Depositional environments and salt-thickness variations in Urmia Lake (NW Iran): Insight from sediment-core studies

2021 ◽  
Vol 91 (3) ◽  
pp. 296-316
Author(s):  
ALI MOHAMMADI ◽  
RAZYEH LAK ◽  
GEORG SCHWAMBORN ◽  
AMANEH KAVEH FIROUZ ◽  
ATTILA ÇINER ◽  
...  
Keyword(s):  
Water Depth ◽  
Depositional Environments ◽  
Urmia Lake ◽  
Aral Sea ◽  
Hypersaline Lake ◽  
Salt Deposition ◽  
Salt Crust ◽  
Thickness Variations ◽  
Evaporite Minerals ◽  
Crust Thickness

Abstract Urmia Lake is a large-scale hypersaline lake that experienced a drastic water-level fall due to natural and anthropogenic forces during the last two decades. Construction of a causeway in the central part of the lake after 1989 has divided the lake into northern and southern parts and caused an extreme change of the lake hydrochemical system. Precipitation of evaporite minerals as crust on the lake floor was caused by the combination of lake level fall and increasing water salinity. However, some parameters controlling rates of salt deposition and dissolution and temporal and spatial variation in salt thickness in Lake Urmia are poorly understood. This study reviews 90 sediment cores from various parts of the lake to put forward a better understanding of the salt depositional system and salt thickness variations in the basin for the last 40 years (1977–2017). Our results indicate that the sedimentary system of Urmia Lake changed rapidly during the last two decades from a permanent hypersaline lake with predominantly fast terrigenous–biochemical sedimentation to a seasonally changing playa sedimentary environment with predominance of evaporite minerals. These changes are responsible for rapid salt deposition that generated a salt-crust with a maximum thickness of 2.95 m overlying Holocene terrigenous sediments. The salt-crust thickness and the water depth have a positive correlation for water depth greater than 1 meter, which means that salt-crust thickness increases where water depth increases. While the thickness of shallow deposits are affected by fresh-water dissolution. In addition, the average salt precipitation rate in the northern and the southern parts of the lake is 466 and 266 times higher, respectively, than the average (0.3 mm/y) sedimentation rate before the lake shrinkage. Similar to other large hypersaline lakes such as the Great Salt Lake (USA) and the Aral Sea (Central Asia), the manmade intervention at Urmia Lake (damming of the catchment, extension of agricultural fields, and causeway construction in the middle part of the lake) threatens its further hydrologic existence.

The Evolution of the Paleo-Danube Deltas of the Lower Pannonian in the Vienna Basin 

2021 ◽  
Author(s):  
Arthur Borzi ◽  
Werner E. Piller ◽  
Mathias Harzhauser ◽  
Wolfgang Siedl ◽  
Philipp Strauss
Keyword(s):  
Water Depth ◽  
Foreland Basin ◽  
Eastern Alps ◽  
Depositional Environments ◽  
Terminal Phase ◽  
Vienna Basin ◽  
Lake Pannon ◽  
The North ◽  
Lateral Extrusion ◽  
North Alpine Foreland Basin

<p><strong>ABSTRACT</strong></p><p>The Vienna Basin is a rhombohedral SSW-NNE oriented Neogene extensional basin that formed along sinistral fault systems during Miocene lateral extrusion of the Eastern Alps. The basin fill consists of shallow marine and terrestrial sediments of early to late Miocene age reaching a thickness of 5500 m in the central part of the basin. The early Pannonian was a crucial time in the development of the Vienna Basin, as It coincided with the formation of Lake Pannon. The lake formed at 11.6 Ma when a significant regressive event isolated Lake Pannon from the Paratethys Sea, creating lacustrine depositional environments. At that time the delta of the Paleo-Danube started shedding its sediments into the central Vienna Basin. Based on an existing age model delta deposition commenced around 11.5 Ma and continued until 11.1 Ma. These subsurface deltaic deposits of the Hollabrunn-Mistelbach Formation represent the coeval fluvial deposits of the Paleo-Danube in the eastern plains of the North Alpine Foreland Basin. Therefore, the Palaeo-Danube represents an extraordinary case in where coeval fluvial and deltaic deposits of a Miocene river are continuously captured.</p><p>This study provides an interpretation of depositional architecture and depositional environments of this delta in the Austrian part of the central Vienna Basin based on the integration of 3D seismic surveys and well data. The mapped delta has an area of about 580 km<sup>2</sup>, and solely based on the geometry we classify the delta as a mostly river – dominated delta with significant influence of wave – reworking processes. For seven time slices paleogeographic maps are created, showing the interplay between the lacustrine environments of Lake Pannon, delta evolution and fluvial systems incising in the abandoned deltaplain. Onlaps between single deltalobes indicate a northward-movement of the main distributary channel. Approximate water-depth estimates are carried out with in-seismic measurements of the true vertical depth between the topset deposits of the delta and the base of the bottomset deposits. These data suggest a decrease of lake water depth from about 170 m during the initial phase of delta formation at 11.5 Ma to about 100 m during its terminal phase at 11.1 Ma. A major lake level rise of Lake Pannon around 11.1 Ma caused a flooding of the margins of the Vienna Basin, resulting in a back stepping of riverine deposits and termination of delta deposition in the study area.</p><p> </p>

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>

Urmia lake water depth modeling using extreme learning machine-improved grey wolf optimizer hybrid algorithm

2021 ◽  
Vol 146 (1-2) ◽  
pp. 833-849
Author(s):  
Ali Kozekalani Sales ◽  
Enes Gul ◽  
Mir Jafar Sadegh Safari ◽  
Hadi Ghodrat Gharehbagh ◽  
Babak Vaheddoost
Keyword(s):  
Extreme Learning Machine ◽  
Water Depth ◽  
Lake Water ◽  
Hybrid Algorithm ◽  
Urmia Lake ◽  
Grey Wolf Optimizer ◽  
Grey Wolf ◽  
Learning Machine ◽  
Improved Grey Wolf Optimizer

Habitat preference of mosasaurs indicated by rare earth element (REE) content of fossils from the Upper Cretaceous marine deposits of Alabama, New Jersey, and South Dakota (USA)

2014 ◽  
Vol 94 (1) ◽  
pp. 145-154 ◽  
Author(s):  
T.L. Harrell ◽  
A. Pérez-Huerta
Keyword(s):  
Rare Earth ◽  
Rare Earth Element ◽  
Water Depth ◽  
Upper Cretaceous ◽  
Earth Element ◽  
Small Sample Size ◽  
Small Sample ◽  
Depositional Environments ◽  
Marine Deposits ◽  
Taxonomic Groups

AbstractKnowledge of habitat segregation of mosasaurs has been based on lithology and faunal assemblages associated with fossil remains of mosasaurs and stable isotopes (δ13C). These approaches have sometimes provided equivocal or insufficient information and, therefore, the preference of habitat by different mosasaur taxa is still suboptimally constrained. The present study is focused on the analysis of rare earth element (REE) ratios of mosasaur fossils from the Upper Cretaceous formations of western Alabama, USA. Results of the REE analysis are used to infer the relative paleobathymetry associated with the mosasaur specimens and then to determine if certain taxonomic groups showed a preference for a particular water depth. Comparisons are then made with mosasaur specimens reported in the literature from other regions of North America from different depositional environments. Results indicate that Mosasaurus, Platecarpus and Plioplatecarpus may have preferred more restricted habitats based on water depth whereas Tylosaurus and Clidastes favoured a wider range of environments. Results also suggest that Plioplatecarpus lived in a shallower environment than its Platecarpus predecessor. Although the results of this study are encouraging, caution must be exercised before drawing any final conclusions due to the small sample size of most of the taxa analysed.

Massive High-Angle Normal Faulting at distal magma-poor margins: examples from South Atlantic

2020 ◽  
Author(s):  
Michaël Denis ◽  
Jean-François Ballard
Keyword(s):  
Evolutionary Model ◽  
South Atlantic ◽  
Depositional Environments ◽  
Moho Depth ◽  
Normal Faults ◽  
High Angle ◽  
Seismic Profiles ◽  
Salt Deposition ◽  
Field Evidence ◽  
Deformation Processes

<p>Seismic imaging of very distal margins enabled to evidence seaward-verging normal faults with slip displacements up to 6000 meters, in several areas of both African & Brazilian magma-poor margins.</p><p>Interpretation of deep seismic profiles, including 3D seismic, time- & depth-migrated, evidence sharp depth variations of the Moho, close to areas where subcontinental mantle exhumed further to successive activation of Low-Angle Normal Faults and large detachement faults.</p><p>The sharp Moho depth variations are related to giant High-Angle Normal Faults (HANF) which had offset the Moho itself and may have rooted close to the base of the serpentinized mantle. The faults are sealed within the salt, enabling to date it Late Aptian in age.</p><p>The close synchronicity between HANF activity and salt deposition reflects some dramatic changes of depositional environments, subsidence and deformation processes at the scale of the margin, especially as salt deposition is also closely related to significant increase of magmatic additions in the ultra-distal parts of the margin.</p><p>These changes are very likely related to the lithospheric break-up process and support the post-detachement timing of activation of the HANF interpreted from cross-cutting relationships on the seismics.</p><p>The evolutionary model for HANF proposed is supported by field evidence, seismic analogs and thermomechanical models: it invokes thermal, isostatic, rheologic, tectono-magmatic processes, and documents the context of South Atlantic salt deposition.</p>

Impact of depositional regimes on biogeochemical cycling of iron and stable Fe signatures in sediments from the Argentina Continental Margin

2020 ◽  
Author(s):  
Anne-Christin Melcher ◽  
Susann Henkel ◽  
Thomas Pape ◽  
Anette Meixner ◽  
Simone A. Kasemann ◽  
...  
Keyword(s):  
Continental Margin ◽  
Water Depth ◽  
Surface Sediments ◽  
Depositional Environments ◽  
Anaerobic Oxidation Of Methane ◽  
Sedimentation Rates ◽  
Biogeochemical Processes ◽  
High Sedimentation ◽  
Terrace Site ◽  
Fe Reduction

<p>The Argentina Continental Margin represents a unique geologic setting where fundamental interactions between bottom currents and sediment deposition as well as their impact on biogeochemical processes and element cycling, in particular iron, can be studied. The aims of this study were to investigate 1) the consequences of different depositional conditions on biogeochemical processes and 2) diagenetic cycling of Fe mineral phases in surface sediments. Furthermore, it was 3) studied how sedimentary stable Fe isotope signatures (δ<sup>56</sup>Fe) are affected during early diagenesis and finally 4) evaluated, under which conditions δ<sup>56</sup>Fe might be used as proxy for microbial Fe reduction in methanic sediments. During RV SONNE expedition SO260, carried out in the framework of the DFG-funded Cluster of Excellence “The Ocean in the Earth System”, surface sediments from two depositional environments were sampled each using gravity corer and multi corer. One study site is located on the lower continental slope at 3605 m water depth (Biogeochemistry Site), while the other site is situated in a contourite system on the Northern Ewing Terrace at 1078 m water depth (Contourite Terrace Site). Sequential Fe extractions were performed on the collected sediments to determine four operationally defined reactive Fe phases targeting Fe carbonates, (easily) reducible Fe (oxyhydr)oxides and hardly reducible Fe oxides [1]. Purification of extracts for δ<sup>56</sup>Fe analysis of the Fe carbonates and easily reducible Fe (oxyhydr)oxide fractions followed [2]. The dataset was combined with pore-water data obtained during the cruise and complemented by concentrations and stable carbon isotope signatures of dissolved methane determined post-cruise. The extent of the redox zonation and depth of the sulfate-methane-transition (SMT) differ between the two sites. It is suggested that sedimentation rates at the Biogeochemistry Site are low and that steady state conditions prevail, leading to a strong diagenetic overprint of sedimentary Fe phases. In contrast the Contourite Terrace Site is characterized by high sedimentation rates and a lack of pronounced diagenetic overprint [3]. Reactive Fe phases are subject to reductive dissolution at the SMT. Nevertheless, significant amounts of reactive Fe phases are preserved below the SMT as evidenced by the presence of dissolved Fe in the methanic sediments, and are available for deep Fe reduction possibly through Fe-mediated anaerobic oxidation of methane [4]. In this study, δ<sup>56</sup>Fe signatures of reactive Fe phases in methanic sediments were determined for the first time. These data suggest significant microbial fractionation of Fe isotopes during deep Fe reduction at the Biogeochemistry Site, whereas at the Contourite Terrace Site the δ<sup>56</sup>Fe signatures do not indicate remarkable microbial Fe isotope fractionation. It is concluded that the applicability of δ<sup>56</sup>Fe signatures as tracer for microbial Fe reduction might be sensitive to the depositional regime, and thus may be limited in high sedimentation areas.</p><p>References:<br>Poulton, SW. and Canfield, DE., 2005. <em>Chemical Geology</em> 214: 209-221.<br>Henkel, S. et al., 2016. <em>Chemical Geology</em> 421: 93-102.<br>Riedinger, N. et al., 2005. <em>Geochimica et Cosmochimica Acta</em> 69: 4117-4126.<br>Riedinger, N. et al., 2014. <em>Geobiology</em> 12: 172-181.</p>

scholarly journals Sedimentary facies, stratigraphy, and depositional environments of the Ecca Group, Karoo Supergroup in the Eastern Cape Province of South Africa

2021 ◽  
Vol 13 (1) ◽  
pp. 748-781
Author(s):  
Christopher Baiyegunhi ◽  
Kuiwu Liu
Keyword(s):  
South Africa ◽  
Water Depth ◽  
Facies Analysis ◽  
Sedimentary Facies ◽  
Depositional Environments ◽  
Eastern Cape Province ◽  
Eastern Cape ◽  
Borehole Data ◽  
Karoo Basin ◽  
Facies Associations

Abstract The stratigraphy of the Ecca Group has been subdivided into the Prince Albert, Whitehill, Collingham, Ripon, and Fort Brown Formations in the Eastern Cape Province, South Africa. In this article, we present detailed stratigraphic and facies analyses of borehole data and road-cut exposures of the Ecca Group along regional roads R67 (Ecca Pass), R344 (Grahamstown-Adelaide), R350 (Kirkwood-Somerset East), and national roads N2 (Grahamstown-Peddie) and N10 (Paterson-Cookhouse). Facies analysis of the Ecca Group in the study area was performed to deduce their depositional environments. Based on the lithological and facies characteristics, the stratigraphy of the Prince Albert, Whitehill, Collingham, and Fort Brown Formations is now subdivided into two informal members each, while the Ripon Formation is subdivided into three members. A total of twelve lithofacies were identified in the Ecca Group and were further grouped into seven distinct facies associations (FAs), namely: Laminated to thin-bedded black-greyish shale and mudstones (FA 1); Laminated black-greyish shale and interbedded chert (FA 2); Mudstone rhythmite and thin beds of tuff alternation (FA 3); Thin to thick-bedded sandstone and mudstone intercalation (FA 4); Medium to thick-bedded dark-grey shale (FA 5); Alternated thin to medium-bedded sandstone and mudstone (FA 6); and Varved mudstone rhythmite and sandstone intercalation (FA 7). The FAs revealed gradually change of sea-level from deep marine (FA 1, FA 2, FA 3 and FA 4, FA 5, and FA 6) to prodelta environment (FA 7). This implies that the main Karoo Basin was gradually filling up with Ecca sediments, resulting in the gradual shallowing up of the water depth of the depositional basin.

scholarly journals Monitoring Atmospheric Aerosols Over the Urmia Lake by CALIPSO and a Ground Based Depolarized Lidar

2020 ◽  
Vol 237 ◽  
pp. 02025
Author(s):  
Hamid R. Khalesifard ◽  
Hossein Panahifar ◽  
Fatemeh Ghomashi ◽  
Salar Alizadeh ◽  
Ruhollah Moradhaseli
Keyword(s):  
Boundary Layer ◽  
Atmospheric Boundary Layer ◽  
Aerosol Optical Depth ◽  
Optical Depth ◽  
Atmospheric Aerosols ◽  
Urmia Lake ◽  
Hypersaline Lake ◽  
Depolarization Ratio ◽  
Hysplit Model ◽  
Aerosol Source

The Urmia Lake, a hypersaline lake in Northwest Iran is facing a severe drying scenario. We have installed an azimuthal scanning depolarized backscatter lidar in the coast of the lake to monitor the atmospheric aerosols that may originate from the dried lake bed. We also used the CALIPSO recordings to monitor the aerosol optical depth and particulate depolarization ratio just over the lake. Recordings of the lidar and CALIPSO both show that dry salt particles can be found in the atmospheric boundary layer over the lake especially in summer times. Also CALIPSO data in synergy with HYSPLIT model show that the lake is not an intense aerosol source comparing to neighboring sources like the Mesopotamia region but it is under their influence.

scholarly journals New record of three freshwater fish species from a western drainage of Lake Urmia for the Turkish fauna

2020 ◽  
Vol 37 (4) ◽  
pp. 325-328
Author(s):  
Cüneyt Kaya
Keyword(s):  
Freshwater Fish ◽  
Fish Species ◽  
New Record ◽  
Urmia Lake ◽  
Hypersaline Lake ◽  
Lake Urmia ◽  
Freshwater Fish Species

In the scope of this study, three freshwater fish species were newly recorded for Turkey from a western drainage of Lake Urmia: Alburnoides petrubanarescui, Alburnus atropatenae and Oxynoemacheilus elsae. All of them were found in headwaters of Nazli-chay River in the basin of the hypersaline Lake Urmia. The Lake is fed by many small springs and thirteen permanent rivers. In the previous studies, the existence of a stream in the western part of the Urmia Lake within border of Turkey was not mentioned.

Sign in / Sign up

Export Citation Format

Share Document