Understanding of subsurface conditions controlling flow liquefaction occurrence during the 2018 Palu earthquake based on resistivity profiles

The 7.4 Mw earthquake on 28th September 2018 in Palu City triggered a flow liquefaction phenomenon in the Balaroa and Petobo areas, contributing to significant casualties and building damage. This paper presents the results of a liquefaction study to map subsurface conditions in these areas using the multi-electrode resistivity method with the dipole-dipole configuration. The objective of this study is to understand factors controlling the flow liquefaction phenomenon. Based on the interpretation of 2-D resistivity images, the liquefied soil layers are characterized by lower resistivity values than the non-liquified layers. These contrasts of resistivity values form a gently sloping boundary between the liquefied and non-liquefied soil layers. The resistivity image perpendicular to the flow direction indicates the presence of a subsurface basinal morphology in the Balaroa area, suggesting that a shallow groundwater zone is present within the liquefiable soil layer. Thus, the subsurface topographical condition is the main governing factor of flow liquefaction phenomena during the 2018 Palu earthquake.

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Investigasi Air Tanah di Daerah Sea Kabupaten Minahasa Dengan Menggunakan Geolistrik Resistivitas Konfigurasi Dipol-Dipol

Jurnal MIPA ◽

10.35799/jmuo.9.1.2020.26914 ◽

2019 ◽

Vol 9 (1) ◽

pp. 1

Author(s):

Adey Tanauma ◽

Herling Daud Tangkuman ◽

Mesike Sangi

Keyword(s):

Ground Water ◽

Vegetation Type ◽

Soil Layer ◽

Resistivity Method ◽

Groundwater Aquifers ◽

Resistivity Model ◽

Geoelectric Resistivity ◽

Dipole Configuration ◽

Subsurface Resistivity ◽

Measurement Line

Penyebaran air tanah yang tidak merata dipengaruhi oleh faktor-faktor jenis batuan, bentuk topografi permukaan, jenis vegetasi dan jumlah curah hujan suatu tempat. Eksplorasi geofisika metode geolistrik tahanan jenis konfigurasi dipol-dipol digunakan untuk mengidentifikasi sebaran akuifer air tanah di desa Sea Kabupaten Minahasa. Data diolah menggunakan software Res2Dinv dan menghasilkan peta model resistivitas bawah permukaan 2 dimensi yang menggambarkan keadaan lapisan tanah. Teridentifikasi sebaran akuifer air tanah permukaan dengan kedalaman ≤ 20 m di sepanjang lintasan pengukuran. Akuifer air tanah dalam diidentifikasi pada lintasan 1 dengan kedalaman sampai 30 m dan 60 m. Akuifer air tanah dengan kedalaman< 60 m mempunyai potensi dijadikan sebagai sumber air tanahThe uneven distribution of ground water is influenced by factors such as rock type, surface topography, vegetation type and the amount of rainfall in a place. Geophysical exploration of the dipole-dipole configuration type of geoelectric resistivity method is used to identify the distribution of groundwater aquifers in Sea village, Minahasa District. The data is processed using Res2Dinv software and produces a 2-dimensional subsurface resistivity model map that describes the state of the soil layer. Distribution of surface ground aquifer with a depth of ≤ 20 m along the measurement line was identified. Deepwater aquifers were identified in l1ne 1 with depths up to 30 m and 60 m. Groundwater aquifers with a depth of <60 m have the potential to be used as ground water sources

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PENENTUAN KEDALAMAN SUMUR BOR BERDASARKAN DATA GEOLISTRIK RESISTIVITAS DI BEBERAPA KAMPUNG DI KABUPATEN FAK-FAK

Jurnal Natural ◽

10.30862/jn.v14i1.11 ◽

2018 ◽

Vol 14 (1) ◽

pp. 37-44

Author(s):

Khristian Enggar Pamuji

Keyword(s):

Water Layer ◽

Water Source ◽

Water Infiltration ◽

Resistivity Sounding ◽

Subsurface Geology ◽

Resistivity Method ◽

Groundwater Aquifers ◽

Dipole Configuration ◽

Geoelectrical Resistivity ◽

Resistivity Image

Geoelectrical Resistivity method is a geophysical method that can be used to determine subsurface geology based on rock resistivity image. Resistivity survey has been done in some villages, in Fak Fak Regency, West Papua Province. The measurement method that used is sounding, whereas electrode configuration used is Dipole-dipole configuration with a stretch of 100 -150 m. The data obtained are then processed by Progress Res2Dinv. The results of this survey obtained show that in the resistivity sounding measurement point found any good groundwater aquifers, as the water source of drilled well. Water layer with the thickness between 1-3 m at the surface (alluvial) is a rain water infiltration that is not recommended to make boreholes at this point.

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The Estimation of Subsurface Structure within Geothermal Manifestation Area as an Outflow Zone Using Geoelectrical Resistivity Method in Tegal, Jawa Tengah

GeoEco ◽

10.20961/ge.v7i1.42392 ◽

2021 ◽

Vol 7 (1) ◽

pp. 1

Author(s):

Hangga Novian Adi Putra ◽

Wahyudi Wahyudi

Keyword(s):

Research Result ◽

Soil Layer ◽

Normal Fault ◽

Geothermal Field ◽

Geothermal System ◽

Resistivity Method ◽

Geothermal Fields ◽

Dipole Configuration ◽

Geoelectrical Resistivity ◽

Manifestation Area

Indonesia is one of the country having a lot of geothermal fields potentially used as a source of energy. For example, Java island is noted to have almost 57 geothermal fields. One of those geothermal fields which is rarely studied is Guci geothermal field. Hence, there was conducted a research to investigate the subsurface image and geothermal system in Guci geothermal field based on resistivity data. The research in Guci geothermal field was carried out using geoelectrical method. Resistivity geoelectrical research used two configurations, namely dipole-dipole and schlumberger. Data acquisitions for dipole-dipole configuration was done in two lines, 500 metres spread for each line. Whereas the acquisitions for schlumberger configuration was done in four points, 200-250 metres spread for each point. Research result showed that the area of geothermal manifestation in Guci consist of top soil layer, sandstone, andesite, and a fluids-containing layer. A fluids-containing layer is estimated to be related to geothermal manifestation in Guci and is a fault zone. Fault is estimated to be a normal fault and lies in 20 metres depth. Fault within geothermal manifestation area in Guci has a role as the pathway of hot-fluid out to the surface which forms a manifestation.

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Depth-Dependent C-N-P Stocks and Stoichiometry in Ultisols Resulting from Conversion of Secondary Forests to Plantations and Driving Forces

Forests ◽

10.3390/f12101300 ◽

2021 ◽

Vol 12 (10) ◽

pp. 1300

Author(s):

Xiaogang Ding ◽

Xiaochuan Li ◽

Ye Qi ◽

Zhengyong Zhao ◽

Dongxiao Sun ◽

...

Keyword(s):

Soil Depth ◽

Soil Layer ◽

Pinus Elliottii ◽

Slash Pine ◽

Pine Plantations ◽

Secondary Forests ◽

Masson Pine ◽

Soil Layers ◽

Soil C ◽

Significant Difference

Stocks and stoichiometry of carbon (C), nitrogen (N), and phosphorus (P) in ultisols are not well documented for converted forests. In this study, Ultisols were sampled in 175 plots from one type of secondary forest and four plantations of Masson pine (Pinus massoniana Lamb.), Slash pine (Pinus elliottii Engelm.), Eucalypt (Eucalyptus obliqua L’Hér.), and Litchi (Litchi chinensis Sonn., 1782) in Yunfu, Guangdong province, South China. Five layers of soil were sampled with a distance of 20 cm between two adjacent layers up to a depth of 100 cm. We did not find interactive effects between forest type and soil layer depth on soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) concentrations and storages. Storage of SOC was not different between secondary forests and Eucalypt plantations, but SOC of these two forest types were lower than that in Litchi, Masson pine, and Slash pine plantations. Soil C:P was higher in Slash pine plantations than in secondary forests. Soil CNP showed a decreasing trend with the increase of soil depth. Soil TP did not show any significant difference among soil layers. Soil bulk density had a negative contribution to soil C and P stocks, and longitude and elevation were positive drivers for soil C, N, and P stocks. Overall, Litchi plantations are the only type of plantation that obtained enhanced C storage in 0–100 cm soils and diverse N concentrations among soil layers during the conversion from secondary forests to plantations over ultisols.

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Spatial and Temporal Variations of Nitrogen and Phosphorus in Surface Water and Groundwater of Mudong River Watershed in Huixian Karst Wetland, Southwest China

Sustainability ◽

10.3390/su131910740 ◽

2021 ◽

Vol 13 (19) ◽

pp. 10740

Author(s):

Linyan Pan ◽

Junfeng Dai ◽

Zhiqiang Wu ◽

Liangliang Huang ◽

Zupeng Wan ◽

...

Keyword(s):

Surface Water ◽

Temporal Dynamics ◽

Flow Direction ◽

Influencing Factor ◽

Shallow Groundwater ◽

Temporal Variations ◽

Field Investigation ◽

Spatial And Temporal Variation ◽

Nitrogen And Phosphorus ◽

River Watershed

When considering the factors affecting the spatial and temporal variation of nitrogen and phosphorus in karst watersheds, the unique karst hydrogeology as an internal influencing factor cannot be ignored, as well as natural factors such as meteorological hydrology and external factors such as human activities. A watershed-scale field investigation was completed to statistically analyze spatial and temporal dynamics of nitrogen and phosphorus through the regular monitoring and collection of surface water and shallow groundwater in the agricultural-dominated Mudong River watershed in the Huixian Karst Wetland over one year (May 2020 to April 2021). Our research found that non-point source pollution of nitrogen (84.5% of 239 samples TN > 1.0 mg/L) was more serious than phosphorus (7.5% of 239 samples TP > 0.2 mg/L) in the study area, and shallow groundwater nitrogen pollution (98.3% of 118 samples TN > 1.0 mg/L) was more serious than surface water (68.6% of 121 samples TN > 1.0 mg/L). In the three regions with different hydrodynamic features, the TN concentration was higher and dominated by NO3−-N in the river in the northern recharge area, while the concentrations of TN and TP were the highest in shallow groundwater wells in the central wetland core area and increased along the surface water flow direction in the western discharge area. This research will help improve the knowledge about the influence of karst hydrodynamic features on the spatial patterns of nitrogen and phosphorus in water, paying attention to the quality protection and security of water in karst areas with a fragile water ecological environment.

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Grazing and Cultivated Grasslands Cause Different Spatial Redistributions of Soil Particles

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph16152639 ◽

2019 ◽

Vol 16 (15) ◽

pp. 2639 ◽

Cited By ~ 1

Author(s):

Jinsheng Li ◽

Jianying Shang ◽

Ding Huang ◽

Shiming Tang ◽

Tianci Zhao ◽

...

Keyword(s):

Soil Layer ◽

Soil Health ◽

Grazing Intensity ◽

Health Condition ◽

Soil Particle ◽

Particle Sizes ◽

Soil Layers ◽

Soil Particles ◽

Heavy Grazing ◽

Grazing Intensities

The distribution of soil particle sizes is closely related to soil health condition. In this study, grasslands under different grazing intensities and different cultivation ages grasslands were selected to evaluate the dynamics of soil particle size redistribution in different soil layers. When the grazing intensity increased, the percentage of 2000~150-μm soil particles in the 0–10-cm soil layer decreased; 150~53-μm soil particles remained relatively stable among the grazing intensities—approximately 28.52%~35.39%. However, the percentage of less than 53-μm soil particles increased. In cultivated grasslands, the larger sizes (>53 μm) of soil particles increased and the smaller sizes (<53 μm) decreased significantly (p < 0.05) in the 0–10 cm-soil layer with increasing cultivation ages. The increase in small soil particles (<53 μm) in topsoil associated with grazing intensity increased the potential risk of further degradation by wind erosion. The increase in big soil particles (>53 μm) in topsoil associated with cultivation ages decreased the soil capacity of holding water and nutrient. Therefore, to maintain the sustainability of grassland uses, grazing grasslands need to avoid heavy grazing, and cultivated grasslands need to change current cultivation practices.

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Rooting patterns of Rumex species under drained conditions

Canadian Journal of Botany ◽

10.1139/b87-224 ◽

1987 ◽

Vol 65 (8) ◽

pp. 1638-1642 ◽

Cited By ~ 12

Author(s):

L. A. C. J. Voesenek ◽

C. W. P. M. Blom

Keyword(s):

Growth Rate ◽

Root Distribution ◽

Soil Layer ◽

The Other ◽

Rumex Acetosa ◽

Soil System ◽

Relative Growth ◽

Soil Layers ◽

Vertical Root Distribution ◽

Rooting Patterns

Root development and architecture were studied in three Rumex species growing in a perforated soil system in the greenhouse. Distinct differences in vertical root distribution under drained conditions were found among the three species. Rumex acetosa and R. palustris had a relatively superficial root pattern, whereas in R. crispus much of the root growth was concentrated in lower soil layers. In the upper soil layer the relative growth rate of the roots of R. palustris was significantly larger than that of the other species. A relation between the characteristic rooting patterns under drained conditions and the Rumex zonation in the field is discussed.

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Impact of Long-Term Reclaimed Water Irrigation on the Distribution of Potentially Toxic Elements in Soil: An In-Situ Experiment Study in the North China Plain

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph16040649 ◽

2019 ◽

Vol 16 (4) ◽

pp. 649 ◽

Cited By ~ 2

Author(s):

Xiaomin Gu ◽

Yong Xiao ◽

Shiyang Yin ◽

Honglu Liu ◽

Baohui Men ◽

...

Keyword(s):

Toxic Elements ◽

Reclaimed Water ◽

Soil Layer ◽

Shallow Groundwater ◽

Potentially Toxic Elements ◽

In Situ Experiment ◽

The North ◽

Reclaimed Water Irrigation

The widespread use of reclaimed water has alleviated the water resource crisis worldwide, but long-term use of reclaimed water for irrigation, especially in agricultural countries, might threaten the soil environment and further affect groundwater quality. An in-situ experiment had been carried out in the North China Plain, which aimed to reveal the impact of long-term reclaimed water irrigation on soil properties and distribution of potentially toxic elements (As, Cd, Cr, Hg, Zn and Pb) in the soil profile as well as shallow groundwater. Four land plots were irrigated with different quantity of reclaimed water to represent 0, 13, 22 and 35 years’ irrigation duration. Pollution Load Index (PLI) values of each soil layer were calculated to further assess the pollution status of irrigated soils by potentially toxic elements (PTEs). Results showed that long-term reclaimed water irrigation caused appreciable increase of organic matter content, and might improve the soil quality. High soil organic matter concentrations conduced to high adsorption and retention capacity of the soils toward PTEs, which could reduce the risk of PTEs leaching into deep layers or shallow groundwater. Highest levels of Cr, Pb and Zn were observed at 200–240 cm and 460–500 cm horizons in plots. Longer irrigation time (35 years and 22 years) resulted in a decreasing trend of As, Cd, Hg, Pb and Zn in lower part of soil profiles (>540 cm) compared with that with 13-years’ irrigation years. Long-term reclaimed water irrigation still brought about increases in concentrations of some elements in deep soil layer although their content in soils and shallow groundwater was below the national standard. Totally speaking, proper management for reclaimed water irrigation, such as reduction of irrigation volume and rate of reclaimed water, was still needed when a very long irrigation period was performed.

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Soil factors determined nematode community composition in a two year pot experiment

Nematology ◽

10.1163/156854103773040808 ◽

2003 ◽

Vol 5 (6) ◽

pp. 889-897 ◽

Cited By ~ 21

Author(s):

Bryan Griffiths ◽

Roy Neilson ◽

A. Glyn Bengough

Keyword(s):

Sandy Loam ◽

Soil Layer ◽

Principal Component ◽

Middle Layer ◽

Biological Properties ◽

Nematode Community ◽

Soil Factors ◽

Soil Layers ◽

Initial Inoculum ◽

Variable Water

Abstract Two similar, sandy loam soils from the same geographical region but with distinct nematode communities were used to determine the extent to which water, soil and inoculum factors affected nematode community structure. Treatments were established in pots containing a middle layer of frozen defaunated soil, sandwiched between an inoculum that was either fresh soil from the same site ('self') or a mixture of soils to give a more diverse inoculum ('mixed'). During year 2, half the pots were watered at regular intervals while the other half received only rainfall. For individual nematode taxa, soil layer and watering regime were the main factors discriminating between treatments, while initial inoculum had a larger influence than soil type. Acrobeloides was most affected by the watering regime, being more abundant under variable water conditions, whereas Hoplolaimidae, Longidorus and Pratylenchus were more abundant in deeper soil layers in contrast to other taxa. For the community as a whole, when analysed by principal component analysis, soil factors clearly influenced composition and also indicated that the biological properties of the soils were important.

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Stable Isotope Analysis of Water Uptake Sources of Primary Forests in the Central Yunnan Karst Plateau

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.864-867.2455 ◽

2013 ◽

Vol 864-867 ◽

pp. 2455-2458

Author(s):

Tao Fan ◽

Jie Li

Keyword(s):

Stable Isotope ◽

Stable Isotope Analysis ◽

Plant Uptake ◽

Rock Fracture ◽

Isotope Analysis ◽

Soil Layer ◽

Water Sources ◽

Soil Layers ◽

Cyclobalanopsis Glaucoides ◽

Primary Forests

Ecosystems in the central of Yunnan karst plateau are very fragile due to thin soil layer and intensive infiltration capacity of rock fracture, which result in a very limited amount of water storage for plant uptake. Water retention in the soil zone and shallow fractured rock zone (subcutaneous) is a key factor for plant growth. Distinction of water sources taken by karst plants is a challenging task for botanists and hydrologists but is needed for ecosystem management. In this study, stable isotope analysis was used to investigate water sources for Cyclobalanopsis glaucoides primary forests at Shilin Geopark in Bajiang vally, central Yunnan of China. Proportions of water sources for plant uptake were determined by the δD and δ18O values of plant stem water, and water taken from soil layers and the subcutaneous zone. The analysis reveals that water was mainly taken from the soil layers and to less degree the subcutaneous zone as well. In dry seasons with scarce precipitation, plants in the primary forest were prone to take more water from subcutaneous zone and deeper layer of soil. Different species had different water use strategies, Cyclobalanopsis glaucoides took a larger proportional water from the deeper layer of soil, suggesting its deeper roots and wider range of shallower roots. However, Olea yunnanensis and Pistacia weinmannifolia extracted more percentage of water from the deeper soil water and subcutaneous water because of its deeper roots.

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