Abstract: The West Siberian Bazhenov Petroleum System In Situ": Geological Evolution and Generation-Accumulation Efficiency"

AAPG Bulletin ◽  
1999 ◽  
Vol 83 ◽  
Author(s):  
LOPATIN, NIKLOLAY, and TAMARA EMETS
Keyword(s):  
Petroleum System ◽  
The West ◽  
Geological Evolution ◽  
Accumulation Efficiency

scholarly journals In Situ Geochemical Compositions of the Minerals in Basaltic Rocks from the West Philippine Basin: Constraints on Source Lithology and Magmatic Processes

Lithosphere ◽  
2020 ◽  
Vol 2020 (1) ◽  
pp. 1-24
Author(s):  
Long Yuan ◽  
Quanshu Yan ◽  
Yanguang Liu ◽  
Shiying Wu ◽  
Ruirui Wang ◽  
...  
Keyword(s):  
Mantle Plume ◽  
Spreading Center ◽  
Minor Amount ◽  
The West ◽  
Basaltic Rocks ◽  
West Philippine Basin ◽  
Geological Evolution ◽  
Magmatic Processes ◽  
Back Arc

Abstract Since the early Cenozoic, the West Philippine Basin (WPB) and the whole Philippine Sea Plate (PSP) has undergone a complex geological evolution. In this study, we presented K-Ar ages, in situ trace element, and major element compositions of minerals of basalts collected from the Benham Rise and the Central Basin Fault (CBF) in the WPB, to constrain their magmatic process and regional geological evolution. Olivine phenocrysts and microlites in the alkali basalts (20.9 Ma) from the Benham Rise have forsterite (Fo) contents of 56.90%–76.10% and 53.13%-66.41%, respectively. The clinopyroxenes in the tholeiites (29.1 Ma) from the CBF is predominantly diopside and augite, and it is depleted in light rare earth elements (LREEs) (LaN/YbN=0.13–3.40) and large-ion lithophile elements (LILEs). The plagioclases in the basalts from both of the Benham Rise and the CBF are predominantly labradorite and andesine, with a minor amount of bytownite, and it is enriched in LREEs, Ba, Sr, and Pb and exhibits strong positive Eu anomalies. However, there exist obvious differences in plagioclase compositions between these two tectonic sites. The source lithology of the Benham Rise basaltic rocks could be garnet pyroxenite, and yet that of the CBF could be spinel-lherzolite. The calculated mantle potential temperature beneath the Benham Rise is 1439°C–1473°C, which is significantly higher than that beneath the CBF (1345°C–1381°C), suggesting there existed thermal anomaly beneath the Rise during basaltic magmatism. This study also calculated the temperature and pressure of the clinopyroxenes and plagioclases, which have been used to indicate magmatic processes. Finally, we suggest that the Benham Rise basaltic rocks may be related to a mantle plume (e.g., the Oki-Daito mantle plume), and the CBF was once located in a back-arc spreading center behind an active subduction zone. The extinction of the Oki-Daito mantle plume activity might be at about 20.9 Ma, and cessation of the back-arc spreading of WPB was at about 29.1 Ma or younger.

Five tombs at Knossos

1963 ◽  
Vol 58 ◽  
pp. 30-43 ◽  
Author(s):  
J. N. Coldstream
Keyword(s):  
Good Condition ◽  
Good Deal ◽  
Lower Edge ◽  
Water Pipe ◽  
The West ◽  
Light In August ◽  
South West ◽  
History Of ◽  
The Temple

On the east slope of Lower Gypsades hill, about 100 metres west of the Temple Tomb, a chamber tomb came to light in August 1958, when a cutting for a new water pipe was driven through the area (A in Plate 9 a). In the course of this operation, part of a plain larnax (iii) was sliced off, and much earth removed from the west end of the collapsed chamber: at no point, however, had the municipal workmen penetrated to the tomb floor.The chamber was approached by a sloping dromos (Plate 9 a: length 2·80 metres; max. width 1 metre), roughly cut into the natural kouskouras rock: its walls were approximately perpendicular. Although the gradient varied a good deal, there was no suggestion of a stairway.The blocking wall was found in good condition. Of especial interest were the numerous fragments of larnakes that had been built into its fabric: some of them could be recognized as belonging to each of the three fragmentary larnakes (i, ii, v) whose scattered pieces were found below and around the two undisturbed burials in the chamber (iii, iv). We may thus distinguish two periods in the history of the tomb: larnakes i, ii, and v were evidently smashed up in order to make room for iv and iii, which must have been deposited in that order. The debris of v was found under iv, with a few adult bones in its wreckage. Part of i lay on the floor near the south-west corner, where two plain vases (2, 3) were found in situ, hence, also, came most of the fragments of the fine L.M. IIIA 2 stirrup vase (1), although its other pieces were scattered all over the floor of the tomb. This small group of offerings may belong to the disturbed adult skeleton, whose skull lay up against the lower edge of iii. Curiously, some fragments of i and ii were also found above the broken lid of iv (Plate 9 b): perhaps the lid of the later larnax was accidentally smashed at the time of the funeral, in which case the debris from earlier burials could have been piled up above it, as a rough and ready means of protection.

Anti-contiguity Crosslinguistically

2020 ◽  
pp. 100-122
Author(s):  
Jason Kandybowicz
Keyword(s):  
West African ◽  
Linguistic Context ◽  
The West ◽  
African Languages

This chapter concludes the book by considering Anti-contiguity in a cross-linguistic context. It is shown that the proposal can be successfully applied to derive asymmetries in wh- in-situ distribution beyond the West African languages considered in Chapters 2–4. The chapter focuses on thirteen languages from diverse language families (Romance, Bantu, and Indo-Aryan, among others) and considers the implications of data from these languages for the final formulation of the Anti-contiguity condition. On the basis of these considerations, the Anti-contiguity constraint is parameterized. Among the languages considered against the backdrop of the Anti-contiguity proposal in this chapter are French; Spanish; Catalan; Zulu; Bàsàá; Duala; Shona; Lubukusu; Kiitharaka; Hindi-Urdu; Bangla; Iraqi Arabic; and Malayalam.

scholarly journals The vertical distribution of biomass burning pollution over tropical South America from aircraft in situ measurements during SAMBBA

2019 ◽  
Vol 19 (9) ◽  
pp. 5771-5790 ◽  
Author(s):  
Eoghan Darbyshire ◽  
William T. Morgan ◽  
James D. Allan ◽  
Dantong Liu ◽  
Michael J. Flynn ◽  
...  
Keyword(s):  
Air Quality ◽  
South America ◽  
Vertical Distribution ◽  
Biomass Burning ◽  
Mixing Layer ◽  
Free Troposphere ◽  
The West ◽  
The Vertical Distribution ◽  
Tropical South America

Abstract. We examine processes driving the vertical distribution of biomass burning pollution following an integrated analysis of over 200 pollutant and meteorological profiles measured in situ during the South AMerican Biomass Burning Analysis (SAMBBA) field experiment. This study will aid future work examining the impact of biomass burning on weather, climate and air quality. During the dry season there were significant contrasts in the composition and vertical distribution of haze between western and eastern regions of tropical South America. Owing to an active or residual convective mixing layer, the aerosol abundance was similar from the surface to ∼1.5 km in the west and ∼3 km in the east. Black carbon mass loadings were double as much in the east (1.7 µg m−3) than the west (0.85 µg m−3), but aerosol scattering coefficients at 550 nm were similar (∼120 Mm−1), as too were CO near-surface concentrations (310–340 ppb). We attribute these contrasts to the more flaming combustion of Cerrado fires in the east and more smouldering combustion of deforestation and pasture fires in the west. Horizontal wind shear was important in inhibiting mixed layer growth and plume rise, in addition to advecting pollutants from the Cerrado regions into the remote tropical forest of central Amazonia. Thin layers above the mixing layer indicate the roles of both plume injection and shallow moist convection in delivering pollution to the lower free troposphere. However, detrainment of large smoke plumes into the upper free troposphere was very infrequently observed. Our results reiterate that thermodynamics control the pollutant vertical distribution and thus point to the need for correct model representation so that the spatial distribution and vertical structure of biomass burning smoke is captured. We observed an increase of aerosol abundance relative to CO with altitude both in the background haze and plume enhancement ratios. It is unlikely associated with thermodynamic partitioning, aerosol deposition or local non-fire sources. We speculate it may be linked to long-range transport from West Africa or fire combustion efficiency coupled to plume injection height. Further enquiry is required to explain the phenomenon and explore impacts on regional climate and air quality.

The Genesee Connection: The Origins of Iroquois Culture in West-Central New York

1986 ◽  
Vol 7 (1) ◽  
pp. 15-44
Author(s):  
Mary Ann Palmer Niemczycki
Keyword(s):  
New York ◽  
Diagnostic Criteria ◽  
Current Concept ◽  
The West ◽  
Diagnostic Significance ◽  
West Central ◽  
Central New York

The Genesee Valley has long been recognized as a center of Iroquois development, but the connection between Owasco sites in the Genesee and Iroquois sequences in the adjacent regions has never been adequately demonstrated. Attempts to identify transitional Owasco-Iroquois sites in this region have been hampered by the use of diagnostic criteria based on data from eastern New York. This article examines ceramic patterns in the Genesee and establishes a regional cultural sequence based on ceramic criteria which have local diagnostic significance. This sequence reveals the transition from Owasco to Iroquois culture begins in the Genesee with a sudden influx of Ontario Iroquois ceramic traits from the west ca. 1250 A.D. This Owasco-Ontario Iroquois connection in the Genesee negates certain assumptions regarding Iroquois origins and alters our current concept of in situ development.

Large scale high resolution modelling of the West African rivers and aquifers

2020 ◽  
Author(s):  
Alban Depeyre ◽  
Jean-Martial Cohard ◽  
Basile Hector ◽  
Reed Maxwell ◽  
Thierry Pellarin
Keyword(s):  
Water Resources ◽  
West Africa ◽  
Large Scale ◽  
River Flow ◽  
Hydrological Cycle ◽  
Soil Parameters ◽  
Global Changes ◽  
The West ◽  
Main Challenge

<p>West Africa has been classified as one of the most vulnerable regions in the world for water resources to face global changes, both climatic and demographic. The population is expected to double by 2050 leading to increased pressure on the use of water resources. In this context, it is necessary to understand the dynamics of major African hydrosystems as large rivers (Niger river, Senegal river...) and transboundary aquifers in order to predict the fate of water resources for the next decades. The ParFlow-CLM physical-based model was chosen for its ability to simulate surface water and groundwater dynamics in a coupled manner. This type of modelling makes it possible to represent the main hydrological processes observed over the whole West Africa region. It operates at a relatively fine spatial resolution (1 km²). The main challenge is to determine the hydrodynamic parameters of the soil for the entire region and on a 100 m thickness (i.e. 3.5 million pixels times 11 layers).</p><p>As a first step, the model was implemented on two catchments monitored by the AMMA-CATCH observatory. These two watersheds are representative of the major and contrasted processes found in WA : being respectively representative of Sudanian and Sahelian climates. In order to assess the relevance of the regional databases (SoilGrids and GLHYMPS), simulations were carried out with original and adjusted (based on observations) soil parameters and results were evaluated with local measurements. It appears that the deep weathered lithology is not considered in databases for most of hard-rock areas in intertropical areas with no tectonic uplift. Aquifer thicknesses, permeabilities and porosities have to be significantly enhanced for the model to represent the correct flow paths. Furthermore, in the Sahel where most of the annual precipitation falls during a dozen events only, a crust layer (consistent with observations) has been added to represent the large runoff coefficients which lead to the early season floods.</p><p>In a second step, the model was implemented at the West Africa scale using the adjusted soil parameters. These parameters were obtained using a simple linear law that have been applied uniformly over the entire domain and a mask over a part of the Sahel representative of the crusting zones. Results will be compared with both remotely sensed and in situ data : GRACE provides water stock variations at a very large scale, MERRA and ERA reanalysis provide evapotranspiration data. Altimeters and in situ measurements provide river flow data. In the near future the launch of the SWOT satellite will bring new observations to complete the current one. The evaluation of the different compartments of the hydrological cycle should reveal spatial discrepancies in the model's ability to represent processes, highlighting the points on which further work should focus.</p>

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