ... The depositional environments of the eastern and western assemblages were clearly different. The eastern assemblage is miogeosynclinal, the western eugeosynclinal. The two have ... the Roberts Mountains thrust--which carried the western assemblage relatively eastward or southeastward over the eastern assemblage. ...

Tópico(s): Geological and Geochemical Analysis

1958 - American Association of Petroleum Geologists | AAPG Bulletin

Artigo Revisado por pares

Wallace M. Cady,

... between Quebec and Maine.Two contrasting intergradational lithic assemblages, the graywacke-shale assemblage and the carbonate-quartzite assemblage, characterize the protolith of the bedded rocks. The graywacke-shale assemblage includes thick sections of lower Paleozoic strata, portions ... eastward away from the foreland. The carbonate-quartzite assemblage laps both unconformably and gradationally eastward over the graywacke-shale assemblage in sections of the middle Paleozoic east of ... and fossiliferous strata, chiefly of the carbonate-quartzite assemblage, have escaped metamorphism. It is also fairly clear ...

Tópico(s): Geological and Geochemical Analysis

1960 - Geological Society of America | Geological Society of America Bulletin

Artigo Revisado por pares

Ralph Gordon Johnson,

... ANALYSIS OF THE MODE OF FORMATION OF FOSSIL ASSEMBLAGES RALPH GORDON JOHNSON RALPH GORDON JOHNSON DEPARTMENT OF ... ANALYSIS OF THE MODE OF FORMATION OF FOSSIL ASSEMBLAGES. GSA Bulletin 1960;; 71 (7): 1075–1086. doi: ... Abstract Theoretical aspects of the formation of fossil assemblages are explored for the purpose of obtaining criteria ... Models are developed which represent: (1) a death assemblage preserved under conditions of rapid burial; (2) an assemblage preserved in situ under conditions of gradual accumulation; ...

Tópico(s): Geological Studies and Exploration

1960 - Geological Society of America | Geological Society of America Bulletin

Artigo Revisado por pares

Ralph Gordon Johnson,

... 01, 1962 Mode of Formation of Marine Fossil Assemblages of the Pleistocene Millerton Formation of California RALPH ... GORDON JOHNSON; Mode of Formation of Marine Fossil Assemblages of the Pleistocene Millerton Formation of California. GSA ... Advanced Search Abstract The writer studied 13 fossil assemblages from the Pleistocene Millerton Formation of Tomales Bay, ... to infer the sources of the 13 fossil assemblages. Most of the Millerton fossil assemblages contain specimens exotic with respect to the majority ...

Tópico(s): Geology and Paleoclimatology Research

1962 - Geological Society of America | Geological Society of America Bulletin

Imagens Acesso aberto

35.3 mm x 45.1 mm. Photographer: Anonymous.

0000 - Gale Group | NCCO Photography

Artigo Revisado por pares

Margaret Grieve Mortimer,

A new spore assemblage of Siegenian age from Llanover, south Wales is described, and compared with an assemblage of Gedinnian age recently described by Chaloner and ... south Wales. These are compared with other new assemblages from the Faringdon borehole, the Brightling No. 1 ... be probably of Lower Devonian age. All five assemblages are dominated by relatively simple spore types. The Siegenian assemblage shows only a small increase in morphographical variety over the Gedinnian assemblage, but a considerable increase in the mean maximum ...

Tópico(s): Geological and Geophysical Studies

1967 - Elsevier BV | Review of Palaeobotany and Palynology

Imagens Acesso aberto

35.3 mm x 45.1 mm. Photographer: Anonymous.

0000 - Gale Group | NCCO Photography

Artigo

P. E. P. Norton,

... work the author defines a series of molluscan Assemblage Zones and attempts to interpret the ecological and ... local rather than regional significance. In the basal assemblage zone at Ludham (L.M. 1) and in zone L.M. 2 next above, the death-assemblages contain many Red Crag and Coralline Crag species, ... the Ludham Borehole belongs. The L.M. 1 assemblage suggests deposition in sublittoral marine waters shallower than 50 m; the L.M. 2 assemblage suggests deposition at approximately 15 m. In zone ... are very silty. The zone L.M. 5 assemblage indicates deposition in less than 8 m of ...

Tópico(s): Marine Biology and Ecology Research

1967 - Royal Society | Philosophical transactions of the Royal Society of London. Series B, Biological sciences

Imagens Acesso aberto

35.3 mm x 45.1 mm. Photographer: Anonymous.

0000 - Gale Group | NCCO Photography

Artigo Acesso aberto

Kenneth E. Lohman, George W. Andrews,

... in the section with a poorly preserved diatom assemblage. The Beaver Divide Conglomerate Member contains large blocks ... similar white limestone, some of which have an assemblage of diatoms the same as that of the ... Beaver Divide Conglomerate Member have virtually the same assemblages of nonmarine gastropods. A study of the local ... exposures of the Wagon Bed Formation. The diatom assemblage under consideration was originally deposited in the Wagon ... Oligocene in age. This represents the earliest known assemblage of nonmarine diatoms from North America. The diatom ...

Tópico(s): Diatoms and Algae Research

1968 - United States Government Publishing Office | USGS professional paper

Imagens Acesso aberto

35.3 mm x 45.1 mm. Photographer: Anonymous.

0000 - Gale Group | NCCO Photography

Artigo Revisado por pares

Nicklas G Pisias,

... eastern North Pacific allows the identification of four “assemblages” which can be related to the physical oceanography of the California Current. Two assemblages are associated with the southerly flowing California Current, ... the main stream of the current (California Current Assemblage) and the other with the offshore flow along northern California (Central Assemblage). The two other assemblages are associated with the subtropical region of the eastern North Pacific (Subtropical Assemblage) and one found mostly off the coast of ...

Tópico(s): Paleontology and Stratigraphy of Fossils

1978 - Cambridge University Press | Quaternary Research

Imagens Acesso aberto

35.3 mm x 45.1 mm. Photographer: Anonymous.

0000 - Gale Group | NCCO Photography

Artigo Acesso aberto

Yoshiaki Matsushima,

Six different types of shallow water molluscan assemblages have been distinguished from the embayment deposits accumulated during the maximum stage of the post-glacial Jomon Transgression (ca. 6, 500-5, 000y. ... P.) in the southern Kanto, central Japan. These assemblages are also recognized in the embayment deposits of ... P., the Crassostrea gigas-Anadara granosa-Batillaria zonalis assemblage and the Dosinella penicillata-Paphia undulata-Anadara broughtonii assemblage predominated in accordance with the development of muddy ...

Tópico(s): Isotope Analysis in Ecology

1978 - | The Quaternary Research (Daiyonki-Kenkyu)

Imagens Acesso aberto

35.3 mm x 45.1 mm. Photographer: Anonymous.

0000 - Gale Group | NCCO Photography

Artigo Acesso aberto

Jack A. Wolfe,

... the oldest possible age for the lowest plant assemblage is middle Eocene (Domengine) and that the youngest possible age for the highest Paleogene plant assemblage is middle Oligocene (Lincoln).Paleobotanical correlations indicate that the lowest plant assemblage is of late middle Eocene (early Ravenian) age, and the highest plant assemblage is of early Oligocene (Kummerian) age.A new provincial stage the Angoonian is proposed, based on assemblages from rocks in southeastern Alaska.The Angoonian is ... Oligocene (early Blakeley) age.Only one stratigraphically isolated assemblage from the Gulf of Alaska region has been ...

Tópico(s): Isotope Analysis in Ecology

1977 - United States Government Publishing Office | USGS professional paper

Imagens Acesso aberto

35.3 mm x 45.1 mm. Photographer: Anonymous.

0000 - Gale Group | NCCO Photography

Artigo Revisado por pares

J. W. H. Monger,

... Mesozoic age in the Canadian Cordillera form six assemblages, based mainly on lithological association and similar stratigraphy. From east to west these assemblages are: (1) Eastern assemblage, located along the Omineca Crystalline Belt and consisting ... and Permian ages; (3) Cache Creek – Bridge River assemblage of the Intermontane Bell, ranging from Lower Mississippian ... argillite, carbonate, basic volcanics, and ultramafics: (4) Stikine assemblage of northwestern and north-central British Columbia of ... carbonate and clastic succession: and (6) Sicker–Skolai assemblage of Vancouver Island and the Saint Elias Mountains ...

Tópico(s): Geochemistry and Geologic Mapping

1977 - NRC Research Press | Canadian Journal of Earth Sciences

Imagens Acesso aberto

35.3 mm x 45.1 mm. Photographer: Anonymous.

0000 - Gale Group | NCCO Photography

Artigo Revisado por pares

Bilal U. Haq, Gerrit Lohmann,

Biogeographic patterns of Early Cenozoic calcareous nannoplankton assemblages are delineated for the North and South Atlantic Ocean, Caribbean Sea, and Gulf of Mexico. Nannoplankton assemblages are defined byQ-mode Varimax Factor and Oblique ... latitudinal distribution through time allows recognition of those assemblages which can be used as environmental indicators. Comparison of the distributions of contemporaneous nannoplankton assemblages with the distribution of the appropriate environmental indicator ...

Tópico(s): Paleontology and Stratigraphy of Fossils

1976 - Elsevier BV | Marine Micropaleontology