scholarly journals Age and provenance of mica-schist pebbles from the Eocene conglomerates of the Tylicz and Krynica Zone (Magura Nappe, Outer Flysch Carpathians)

2016 ◽  
Vol 67 (3) ◽  
pp. 260-274 ◽  
Author(s):  
Nestor Oszczypko ◽  
Dorota Salata ◽  
Patrik Konečný
Keyword(s):  
Shallow Water ◽  
Age Distribution ◽  
Source Area ◽  
Crystalline Rocks ◽  
Mica Schist ◽  
Clastic Material ◽  
Monazite Dating ◽  
Source Areas ◽  
Flysch Carpathians ◽  
Pieniny Klippen Belt

Abstract During the Łate Cretaceous to Palaeogene, the Magura Basin was supplied by clastic material from source areas situated on the northern and southern margins of the basin, which do not outcrop on the surface at present. The northern source area is traditionally connected with the Silesian Ridge, whereas the position of the southern one is still under discussion. A source area situated SE of the Magura Basin supplied the Eocene pebbly para-conglomerates containing partly exotic material. The studied clastic material contains fragments of crystalline rocks, and frequent clasts of Mesozoic to Palaeogene deep and shallow-water limestones. Numerous mica schists, scarce volcanites and granitoids as well as gneisses, quartzites and cataclasites were found in the group of crystalline exotic pebbles. Monazite ages of “exotic” mica-schist pebbles from the Tylicz, Zarzecze and Piwniczna-Mniszek sections document the Variscan 310±10 Ma age of metamorphic processes. The provenance of these exotic rocks could be connected with a remote source area located SE of the Magura Basin, which could be the NW part of the Dacia Mega Unit. The idea is strongly supported by palaeotransport directions from the SE, the absence of material derived from the Pieniny Klippen Belt, the presence of shallow water limestones, typical facies of the Median Dacides belt and metamorphic age distribution proved by monazite dating.

scholarly journals Petrographical Analysis of Warthian Fuvioglacial Gravels as a Tool to Trace the Source Area – A Case Study From Central Poland

Geologos ◽  
2014 ◽  
Vol 20 (3) ◽  
pp. 183-199
Author(s):  
Maria Górska-Zabielska ◽  
Lucyna Wachecka-Kotkowska
Keyword(s):  
Ice Sheet ◽  
Source Area ◽  
Crystalline Rocks ◽  
Coarse Grained ◽  
Source Areas ◽  
Central Poland ◽  
Lower Palaeozoic ◽  
The Baltic

Abstract The petrographical features of the medium- and coarse-grained gravels (4-10 mm and 20-60 mm, respectively) of weathered and fresh (unweathered) deposits indicate, in combination with so-called indicator and statistical erratics, that two glacial lobes joined in the borderland of the Polish Lowlands and Uplands. Lower Palaeozoic limestones become less frequent in the fner gravel fraction, whereas crystalline rocks and fints become more frequent. The petrographical analysis of the coarser gravel fraction indicates that the ice sheet advanced from the NE to NNW (the Widawka lobe) and from the NE to ENE (the Rawka, Pilica and Luciąża lobes). The source areas of the gravel deposited by the Warthian ice sheet were magmatic and sedimentary areas of both the Baltic and the SE Sweden basins.

scholarly journals STUDIUM SPODNOBADENSKÝCH BAZÁLNÍCH KLASTIK V OBLASTI PODZEMNÍHO ZÁSOBNÍKU PLYNU LOBODICE

2014 ◽  
Vol 21 (1-2) ◽  
Author(s):  
David Blaško ◽  
Slavomír Nehyba ◽  
Anita Bartakovics
Keyword(s):  
Depositional Environment ◽  
Sedimentary Rocks ◽  
Outer Part ◽  
Source Area ◽  
Crystalline Rocks ◽  
Source Material ◽  
Coarse Grained ◽  
Source Areas ◽  
Traction Current ◽  
Analysis Point

The depositional environment and the provenance of the Lower Badenian basal clastics in the area of Lobodice subsurface gas storage were described during the studies of these sediments.Drill cores of Lobodice wells were studied in the total length of 110 m for the purpose of depositional environment evaluation. The textures and structures were described on these cores and on this basis three lithofacies were recognized. The lithofacies A is represented by grey matrix supported, granule conglomerate, very poorly sorted. This lithofaces has been interpreted as the product of deposition of a coarse grained delta. The lithofacies B is formed by fine and medium sandstone with ripple cross lamination, very well sorted sandstone. This facies was interpreted as the result of a relatively low energy of traction current, probably deposited in marine environment. The lithofacies C is formed by greyish clay siltstone, locally with planar lamination and common bioturbation. The lithofacies C was interpreted as the product of deposition in the off shore condition (outer part of the shelf?).The results of pebble analysis and analysis of the chemistry of garnets and rutiles were used for the evaluation of the source areas of the Lower Badenian basal clastics.Pebble analysis shows that the studied Lower Badenian clastics are polymict. Grey limestones dominate in the pebble spectra and also oft en represent the largest clasts. Light-coloured limestones, shales and graywackes (most probably Culmian), quartzes and dolomites are relatively common. The content of pebbles of crystalline rocks is relative low. These results indicate the prevalence of sedimentary rocks in the source area and/or recycling of the source material. This results together with garnet and rutile analysis point to the source from the Culmian rock of Drahanská Vrchovina Upland and Nízký Jeseník Highland (especially the rocks of the Myslejovice Formation) and also probably from the Carpathian Flysch Belt.

scholarly journals An efficient semi-distributed hillslope erosion model for the subhumid Ethiopian Highlands

2013 ◽  
Vol 17 (3) ◽  
pp. 1051-1063 ◽  
Author(s):  
S. A. Tilahun ◽  
C. D. Guzman ◽  
A. D. Zegeye ◽  
T. A. Engda ◽  
A. S. Collick ◽  
...  
Keyword(s):  
Surface Runoff ◽  
Source Area ◽  
Sediment Concentration ◽  
Erosion Model ◽  
Ethiopian Highlands ◽  
Source Areas ◽  
Blue Nile Basin ◽  
Field Evidence ◽  
Sediment Loss ◽  
Main Variable

Abstract. Erosion modeling has been generally scaling up from plot scale but not based on landscape topographic position, which is a main variable in saturation excess runoff. In addition, predicting sediment loss in Africa has been hampered by using models developed in western countries and do not perform as well in the monsoon climate prevailing in most of the continent. The objective of this paper is to develop a simple erosion model that can be used in the Ethiopian Highlands in Africa. We base our sediment prediction on a simple distributed saturated excess hydrology model that predicts surface runoff from severely degraded lands and from bottom lands that become saturated during the rainy season and estimates interflow and baseflow from the remaining portions of the landscape. By developing an equation that relates surface runoff to sediment concentration generated from runoff source areas, assuming that baseflow and interflow are sediment-free, we were able to predict daily sediment concentrations from the Anjeni watershed with a Nash–Sutcliffe efficiency ranging from 0.64 to 0.78 using only two calibrated sediment parameters. Anjeni is a 113 ha watershed in the 17.4 million ha Blue Nile Basin in the Ethiopian Highlands. The discharge of the two watersheds was predicted with Nash–Sutcliffe efficiency values ranging from 0.80 to 0.93. The calibrated values in Anjeni for degraded (14%) and saturated (2%) runoff source area were in agreement with field evidence. The analysis suggests that identifying the runoff source areas and predicting the surface runoff correctly is an important step in predicting the sediment concentration.

scholarly journals HEAVY CLASTIC MINERALS AS AN INDICATOR OF GEODYNAMIC SETTINGS OF ACCUMULATION AND PROVENANCE OF CRETACEOUS SEDIMENTS OF THE WEST SAKHALIN TERRANE

2021 ◽  
pp. 68-86
Author(s):  
A.I. Malinovsky ◽  
Keyword(s):  
Large Scale ◽  
Volcanic Rocks ◽  
Source Area ◽  
Heavy Minerals ◽  
Clastic Material ◽  
The West ◽  
Geodynamic Settings ◽  
Eurasian Continent ◽  
Ocean Boundary ◽  
By Products

The article discusses the results of studying heavy clastic minerals from the Cretaceous sandy rocks of the West Sakhalin Terrane, and also presents their paleogeodynamic interpretation. It is shown that in terms of mineralogical and petrographic parameters, the terrane sandstones correspond to typical graywackes and are petrogenic rocks formed mainly by destruction of igneous rocks of the source areas. The sediments were found to contain both sialic, granite-metamorphic association minerals, and femic, formed by products of the destruction of basic and ultrabasic volcanic rocks. The interpretation of the entire set of data on the content, distribution and microchemical composition of heavy minerals was carried out by comparing them with minerals from older rocks and modern sediments accumulated in known geodynamic settings. The results obtained indicate that during the Cretaceous, sedimentation occurred along the continent-ocean boundary in a basin associated with large-scale left-lateral transform movements of the Izanagi Plate relative to the Eurasian continent. The source area that supplied clastic material to that basin combined a sialic landmass composed of granite-metamorphic and sedimentary rocks, a mature deeply dissected ensialic island arc, and fragments of accretion prisms, in the structure of which involved ophiolites.

Spatial heterogeneity of debris-flow watershed

2021 ◽  
Author(s):  
Yingjie Yao
Keyword(s):  
Potential Energy ◽  
Debris Flow ◽  
Spatial Autocorrelation ◽  
Gravitational Potential ◽  
Source Area ◽  
Geospatial Analysis ◽  
Gravitational Potential Energy ◽  
Source Areas ◽  
Hypsometric Analysis ◽  
Inflection Points

<p>The intermittent surge is the basic manifestation of viscous debris flow, which emerges universally over the world, especially exemplified by those in Jiangjia Gully (JJG), a valley famous for its high frequency and variety of debris flow surges. It has been found that the surges originate from various sources in the watershed, thus identifying the source areas plays a fundamental role in studying the mechanism and process of surge developing. Advancement of GIS provides an apparent convenience in geospatial analysis of the watershed, which is used as a dominate tool in this paper.</p><p>In this study the JJG is divided into 97 tributaries (sub-watershed) and the hypsometric analysis is performed for each, from which derive the height of inflection points and the gravitational potential energy, coupled with the fitted parameters of specific power function. Then the morphology parameters, including slope, roundness, vegetation and soil, are revealed in tributaries. Besides, spatial autocorrelation among tributaries is quantified both globally and locally through Moran’s I and Getis-Ord G<sub>i</sub>*, so that the HI spatial distributions are quantified and visualized. In particular, hot spots are conspicuously visible and highlight the geologic meaning of the HI when exploratory spatial data analysis is applied to the data distributions through local indices of spatial autocorrelation.</p><p>The results show that H-curves approximately present as S-shaped, and the integral values (HI) range from 0.18 to 0.69 and show positive relationship with both gravitational potential energy and the height of the inflection points. By the HI value, the tributaries are identified as in 5 phases of evolution. The younger tributaries (HI>0.49) make up the majority, which are expected to be the main possible sources for debris flows. Additionally, the slope distribution of tributaries all conform to the extreme distribution while the curves for the upstream, where the HI of tributaries generally manifest higher coupled with larger roundness, tends to skew to the right.</p><p>Finally the correlation between possible sources are explored through geospatial analysis. The spatial association in JJG provides an explanation of the debris flow source areas. Global spatial autocorrelation manifests significantly clustered (Moran’s I shows 0.449, passing the significance test) while tributaries with high HI value concentrate mainly in the Menqian Valley. Moreover, the drainage form of Menqian Valley represents a large possibility of debris flow source area with the respect of that being in Duozhao Valley.</p><p><strong>Keywords: </strong>debris flow source area; hypsometric analysis; topographical characteristics; spatial autocorrelation; evolutionary phases</p>

scholarly journals The Occurrence and Risks of Selected Emerging Pollutants in Drinking Water Source Areas in Henan, China

2019 ◽  
Vol 16 (21) ◽  
pp. 4109 ◽  
Author(s):  
Donghai Wu ◽  
Ying Zhou ◽  
Guanghua Lu ◽  
Kai Hu ◽  
Jingjing Yao ◽  
...  
Keyword(s):  
Drinking Water ◽  
Hazard Index ◽  
Source Area ◽  
Dry Weight ◽  
Water Source ◽  
Triphenylphosphine Oxide ◽  
Drinking Water Source ◽  
Uv Filters ◽  
Source Areas ◽  
Total Concentrations

The occurrence of organic micropollutants (OMPs) in aqueous environments has potential effects on ecological safety and human health. Three kinds of OMPs (namely, pharmaceuticals, ultraviolet (UV) filters and organophosphate esters (OPEs)) in four drinking water source areas in Henan Province of China were analyzed, and their potential risks were evaluated. Among 48 target chemicals, 37 pollutants with total concentrations ranging from 403.0 to 1751.6 ng/L were detected in water, and 13 contaminants with total concentrations from 326.0 to 1465.4 ng/g (dry weight) were observed in sediment. The aqueous pollution levels in Jiangang Reservoir and Shahe Water Source Area were higher than that in Nanwan Reservoir and Baiguishan Reservoir, while the highest total amount of pollutants in sediment was found in Baiguishan Reservoir. Compared with pharmaceuticals and UV filters, OPEs presented higher concentrations in all investigated drinking water source areas. The highest observed concentration was triphenylphosphine oxide (TPPO, 865.2 ng/L) in water and tripentyl phosphate (TPeP, 1289.8 ng/g) in sediment. Moreover, the risk quotient (RQ) analysis implies that the determined aqueous contaminants exhibited high risks to algae and invertebrates, whereas moderate risk to fish was exhibited. The health risk assessment of aqueous OMPs by means of the hazard index (HI) indicates that the risks to adults and children were negligible. These observations are expected to provide useful information for the assessment of water quality in drinking water sources in Henan, China.

scholarly journals Rural Households’ Willingness to Accept Compensation Standards for Controlling Agricultural Non-Point Source Pollution: A Case Study of the Qinba Water Source Area in Northwest China

Water ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 1251 ◽  
Author(s):  
Xiaoping Li ◽  
Wenxin Liu ◽  
Yan Yan ◽  
Gongyuan Fan ◽  
Minjuan Zhao
Keyword(s):  
Rural Households ◽  
Source Area ◽  
Water Source ◽  
Willingness To Accept ◽  
Point Source Pollution ◽  
Ecological Benefits ◽  
Source Areas ◽  
Compensation Standard ◽  
Non Point Source Pollution ◽  
Willingness To Accept Compensation

Agricultural non-point source pollution (ANSP) has become one of the main sources of pollution in water source areas. An effective solution to this problem is the use of ecological compensation to encourage rural households to adopt agricultural pollution control measures. This study aims to answer two questions: How much compensation should be given to encourage rural households in water source areas to participate in ANSP control? What factors will influence their participation? In this study, paddy rice planting in water source area has been used as an example aiming to answer these questions. This study used the random parameter logit (RPL) model with survey data from 632 rural households in the Qinba water source area to empirically analyze rural households’ willingness to accept compensation for ANSP control and the influencing factors of this willingness. From this information, the compensation standards for ANSP control in a water source area were calculated. The results show that (1) compensation had a significant incentive effect on rural households’ willingness to control ANSP. The marginal compensation standard for reducing the use of fertilizer and pesticide was $3.40/ha and $2.00/ha, respectively. The compensation standard for not applying chemical fertilizer and pesticide at all was $540.23/ha. (2) There was heterogeneity in rural households’ preference for ANSP control compensation policies. Rural households characterized by younger residents, higher family income, higher perception of the ecological benefits, and higher perception of government policy were more willing to participate in the compensation policy. It is suggested that rural households showed a strong preference for ANSP control policies by considering both of their economic losses and ecological benefits. Our study contributes to the literature by enriching the evaluation method in providing references for the compensation of ANSP control policies

Resistance of zircons to U–Pb resetting in a prograde metamorphic sequence of Caledonian age in East Greenland

1985 ◽  
Vol 22 (3) ◽  
pp. 330-338 ◽  
Author(s):  
J. J. Peucat ◽  
D. Tisserant ◽  
R. Caby ◽  
N. Clauer
Keyword(s):  
Source Area ◽  
Detrital Zircons ◽  
Metamorphic Event ◽  
Great Resistance ◽  
East Greenland ◽  
Geological Interpretation ◽  
Source Areas ◽  
Metasedimentary Rocks ◽  
Sedimentary Source

In the Alpefjord area, Caledonian metamorphism from the chlorite zone to the sillimanite zone is seen to cut across the sedimentary pile of the lower Eleonore Bay Group. Zircons have been collected from quartzite layers enriched in heavy minerals.U–Pb zircon dating in the chlorite and the sillimanite zones does not reveal the Caledonian event but, instead, previous episodes at 1100 and 2500 Ma ago. The Caledonian event can be recognized in anatectic gneisses where detrital zircons are surrounded by overgrowths, K–Ar and Rb–Sr methods yield 1030–410 Ma ages on micas, with a positive correlation between the degree of apparent reselling of mica ages and the grade of the Caledonian metamorphism.The following geological interpretation of the age data is proposed. (1) A major metamorphic event occurred around 1100 Ma ago in the source area for the lower Eleonore Bay Group sediments. During this Grenvillian event, Archaean detrital zircons were affected by an episodic lead loss and a muscovite phase recorded the cooling and uplift of a basement source area. (2) Erosion of this source area occurred after 1100 Ma, followed by sedimentation of the lower Eleonore Bay Group [Formula: see text]. The 2500–1100 Ma U–Pb system remained nearly a closed system during Caledonian metamorphism up to and including sillimanite-zone conditions.This example shows the great resistance or inherited zircons to an important secondary Pb loss during Caledonian metamorphism and consequently shows that the lower-intercept ages of zircons from metasedimentary rocks do not always record the last metamorphic event observed in situ, but retain memories of previous geological events in the sedimentary source areas. By contrast, zircons separated from quartzitic xenoliths in migmatitic gneisses have recorded a disturbance in their U–Pb systems that corresponds to Caledonian partial melting.

Jurassic-Cretaceous paleogeography of Central-West Parnaiba Basin, NE Brazil - stratigraphy and sedimentary provenance of detrital zircons

2020 ◽  
Author(s):  
André Pereira de Assis ◽  
Kelly Aparecida Caldas da Cruz ◽  
Renata da Silvia Schmitt ◽  
Silvia Regina de Medeiros
Keyword(s):  
Detrital Zircon ◽  
Source Area ◽  
Depositional Environments ◽  
Detrital Zircons ◽  
Hypersaline Lake ◽  
Red Sandstone ◽  
Source Areas ◽  
Aeolian Dunes ◽  
Marine Ingression ◽  
And Shifts

<p><span>The Phanerozoic Parnaíba Basin occupies 600.000km² in northeast Brazil, covering cratons and Neoproterozoic belts. Its Central-West region is mostly represented by the Jurassic-Cretaceous Sequence (Mosquito, Corda Grajaú, Codó and Itapecuru formations) recording magmatic events from the Central Atlantic Magmatic Province, with depocenters migrations and shifts on depositional environments related to Pangea breakup.<span>  </span>This work discusses the Jurassic-Cretaceous siliciclastic units testing possible sedimentary source areas with U-Pb and combined Lu-Hf data on detrital zircons, using LA-ICP-MS. The basalts from Mosquito Formation are dated at +/- 198Ma and the Codó Formation present accurate Aptian fossil data. This formation records a hypersaline lake system, succeeded by a transgression that represents pioneer marine ingression within an intracontinental rift. The other units (Corda, Grajaú and Itapecuru) are constituted by siliciclastic sediments involved in intracontinental sub-environments. The Corda Formation consists of aeolian system, sand sheets and <em>wadis</em> deposited in a desertic setting. The contact between the subsequent Grajaú Formation is abrupt, represented, at the base, by thick coarse braided river facies grading laterally and upwards to ephemeral channels in association with low amplitude Aeolian dunes, evidencing still arid conditions. Interlayered beds of fluvial and aeolian sandstones within lacustrine deposits, indicates that Codó and Grajaú formations consists the same seasonal fluvial-lacustrine system. The last Itapecuru Formation, is represented by a thick red sandstone succession deposited in a deltaic system. Paleocurrents measurements below Codó Formation (i.e. Corda and lower Grajaú) points a W-NW sense of direction, whereas paleocurrents above Codó Formation (i.e. upper Grajaú and Itapecuru) presents a regional sense to E-NE. Detrital zircons geochronology analysis helped to identify the source area of sediments through the comparison of the main ages of possible uplifted tectonic terranes. The preliminary results revealed that sandstones below Codó Formation shows a major Neoproterozoic population (56, 41% to 40%) with age peaks at 583 and 628 Ma; and also Paleoproterozoic (43, 48% to 35,05%); Archean (4,35%) and Paleozoic (2,61%) populations. Sandstones above Codó Formation, also show a Neoproterozoic major detrital zircon population (40% to 37,12%) with 625, 665 and 783 Ma age peaks. Two other populations are present: Paleoproterozoic (22.68% to 20%) with peaks at 1749 and 1881 Ma, and Archean (24,45% to 15,47%). This last source has a greater contribution than in the formations below the Codó maker. We envisaged that the shift from W-NW to E-NE sandstones paleocurrent is coherent with the rise on Archean contribution, possibly related to the Amazon Craton to the West. In addition, the youngest Phanerozoic detrital zircons obtained in all samples are minor (6,66% to 6,18%). The integration of field stratigraphic analysis, paleocurrents and detrital zircon provenance studies corroborate to the hypothesis that Codó Formation must represent a Cretaceous stratigraphic datum for the transition of a rift and post-rift phase, thus the change of source areas is consistent. </span></p><p><span>The authors acknowledge support from Shell Brasil Petroleo Ltda. and ANP (Brazil’s National Oil, Natural Gas and Biofuels Agency) through the R&D levy regulation (Technichal Cooperation #20.219-2).</span></p>

Numerical Simulation on Ghosting Fire in the Confined Underground Space

2014 ◽  
Vol 580-583 ◽  
pp. 2667-2670
Author(s):  
Pei Hong Zhang ◽  
Xiao Wei Lu ◽  
Xiao Ming Zhang
Keyword(s):  
Heat Release ◽  
Heat Release Rate ◽  
Release Rate ◽  
Source Area ◽  
Confined Space ◽  
Source Areas ◽  
Fire Source ◽  
Underground Fire ◽  
Two Parameters ◽  
Air Vent

The phenomenon of ghosting fire development in underground confined space is simulated to analyze the impacts of ghosting fire generation via some conditions -- different air vent sizes and different fire source areas. FDS is used to establish a physical model of underground fire laboratory in Northeastern University, the simulation is conducted by setting two parameters, the air vent size and the fire source area. The fire heat release rate, temperature, concentration of CO, O2 are measured to analyze the case of ghosting fire generation in underground confined space with different air vent sizes and different fire source areas. It’s most likely to generate ghosting fire when the simulating parameter is that the air vent size is 0.4m × 0.4m and the fire source area is 0.96m2. The conclusion is that increasing the air vent size is not a simple ascending and descending relationship with the occurrence time and duration time of the ghosting fire. Increasing the fire source area can improve the fire heat release rate effectively, and promote the formation of ghosting fire.

Sign in / Sign up

Export Citation Format

Share Document