Biostratigraphy and paleoecology of Upper Cretaceous (Campanian and Maestrichtian) foraminifera from the Upper Lambert, Northumberland, and Spray Formations, Gulf Islands, British Columbia, Canada

1979 ◽  
Vol 16 (12) ◽  
pp. 2263-2274 ◽  
Author(s):  
Alan McGugan
Keyword(s):  
Depositional Environment ◽  
Upper Cretaceous ◽  
Diversity Index ◽  
Generic Models ◽  
North Shore ◽  
The North ◽  
Shelf Slope ◽  
Gulf Islands ◽  
Local Geology ◽  
Upper Campanian

The Maestrichtian Bolivina incrassata fauna (upper part of Upper Lambert Formation) of Hornby Island (northern Comox Basin) is now recognized in the southern Nanaimo Basin on Gabriola and Galiano Islands. The Maestrichtian planktonic index species Globotruncana contusa occurs in the Upper Northumberlahd Formation of Mayne Island and Globotruncana calcarata (uppermost Campanian) occurs| in the Upper Northumberland Formation of Mayne Island and also in the Upper Lambert Formation at Manning Point on the north shore of Hornby Island (Comox Basin).Very abundant benthonic and planktonic foraminiferal assemblages from the Upper Campanian Lower Northumberland Formation of Mayne Island enable paleoecological interpretations to be made using the Fisher diversity index, triangular plots of Texturlariina/Rotaliina/Miliolina, calcareous/agglutinated ratios, planktonic/benthonic ratios, generic models, and associated microfossils and megafossils. Combined with local geology and stratigraphy a relatively shallow neritic depositional environment is proposed for the Northumberland Formation in agreement with Scott but not Sliter who proposed an Outer shelf/slope environment with depths of 300 m or more.

scholarly journals KEANEKARAGAMAN SERANGGA DALAM TANAH DI PANTAI ENDOK LOMBOK BARAT

2012 ◽  
Vol 7 (2) ◽  
Author(s):  
M. Liwa Ilhamdi
Keyword(s):  
Diversity Index ◽  
South Coast ◽  
Insect Diversity ◽  
The South ◽  
North Shore ◽  
The North ◽  
Tidal Area ◽  
Soil Insects ◽  
Lombok Island

Abstrak:  Penelitian ini bertujuan untuk  mengetahui keanekaragaman serangga dalam tanah  di pantai Endok Lombok Barat.  Sampel  serangga diambil dengan metode bor tanah dan dilanjutkan dengan metode berlesse tullgren. Pengambilan sampel dilakukan empat kali ulangan pada tiga stasiun yaitu stasiun I di sebelah utara pantai Endok, stasiun II bagian tengah, dan stasiun III di sebelah  selatan pantai Endok. Pada tiap stasiun terdiri dari 3 tempat yaitu area pasang surut, tengah dan zona pescapre. Selanjutnya data penelitian dianalisis dengan menggunakan indeks keanekaragaman Shannon Wiener. Hasil penelitian  nilai indeks keanekaragaman 1,27. Dari hasil penelitian di  atas dapat disimpulkan bahwa keanekaragaman serangga dalam tanah di pantai Endok Lombok Barat tergolong rendah.Kata-kata  kunci : Keanekaragaman, Serangga, Pantai Endok   Abstract: This research aims to determine the diversity of true soil insects at  coast of Endok Lombok island West. Sampling wasdone by the method of insect drill ground and continued with tullgren berlesse method. Samples were taken at three stations are first station on the north shore Endok, Station  II on the centre and Station III on the  south coast Endok. At each station is composed of 3 tidal area, central and pescapre zone. The data was analyzed using ShannonWiener diversity index. The result diversity index value1.27. From result of research above can be concluded that true soil insect diversity at coastal of Endok west Lombok island  is low category. Keywords : Diversity, Insect, Endok coastal

Impact of acidification on structural organization of phytoplankton community in the forest lakes of the north-western Russia

1996 ◽  
Vol 33 (4-5) ◽  
pp. 291-296 ◽  
Author(s):  
L. G. Korneva
Keyword(s):  
Phytoplankton Community ◽  
Diversity Index ◽  
Structural Characteristics ◽  
Total Biomass ◽  
North Shore ◽  
The North ◽  
Forest Lakes ◽  
Ph Range ◽  
North Western ◽  
The Rybinsk Reservoir

The response of the phytoplankton to different degree of pH was studied by the example of 7 shallow weakly mineralized forest lakes located in the Darwin National reserve on the north shore of the Rybinsk reservoir (north-western Russia). With a decrease of pH the number of phytoplankton species decreased especially among centric diatoms,blue-greens and Euglenophyta, total biomass of phytoplankton and its seasonal dispersion declined. Green algae, chrysomonades and cryptomonades biomass correlated negatively with pH but diatoms and blue-greens biomass were related positively to pH. The drop in pH produced a decrease of Shannon-Weaver diversity index, obtained from biomass and cell volume of algae, increase of Simpson index and algae size. The growth of phytoplankton did not correspond the total phosphorus. The necessary modifications to the structural characteristics of phytoplankton by the acidification came about in the pH range from 6 to 5.

scholarly journals Upper cretaceous magmatic suites of the Timok magmatic complex

2010 ◽  
pp. 13-22 ◽  
Author(s):  
Miodrag Banjesevic
Keyword(s):  
Depositional Environment ◽  
Upper Cretaceous ◽  
Volcanic Front ◽  
Magmatic Complex ◽  
Volcanic Material ◽  
Volcanic Processes ◽  
Different Types ◽  
Volcanic Facies ◽  
Volcanic Cycle ◽  
Upper Campanian

The Upper Cretaceous Timok Magmatic Complex (TMC) developed on a continental crust composed of different types of Proterozoic to Lower Cretaceous rocks. The TMC consists of the magmatic suites: Timok andesite (AT) - Turonian-Santonian, Metovnica epiclastite (EM) - Coniacian-Campanian, Osnic basaltic andesite (AO) and Jezevica andesite (AJ) - Santonian-Campanian, Valja Strz plutonite (PVS) - Campanian and Boljevac latite (LB). The sedimentary processes and volcanic activity of the TMC lasted nearly continuously throughout nearly the whole Late Cretaceous. The sedimentation lasted from the Albian to the Maastrichtian and the magmatism lasted for 10 million years, from the Upper Turonian to the Upper Campanian. The volcanic front migrated from East to West. The volcanic processes were characterized by the domination of extrusive volcanic facies, a great amount of volcanic material, a change in the depositional environment during the volcanic cycle, sharp facial transitions and a huge deposition of syn- and post-eruptive resedimented volcaniclastics.

Upper Campanian (Upper Cretaceous) ammonites from the Marshalltown formation-Mount Laurel boundary beds in Delaware

1997 ◽  
Vol 71 (1) ◽  
pp. 62-73 ◽  
Author(s):  
W. J. Kennedy ◽  
W. A. Cobban
Keyword(s):  
United States ◽  
Upper Cretaceous ◽  
The United States ◽  
Basal Part ◽  
The North ◽  
Index Species ◽  
Upper Campanian

New collections from the Marshalltown Formation and basal Mount Laurel Sand along the Chesapeake and Delaware Canal in Delaware clarify the ammonite dating of the interval. The Marshalltown Formation yields Pachydiscus (Pachydiscus) sp., Menuites portlocki (Sharpe, 1855) complexus (Hall and Meek, 1856), a subspecies restricted to the Baculites gregoryensis and Baculites scotti zones in the Western Interior of the United States, and Didymoceras binodosum (Kennedy and Cobban, 1993a) known only from the B. scotti zone of the Western Interior and correlatives in Arkansas and Texas. The basal part of the Mount Laurel Sand contains a complex assemblage preserved as phosphatic molds: Nostoceras (Nostoceras) monotuberculatum Kennedy and Cobban, 1993a, Nostoceras (N.) sp., Didymoceras platycostatum (Kennedy and Cobban, 1993b), D. stevensoni (Whitfield, 1877) (previously thought to be from the Marshalltown) and Exiteloceras jenneyi (Whitfield, 1877). The last two are index species of their eponymous zones in the Western Interior. This sequence is compatible with ammonites from the Wenonah Formation, which lies between the Marshalltown and Mount Laurel to the north and contains ammonites indicative of the Baculites scotti zone, and the fauna from higher in the Mount Laurel Sand, which includes elements of the Didymoceras cheyennense and Baculites compressus zones of the Western Interior sequence.

scholarly journals Iberoccitanemys atlanticum (Lapparent de Broin & Murelaga, 1996) n. comb.: new data on the diversity and paleobiogeographic distributions of the Campanian-Maastrichtian bothremydid turtles of Europe

2021 ◽  
Author(s):  
Adán PÉREZ-GARCÍA ◽  
Francisco ORTEGA ◽  
Xabier MURELAGA
Keyword(s):  
Fossil Record ◽  
Upper Cretaceous ◽  
Type Locality ◽  
The North ◽  
New Information ◽  
North Eastern ◽  
North Of Spain ◽  
Eastern Half ◽  
Upper Maastrichtian ◽  
Upper Campanian

Bothremydidae is the most abundant clade of turtles in the Campanian and Maastrichtian (Upper Cretaceous) fossil record of southwestern Europe. Several members of Foxemydina Gaffney, Tong & Meylan, 2006 are known in an area that includes Southern France and the North-Eastern half of Spain. The problematic ‘Polysternon’ atlanticum is the worst characterized, lacking a diagnosis that allows its specific validity to be confirmed, and whose generic attribution has been recognized as doubtful. Its presence was exclusively proposed in its type locality, the upper Campanian quarry of Laño, in Treviño County (Burgos Province, North of Spain). Despite the fact that knowledge about Bothremydidae has markedly increased after the description of ‘Polysternon’ atlanticum Lapparent de Broin & Murelaga, 1996, no new information about this species has been published since the 1990s. The analysis of abundant unpublished material of the bothremydid from Laño allows us to confirm the validity of this species. As a consequence of this study, it is not only identified in its type locality, but also in other Spanish regions and in the south of France. The diversity of Bothremydidae Baur, 1891 in the Upper Cretaceous of Europe is lower than previously considered. Thus, the species ‘Iberoccitanemys convenarum’ (Laurent, Tong & Claude, 2002), originally defined for the French record, and subsequently also identified in Spain, is identified here as a synonym of the species described in Laño. An emended diagnosis for the upper Campanian to upper Maastrichtian, Iberoccitanemys atlanticum (Lapparent de Broin & Murelaga, 1996) n. comb., is proposed.

Depositional Environment Drive as Overpressure Generation: Study Case in “Gap” Field, North West Java Basin

2020 ◽  
Author(s):  
A., C. Prasetyo
Keyword(s):  
Clay Mineral ◽  
Depositional Environment ◽  
Mineral Content ◽  
Hydrocarbon Generation ◽  
Well Test ◽  
Burial History ◽  
The South ◽  
North West ◽  
The North ◽  
Geological Processes

Overpressure existence represents a geological hazard; therefore, an accurate pore pressure prediction is critical for well planning and drilling procedures, etc. Overpressure is a geological phenomenon usually generated by two mechanisms, loading (disequilibrium compaction) and unloading mechanisms (diagenesis and hydrocarbon generation) and they are all geological processes. This research was conducted based on analytical and descriptive methods integrated with well data including wireline log, laboratory test and well test data. This research was conducted based on quantitative estimate of pore pressures using the Eaton Method. The stages are determining shale intervals with GR logs, calculating vertical stress/overburden stress values, determining normal compaction trends, making cross plots of sonic logs against density logs, calculating geothermal gradients, analyzing hydrocarbon maturity, and calculating sedimentation rates with burial history. The research conducted an analysis method on the distribution of clay mineral composition to determine depositional environment and its relationship to overpressure. The wells include GAP-01, GAP-02, GAP-03, and GAP-04 which has an overpressure zone range at depth 8501-10988 ft. The pressure value within the 4 wells has a range between 4358-7451 Psi. Overpressure mechanism in the GAP field is caused by non-loading mechanism (clay mineral diagenesis and hydrocarbon maturation). Overpressure distribution is controlled by its stratigraphy. Therefore, it is possible overpressure is spread quite broadly, especially in the low morphology of the “GAP” Field. This relates to the delta depositional environment with thick shale. Based on clay minerals distribution, the northern part (GAP 02 & 03) has more clay mineral content compared to the south and this can be interpreted increasingly towards sea (low energy regime) and facies turned into pro-delta. Overpressure might be found shallower in the north than the south due to higher clay mineral content present to the north.

On Riccia marginata and related species (Ricciaceae, Marchantiophyta)

2012 ◽  
Vol 46 ◽  
pp. 298-305 ◽  
Author(s):  
A. D. Potemkin ◽  
T. Ahti
Keyword(s):  
Related Species ◽  
Lake Ladoga ◽  
Leningrad Region ◽  
Sem Images ◽  
North Shore ◽  
The North ◽  
Molecular Studies ◽  
The Future ◽  
The Town

Riccia marginata Lindb. was described by S. O. Lindberg (1877) from the outskirts of the town of Sortavala near the north shore of Lake Ladoga, Republic of Karelia, Russia. The species has been forgotten in most recent liverwort accounts of Europe, including Russia. Lectotypification of R. marginata is provided. R. marginata shares most characters with R. beyrichiana Hampe ex Lehm. It differs from “typical” plants of R. beyrichiana in having smaller spores, with ± distinctly finely areolate to roughly papillose proximal surfaces and a narrower and shorter thallus, as well as in scarcity or absence of marginal hairs. It may represent continental populations of the suboceanic-submediterranean R. beyrichiana, known in Russia from the Leningrad Region and Karelia only. The variability of spore surfaces in R. beyrichiana is discussed and illustrated by SEM images. A comparison with the spores of R. bifurca Hoffm. is provided. The question how distinct R. marginata is from R. beyrichiana needs to be clarified by molecular studies in the future, when adequate material is available. R. marginata is for the time being, provisionally, included in R. beyrichiana.

Conflict, Population Movement, and Microscale Social Networks in Northern Iroquoian Archaeology

2021 ◽  
Vol 86 (2) ◽  
pp. 350-367
Author(s):  
Jennifer Birch ◽  
John P. Hart
Keyword(s):  
Social Networks ◽  
Sixteenth Century ◽  
Lake Ontario ◽  
Population Movement ◽  
Network Ties ◽  
The West ◽  
Local Networks ◽  
North Shore ◽  
The North ◽  
Specific Sequences

We employ social network analysis of collar decoration on Iroquoian vessels to conduct a multiscalar analysis of signaling practices among ancestral Huron-Wendat communities on the north shore of Lake Ontario. Our analysis focuses on the microscale of the West Duffins Creek community relocation sequence as well as the mesoscale, incorporating several populations to the west. The data demonstrate that network ties were stronger among populations in adjacent drainages as opposed to within drainage-specific sequences, providing evidence for west-to-east population movement, especially as conflict between Wendat and Haudenosaunee populations escalated in the sixteenth century. These results suggest that although coalescence may have initially involved the incorporation of peoples from microscale (local) networks, populations originating among wider mesoscale (subregional) networks contributed to later coalescent communities. These findings challenge previous models of village relocation and settlement aggregation that oversimplified these processes.

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