Geophysical tools to study the near-surface distribution of the tailings in the Smaltjärnen repository, south-central Sweden; a feasibility study

Abstract This study examines the evolution of soil moisture, evapotranspiration, vegetation, and atmospheric conditions during an unusual flash drought–flash recovery sequence that occurred across the south-central United States during 2015. This event was characterized by a period of rapid drought intensification (flash drought) during late summer that was terminated by heavy rainfall at the end of October that eliminated the extreme drought conditions over a 2-week period (flash recovery). A detailed analysis was performed using time series of environmental variables derived from meteorological, remote sensing, and land surface modeling datasets. Though the analysis revealed a similar progression of cascading effects in each region, characteristics of the flash drought such as its onset time, rate of intensification, and vegetation impacts differed between regions due to variations in the antecedent conditions and the atmospheric anomalies during its growth. Overall, flash drought signals initially appeared in the near-surface soil moisture, followed closely by reductions in evapotranspiration. Total column soil moisture deficits took longer to develop, especially in the western part of the region where heavy rainfall during the spring and early summer led to large moisture surpluses. Large differences were noted in how land surface models in the North American Land Data Assimilation System depicted soil moisture evolution during the flash drought; however, the models were more similar in their assessment of conditions during the flash recovery period. This study illustrates the need to use multiple datasets to track the evolution and impacts of rapidly evolving flash drought and flash recovery events.

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Luminescence studies on neotectonic events in south-central Kumaun Himalaya — a feasibility study

Quaternary Science Reviews ◽

10.1016/0277-3791(94)90083-3 ◽

1994 ◽

Vol 13 (5-7) ◽

pp. 595-600 ◽

Cited By ~ 35

Author(s):

A.K. Singhvi ◽

D. Banerjee ◽

K. Pande ◽

V. Gogte ◽

K.S. Valdiya

Keyword(s):

Feasibility Study ◽

Kumaun Himalaya ◽

South Central

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Hydroacoustical Survey of Near-Surface Distribution, Abundance and Biomass of Small Pelagic Fish in the Gulf of California

Pacific Science ◽

10.2984/66.3.5 ◽

2012 ◽

Vol 66 (3) ◽

pp. 311-326 ◽

Cited By ~ 3

Author(s):

José Francisco Domínguez-Contreras ◽

Carlos J. Robinson ◽

Jaime Gómez-Gutiérrez

Keyword(s):

Gulf Of California ◽

Pelagic Fish ◽

Small Pelagic Fish ◽

Surface Distribution ◽

Near Surface

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Crop Diversity Effects on Near-Surface Soil Condition under Dryland Agriculture

Applied and Environmental Soil Science ◽

10.1155/2014/703460 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 6

Author(s):

Mark A. Liebig ◽

David W. Archer ◽

Don L. Tanaka

Keyword(s):

Agricultural Land ◽

Cropping Systems ◽

Cropping System ◽

Soil Condition ◽

Crop Diversity ◽

Northern Great Plains ◽

Total N ◽

Near Surface ◽

Organic C ◽

South Central

Unprecedented changes in agricultural land use throughout the northern Great Plains of North America have highlighted the need to better understand the role of crop diversity to affect ecosystem services derived from soil. This study sought to determine the effect of four no-till cropping systems differing in rotation length and crop diversity on near-surface (0 to 10 cm) soil properties. Cropping system treatments included small grain-fallow (SG-F) and three continuously cropped rotations (3 yr, 5 yr, and Dynamic) located in south-central North Dakota, USA. Soil pH was lower in the 3 yr rotation (5.17) compared to the Dynamic (5.51) and SG-F (5.55) rotations(P≤0.05). Among cropping system treatments, 5 yr and Dynamic rotations possessed significantly greater soil organic C (SOC) and total N (mean = 26.3 Mg C ha−1, 2.5 Mg N ha−1) compared to the 3 yr (22.7 Mg C ha−1, 2.2 Mg N ha−1) and SG-F (19.9 Mg C ha−1, 2.0 Mg N ha−1) rotations(P≤0.05). Comparison of SOC measured in this study to baseline values at the research site prior to the establishment of treatments revealed only the 5 yr and Dynamic rotations increased SOC over time. The results of this study suggest that a diverse portfolio of crops is necessary to minimize soil acidification and increase SOC.

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Effect of continuous casting speed on mold surface flow and the related near-surface distribution of non-metallic inclusions

International Journal of Minerals Metallurgy and Materials ◽

10.1007/s12613-019-1723-y ◽

2019 ◽

Vol 26 (2) ◽

pp. 186-193 ◽

Cited By ~ 1

Author(s):

Peng Fei ◽

Yi Min ◽

Cheng-jun Liu ◽

Mao-fa Jiang

Keyword(s):

Continuous Casting ◽

Casting Speed ◽

Surface Flow ◽

Mold Surface ◽

Surface Distribution ◽

Near Surface ◽

Metallic Inclusions

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Seismic and potential‐field imaging of the Guichon Creek batholith, British Columbia, Canada, to delineate structures hosting porphyry copper deposits

Geophysics ◽

10.1190/1.1444831 ◽

2000 ◽

Vol 65 (5) ◽

pp. 1418-1434 ◽

Cited By ~ 31

Author(s):

Baishali Roy ◽

Ron M. Clowes

Keyword(s):

British Columbia ◽

Seismic Reflection ◽

Porphyry Copper ◽

Regional Scale ◽

Low Grade ◽

Depth Range ◽

Porphyry Copper Deposits ◽

Near Surface ◽

Copper Deposits ◽

South Central

The Guichon Creek batholith (GCB), located in south‐central British Columbia, contains several large, low‐grade copper deposits of considerable economic importance. The surface geology of the Guichon batholith and its surrounding region have been well mapped; however, little information about subsurface features is available. The batholith consists of four major phases, emplaced radially outward, which can be separated on the basis of their texture and composition. Previous interpretation of gravity data suggests a mushroom‐shaped structure for the batholith. Data from Lithoprobe seismic reflection line 88-11, acquired across the batholith in 1988, reveal weakly coherent east‐dipping reflections on the west side and west‐dipping reflections on the east in the upper 10 km. To determine if these are related to structures associated with the batholith, we reprocessed the upper 6 s with particular emphasis on applications of signal enhancement techniques (e.g., pattern recognition methods, refraction statics, dip moveout corrections) and correlation of the improved subsurface images with the geological environment associated with porphyry copper deposits. Low near‐surface velocities correlate well with the phases of the batholith hosting the major copper deposits, which structurally lie in faulted and brecciated regions. Although the top 1.5 km cannot be imaged by the regional‐scale seismic reflection data, the reprocessed seismic section helps define the edges of the batholith, its various concentric phases, and the stem in the depth range of 1.5 to 10 km. The seismic results are complemented by 2.5-D (profile sense) modeling and 3-D inversion of regional‐scale gravity and high‐resolution aeromagnetic data. These show a low‐density and low‐magnetic‐susceptibility region associated with the batholith that extends to more than 10 km depth. The region of active mining interest lies above a circular low‐susceptibility area at 2 km depth and a low‐velocity region. Integrated interpretation of geophysical results and geological observations indicates the GCB is a funnel‐shaped feature in which mineralization is located above the stem of the batholith.

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