scholarly journals Peculiar features of correlation between petrophysical signatures of rocks and distribution of geophysical heterogeneities in the Monchegorsk ore area (Kola Peninsula, northeastern Baltic Shield)

2021 ◽  
Vol 43 (4) ◽  
pp. 176-198
Author(s):  
V.T. Filatova
Keyword(s):  
Physical Properties ◽  
Physical Parameters ◽  
Near Surface ◽  
Petrophysical Parameters ◽  
Basement Rocks ◽  
Structural Plan ◽  
Weakly Magnetic ◽  
Host Rocks ◽  
State Of The Environment ◽  
Geophysical Anomalies

The current article presents stratified data on physical properties of rocks and ores from the Monchegorsk ore area (Kola region). The constructed petrodensity and petromagnetic maps reflect peculiar features of changes in petrophysical parameters of both Paleoproterozoic intrusive rocks and host rocks at the Archean basement of the area. To assess the complementarity degree of physical properties of the rocks and geophysical fields, we additionally analyzed the structure of geophysical anomalies (Δg, ΔZ) in the study area. It allowed constructing a distribution scheme for geophysical heterogeneity in the area and assessing their nature. The conducted studies showed that nickel-bearing and potentially nickel-bearing intrusions in the Monchegorsk ore area were highly dense, but composed of weakly magnetic rocks. Layering of the gabbro-labradorite massif of the Main Ridge is reflected in petrophysical parameters, i. e. endocontact gabbro and gabbronorite show an increased density and magnetic susceptibility compared to leucocratic gabbro and labradorite in the core of the intrusion. Thus, petrophysical data indicate a general increase in the basicity of the rocks towards the bottom of the intrusion. The discrepancy between intense geophysical anomalies and physical parameters of near-surface rocks of the block adjacent to the gabbro-labradorite massif of the Main Ridge in the southeast was revealed. This fact indicates a layer of dense rocks under the supracrustal basement rocks (a complex of gneisses and amphibolized volcanic-sedimentary rocks) and rocks of the Imandra-Varzuga structure. This layer can be composed of potentially nickel-bearing rocks of the Imandra complex, including intrusions of the clinopyroxene-wehrlite formation series exposed in some areas. According to the configuration pattern of the identified axes of local magnetic anomalies, the Archean blocks are considered isolated areas given the uniform pattern they create, i. e. Belomorian — isometric structures, Kola — linearly extended. Therefore, during transformation of the structural plan in the Paleoproterozoic, the Archean blocks gave differentiated responses to the emerging stress-strain state of the environment and were subject to heterogeneous deformations. The performed work, including integrated results of petrophysical studies with the analysis of the structure of geophysical anomalies in the ore region, is relevant in substantiating a strategy for prospecting for new ore occurrences and patterns of their localization, as well as for developing criteria for predicting industrial ores in the region. At the same time, the studies carried out make it possible to answer questions related to the reconstruction of the geodynamic settings that took place during the formation of the region’s crust.

scholarly journals Analysis of the Physical Properties of Seeds of Selected Viburnum Species for the Needs of Seed Sorting Operations

Processes ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 711
Author(s):  
Zdzisław Kaliniewicz ◽  
Dariusz J. Choszcz
Keyword(s):  
Physical Properties ◽  
Ornamental Plants ◽  
Seed Mass ◽  
Terminal Velocity ◽  
Landscape Design ◽  
Physical Parameters ◽  
Regression Analyses ◽  
Uniform Size ◽  
Size Fractions ◽  
Physical Attributes

Viburnum is a genus of colorful and ornamental plants popular in landscape design on account of their high esthetic appeal. The physical properties of viburnum seeds have not been investigated in the literature to date. Therefore, the aim of this study was to characterize the seeds of selected Viburnum species and to search for potential relationships between their physical attributes for the needs of seed sorting operations. The basic physical parameters of the seeds of six Viburnum species were measured, and the relationships between these attributes were determined in correlation and regression analyses. The average values of the evaluated parameters were determined in the following range: terminal velocity—from 5.6 to 7.9 m s−1, thickness—from 1.39 to 1.87 mm, width—from 3.59 to 6.33 mm, length—from 5.58 to 7.44 mm, angle of external friction—from 36.7 to 43.8°, mass—from 16.7 to 35.0 mg. The seeds of V. dasyanthum, V. lentago and V. sargentii should be sorted in air separators, and the seeds of V. lantana and V. opulus should be processed with the use of mesh screens with round apertures to obtain uniform size fractions. The seeds of V. rhytodophyllum cannot be effectively sorted into batches with uniform seed mass, but they can be separated into groups with similar dimensions.

Physical Properties of Saltstone: Physical Properties of Saltstone: A Savannah River Plant Waste Form

1984 ◽  
Vol 44 ◽  
Author(s):  
Christine A. Langton
Keyword(s):  
Compressive Strength ◽  
Physical Properties ◽  
Field Tests ◽  
Waste Form ◽  
Savannah River ◽  
X Ray Diffraction ◽  
Near Surface ◽  
Leach Rate ◽  
Savannah River Plant ◽  
Water To Cement Ratio

AbstractA cement-based waste form, “saltstone,” has been designed for disposal of Savannah River Plant low-level radioactive salt waste. Laboratory and field tests indicate that this stabilization process greatly reduces the mobility of all of the waste constituents in the surface and near-surface environment. Bulk properties of this material have been tailored with respect to salt leach rate, permeability, and compressive strength. Microstructure and mineralogy were characterized by SEM and x-ray diffraction analyses.Compressive strength was found to increase as the water to cement ratio decreased. Porosity and mean pore size increased with increasing water to cement ratios. Bulk diffusivities of the various ions dissolved in the pore solutions were also found to increase as water to cement ratios increased.

Physical properties and spatial distribution of the sea ice surface layer (SSL/snow) during the autumn phase of the MOSAiC expedition

2021 ◽  
Author(s):  
Ruzica Dadic ◽  
Martin Schneebeli ◽  
Henna-Reeta Hannula ◽  
Amy Macfarlane ◽  
Roberta Pirazzini
Keyword(s):  
Surface Layer ◽  
Spatial Distribution ◽  
Sea Ice ◽  
Physical Properties ◽  
Surface Scattering ◽  
Climate Feedback ◽  
Energy Fluxes ◽  
Scattering Layer ◽  
Near Surface ◽  
Ice Surface

<p>Snow cover dominates the thermal and optical properties of sea ice and the energy fluxes between the ocean and the atmosphere, yet data on the physical properties of snow and its effects on sea ice are limited. This lack of data leads to two significant problems: 1) significant biases in model representations of the sea ice cover and the processes that drive it, and 2) large uncertainties in how sea ice influences the global energy budget and the coupling of climate feedback. The  MOSAiC research initiative enabled the most extensive data collection of snow and surface scattering layer (SSL) properties over sea ice to date. During leg 5 of the MOSAiC expedition, we collected multi-scale (microscale to 100-m scale) measurements of the surface layer (snow/SSL) over first year ice (FYI) and MYI on a daily basis. The ultimate goal of our measurements is to determine the spatial distribution of physical properties of the surface layer. During leg 5 of the MOSAiC expedition, that surface layer changed from the  surface scattering layer (SSL),   characteristic for the melt season, to an early autumn snow pack. Here,  we will present data showing both a) the physical properties and the spatial distribution of the SSL during the late melt season and b) the transition of the sea ice surface from the SSL to the fresh autumn snowpack. The structural properties of this transition period are poorly documented, and this season is critical  for the initialization of sea ice and snow models. Furthermore, these data are crucial to interpret simultaneous observations of surface energy fluxes, surface optical and remote sensing data (microwave signals in particular), near-surface biochemical activity, and to understand the sea ice  processes that occur as the sea ice transitions from melting to freezing.</p>

Evaluating the role of soil physical properties on simulated land-atmosphere interactions over South Africa using coupled atmosphere-hydrological modeling

2021 ◽  
Author(s):  
Zhenyu Zhang ◽  
Patrick Laux ◽  
Joël Arnault ◽  
Jianhui Wei ◽  
Jussi Baade ◽  
...  
Keyword(s):  
South Africa ◽  
Physical Properties ◽  
Land Degradation ◽  
Land Surface ◽  
Soil Physical Properties ◽  
Near Surface ◽  
Soil Database ◽  
Global Soil ◽  
The Impact

<p>Land degradation with its direct impact on vegetation, surface soil layers and land surface albedo, has great relevance with the climate system. Assessing the climatic and ecological effects induced by land degradation requires a precise understanding of the interaction between the land surface and atmosphere. In coupled land-atmosphere modeling, the low boundary conditions impact the thermal and hydraulic exchanges at the land surface, therefore regulates the overlying atmosphere by land-atmosphere feedback processes. However, those land-atmosphere interactions are not convincingly represented in coupled land-atmosphere modeling applications. It is partly due to an approximate representation of hydrological processes in land surface modeling. Another source of uncertainties relates to the generalization of soil physical properties in the modeling system. This study focuses on the role of the prescribed physical properties of soil in high-resolution land surface-atmosphere simulations over South Africa. The model used here is the hydrologically-enhanced Weather Research and Forecasting (WRF-Hydro) model. Four commonly used global soil datasets obtained from UN Food and Agriculture Organization (FAO) soil database, Harmonized World Soil Database (HWSD), Global Soil Dataset for Earth System Model (GSDE), and SoilGrids dataset, are incorporated within the WRF-Hydro experiments for investigating the impact of soil information on land-atmosphere interactions. The simulation results of near-surface temperature, skin temperature, and surface energy fluxes are presented and compared to observational-based reference dataset. It is found that simulated soil moisture is largely influenced by soil texture features, which affects its feedback to the atmosphere.</p>

scholarly journals Understanding Type II Supernovae

2005 ◽  
Vol 192 ◽  
pp. 275-280 ◽  
Author(s):  
L. Zampieri ◽  
M. Ramina ◽  
A. Pastorello
Keyword(s):  
Physical Properties ◽  
Large Range ◽  
Simultaneous Analysis ◽  
Light Curves ◽  
Physical Parameters ◽  
Expansion Velocity ◽  
Type Ii ◽  
Strong Correlations ◽  
Systematic Analysis ◽  
Robust Estimates

SummaryWe present the results of a systematic analysis of a group of Type II plateau supernovae that span a large range in luminosities, from faint objects like SN 1997D and 1999br to very luminous events like SN 1992am. The physical properties of the supernovae appear to be related to the plateau luminosity or the expansion velocity. The simultaneous analysis of the observed light curves, line velocities and continuum temperatures leads us to robust estimates of the physical parameters of the ejected envelope. We find strong correlations among several parameters. The implications of these results regarding the nature of the progenitor, the central remnant and the Ni yield are also addressed.

scholarly journals Study on the Water-Physical Properties of the Cement-Plaster Bonded Rock-Like Materials

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Yong Zhang ◽  
Zhiguo Cao ◽  
Xiaomeng Shi
Keyword(s):  
Physical Properties ◽  
Physical Model ◽  
Coupling Model ◽  
Model Tests ◽  
Physical Parameters ◽  
Test Results ◽  
Physical Model Tests ◽  
Fluid Coupling ◽  
Softening Coefficient ◽  
Solid Fluid Coupling

The cement-plaster bonded rock-like material is one of the most commonly used materials to simulate different rocks in physical model tests. However, the applicability of this material in solid-fluid coupling model tests is not clear because there are few research studies on the water-physical properties of this material and its similarity to the actual rock is uncertain. This paper presents a systemic experimental study on the water-physical properties of the cement-plaster bonded rock-like materials. The parameters of rock-like materials, including water absorption, softening coefficient, and permeability coefficient, were compared with those of actual rocks to analyse the applicability of such material. Then, the influence of proportion on the water-physical properties of this material was discussed. By multiple regression analysis of the test results, empirical equations between the water-physical parameters and proportions were proposed. The equations can be used to estimate the water-physical properties of cement-plaster bonded rock-like materials with specific proportion and thus to select suitable materials in the solid-fluid coupling physical model tests.

Cropping system influences on soil physical properties in the Great Plains

2006 ◽  
Vol 21 (1) ◽  
pp. 15-25 ◽  
Author(s):  
J.L. Pikul ◽  
R.C. Schwartz ◽  
J.G. Benjamin ◽  
R.L. Baumhardt ◽  
S. Merrill
Keyword(s):  
Physical Properties ◽  
Cropping Systems ◽  
Aggregate Size ◽  
Cropping System ◽  
Soil Physical Properties ◽  
Water Infiltration ◽  
Soil Conditions ◽  
System Effect ◽  
Near Surface ◽  
Infiltration Rates

AbstractAgricultural systems produce both detrimental and beneficial effects on soil quality (SQ). We compared soil physical properties of long-term conventional (CON) and alternative (ALT) cropping systems near Akron, Colorado (CO); Brookings, South Dakota (SD); Bushland, Texas (TX); Fargo, North Dakota (ND); Mandan (ND); Mead, Nebraska (NE); Sidney, Montana (MT); and Swift Current, Saskatchewan (SK), Canada. Objectives were to quantify the changes in soil physical attributes in cropping systems and assess the potential of individual soil attributes as sensitive indicators of change in SQ. Soil samples were collected three times per year from each treatment at each site for one rotation cycle (4 years at Brookings and Mead). Water infiltration rates were measured. Soil bulk density (BD) and gravimetric water were measured at 0–7.5, 7.5–15, and 15–30 cm depth increments and water-filled pore space ratio (WFPS) was calculated. At six locations, a rotary sieve was used to separate soil (top 5 cm) into six aggregate size groups and calculate mean weight diameter (MWD) of dry aggregates. Under the CON system at Brookings, dry aggregates (>19 mm) abraded into the smallest size class (<0.4 mm) on sieving. In contrast, the large aggregates from the ALT system abraded into size classes between 2 and 6 mm. Dry aggregate size distribution (DASD) shows promise as an indicator of SQ related to susceptibility of soil to wind erosion. Aggregates from CON were least stable in water. Soil C was greater under ALT than CON for both Brookings and Mead. At other locations, MWD of aggregates under continuous crop or no tillage (ALT systems) was greater than MWD under CON. There was no crop system effect on water infiltration rates for locations having the same tillage within cropping system. Tillage resulted in increased, decreased, or unchanged near-surface BD. Because there was significant temporal variation in water infiltration, MWD, and BD, conclusions based on a single point-in-time observation should be avoided. Elevated WFPS at Fargo, Brookings, and Mead may have resulted in anaerobic soil conditions during a portion of the year. Repeated measurements of WFPS or DASD revealed important temporal characteristics of SQ that could be used to judge soil condition as affected by management.

scholarly journals First-Principles Calculations of High-Pressure Physical Properties of Ti0.5Ta0.5 Alloy

Symmetry ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 796
Author(s):  
Fang Yu ◽  
Yu Liu
Keyword(s):  
High Pressure ◽  
Physical Properties ◽  
First Principles ◽  
Theoretical Study ◽  
Applied Pressure ◽  
Lattice Parameter ◽  
Physical Parameters ◽  
First Principles Calculations ◽  
Analysis Method ◽  
Metallic Bond

In this paper, an in-depth theoretical study on some physical properties of Ti0.5Ta0.5 alloy with systematic symmetry under high pressure is conducted via first-principles calculations, and relevant physical parameters are calculated. The results demonstrate that the calculated parameters, including lattice parameter, elastic constants, and elastic moduli, fit well with available theoretical and experimental data when the Ti0.5Ta0.5 alloy is under T = 0 and P = 0 , indicating that the theoretical analysis method can effectively predict the physical properties of the Ti0.5Ta0.5 alloy. The microstructure and macroscopic physical properties of the alloy cannot be destroyed as the applied pressure ranges from 0 to 50GPa, but the phase transition of crystal structure may occur in the Ti0.5Ta0.5 alloy if the applied pressure continues to increase according to the TDOS curves and charge density diagram. The value of Young’s and shear modulus is maximized at P = 25   GPa . The anisotropy factors A ( 100 ) [ 001 ] and A ( 110 ) [ 001 ] are equal to 1, suggesting the Ti0.5Ta0.5 alloy is an isotropic material at 28 GPa, and the metallic bond is strengthened under high pressure. The present results provide helpful insights into the physical properties of Ti0.5Ta0.5 alloy.

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