Petrographic and geochemical features of Gimo marble, Gole area, Kurdistan Region, Iraq: constraints on its protolith's origin and depositional environment

It is essential to identify marbles' petrographic and geochemical characteristics to determine the palaeo-environmental settings where their carbonate protoliths formed. The petrogenesis of massive Gimo marbles in the Gole area, Kurdistan Region of northeast Iraq, was investigated in this study through a combination of field mapping, petrographic, and geochemical techniques. Petrographic examination of these marbles reveals that mineral compositions are similar in all samples, with both homeoblastic and mosaic textures occurring, in addition to opaque grains that provide evidence of mineralization. Geochemical analyses show that the average calcium carbonate content of the marble is 94.96%; hence, the marble is lithologically characterized as a pure calcite marble. In most samples, the silica content was below 2 wt.%, with high values related to quartz veinlets. A range of geochemical indices and Post-Archean Australian Shale (PAAS–normalized rare earth element (REE) patterns) suggest that the limestone protolith was deposited in a shallow, near-shore marine environment on a continental margin, with very low input of detrital material. The negative Ce anomalies indicate that the protoliths of the Gimo marbles were carbonate rocks of a sedimentary origin.

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An organic Geochemical analysis of Terrestrial biomarkers in a transect of the Great Barrier Reef Lagoon

Marine and Freshwater Research ◽

10.1071/mf9890275 ◽

1989 ◽

Vol 40 (3) ◽

pp. 275 ◽

Cited By ~ 16

Author(s):

BR Currie ◽

RB Johns

Keyword(s):

Great Barrier Reef ◽

Barrier Reef ◽

Terrestrial Organic Matter ◽

Higher Plant ◽

Pentacyclic Triterpenoid ◽

Lipid Biomarker ◽

Additional Input ◽

Near Shore ◽

Benthic Sediments ◽

Geochemical Analyses

Organic geochemical analyses of benthic sediments from a Northern Queensland coastal transect indicate that most terrestrial organic material is confined to near-shore sediments (<10 km offshore). Traces of higher plant material reach the inner fringes of the Great Barrier Reef, as indicated by the presence of pentacyclic triterpenoid alcohols (PTA) in near-reef sediments. A likely source of these alcohols is mangroves. PTA and long-chain normal alkanes appear to be the most reliable of the lipid biomarker classes analysed in assessing the distribution of terrestrial organic matter along the transect. Other terrestrial biomarker classes (sterols, normal fatty acids and fatty alcohols) present in the sediment do not show good correlation with distance from the land. This is believed to be due to the additional input of these biomarkers from planktonic sources.

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Selected Grain-Size and Geochemical Analyses of the Loess-Paleosol Sequence of Pécel (Northern Hungary): An Attempt to Determine Sediment Accumulation Conditions and the Source Area Location

Quaternary ◽

10.3390/quat4020017 ◽

2021 ◽

Vol 4 (2) ◽

pp. 17

Author(s):

László Makó ◽

Dávid Molnár ◽

Boglárka Runa ◽

Gábor Bozsó ◽

Péter Cseh ◽

...

Keyword(s):

Composition Studies ◽

Sediment Accumulation ◽

Source Area ◽

Sufficient Information ◽

Source Areas ◽

Sulphide Minerals ◽

The Past ◽

Geochemical Indices ◽

Geochemical Analyses ◽

Buda Thermal Karst

The loess-paleosol profile near the settlement of Pécel has a notable size among the loess-paleosol sequences of the Northern Carpathian territories. Therefore, comprehensive sedimentological examinations were performed to understand the profile and the information preserved in it. The past periodicity and intensity of winds were showed by particle composition studies (GSI, U-ratio). At least two source areas can be presumed based on geochemical indices (CIA, CIW, Rb/Sr, Zr/Rb). Based on the characteristics of the chemical composition of sulphide minerals (P, S, Pb, Ni, As sulphides), the lower 10 m of the profile was supposed to be transported from the NW direction (Buda Thermal Karst, Börzsöny, Cserhát). Sufficient information is not yet available in order to determine the source area of the upper 10 m. By using the mentioned indexes, major developing and weathering horizons also could be identified.

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GEOLOGICAL CONTROLS ON SONIC VELOCITY IN THE CENOZOIC CARBONATES OF THE NORTHERN CARNARVON BASIN, NORTH WEST SHELF, WESTERN AUSTRALIA

The APPEA Journal ◽

10.1071/aj02020 ◽

2003 ◽

Vol 43 (1) ◽

pp. 385 ◽

Cited By ~ 8

Author(s):

M.W. Wallace ◽

E. Condilis ◽

A. Powell ◽

J. Redfearn ◽

K. Auld ◽

...

Keyword(s):

Large Scale ◽

Submarine Canyon ◽

Carbonate Content ◽

Sonic Velocity ◽

North West ◽

Geological Processes ◽

Near Shore ◽

Marine Facies ◽

Calcite Cementation ◽

Northern Carnarvon Basin

The Cenozoic carbonates of the Bounty-Talisman region can be divided into five major facies. From oldest to youngest, these are: Paleocene to Eocene basinal facies, Oligocene to Miocene slope-canyon facies, Oligocene to Miocene shelf facies, Oligocene to Miocene near-shore facies, and Pliocene-Quaternary shelf facies. This represents a shallowing-upwards cycle up to the late Miocene, followed by a significant transgression and a return to more open marine conditions in the Pliocene- Quaternary. The dominant geological processes controlling sonic velocity in the Cenozoic carbonates are physical compaction, burial calcite cementation, dolomitisation, and anhydrite/gypsum cementation. In the more open marine facies of the Cenozoic carbonates, compaction and burial calcite cementation have been the dominant geological processes that have controlled sonic velocity. Large-scale carbonate content variations associated with submarine canyon-fill sediments have also produced lateral sonic velocity variations. Dolomitisation and anhydrite cementation have produced localised high velocity zones within the near-shore facies of the carbonates.

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The Influence of Olive Orchards Copper-Based Fungicide Use, in Soils and Sediments—The Case of Aetoliko (Etoliko) Lagoon Western Greece

Geosciences ◽

10.3390/geosciences9060267 ◽

2019 ◽

Vol 9 (6) ◽

pp. 267

Author(s):

Pavlos Avramidis ◽

Pantelis Barouchas ◽

Thomas Dünwald ◽

Ingmar Unkel ◽

Dionisios Panagiotaras

Keyword(s):

Copper Content ◽

Threshold Value ◽

Carbonate Content ◽

Toxicity Screening ◽

Average Value ◽

Total Copper ◽

Soils And Sediments ◽

Total Digestion ◽

Lagoon Sediments ◽

Geochemical Analyses

In this study, soil and aquatic sediments were sampled in the Aetoliko Lagoon and its catchment area, which is exclusively dominated by olive orchards. For the first time in Greece, soil as well as sediments samples of one coherent protected aquatic ecosystem were directly compared. In order to determine the influence that the usage of copper-based fungicides have on the lagoon sediments and on the soils of the surrounding area, twenty five (25) soil samples from different olive orchards that are bordering the water body and ten (10) sediment samples from the bottom of the lagoon were taken. The samples were analyzed for total copper content (total digestion) and extractable copper (diethylenetriaminepenta acetic acid, DTPA, extraction method). Furthermore, soil/sedimentological and geochemical analyses such as pH, grain size, total organic carbon, total sulfur, total nitrogen, and calcium carbonate content were carried out. The results show that the total copper in soils ranges from 58.37 to 671.33 mg kg−1. In addition the DTPA-extractable copper in soils has an average value of 45.00 mg kg−1. The average value of total copper in soils (286.24 mg kg−1) is higher than the threshold value for the Cu concentration (100 mg kg−1) set by the EU countries. Total copper content in the lagoon sediments is lower than in soils and varies between 43.85 mg kg−1 and 71.87 mg kg−1. The DTPA-extractable copper in sediments is in low ranges from 0.14 to 0.60 mg kg−1. On average, the total copper value for the lagoon sediments (55.93 mg kg−1) exceeds the Toxicity Screening Value (25.20 mg kg−1) for Cu in freshwater sediments. From the present study, it is clear that, although the copper in soils of the surrounding lagoon area exceeds the threshold limit for ecological risk, the lagoon sediments are influenced in a smaller degree. Our study can be used as a valuable reference and baseline for future studies on the environmental monitoring of the Aetoliko lagoon, as well as for studies in similar ecosystems.

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The Eutrophication Problem

Journal of the Fisheries Research Board of Canada ◽

10.1139/f72-113 ◽

1972 ◽

Vol 29 (6) ◽

pp. 673-682 ◽

Cited By ~ 59

Author(s):

A. M. Beeton ◽

W. T. Edmondson

Keyword(s):

Lake Michigan ◽

Nutrient Loading ◽

Silica Content ◽

Nitrogen And Phosphorus ◽

Large Lakes ◽

Western Basin ◽

Nitrogen Concentrations ◽

Near Shore ◽

Morphology And Morphometry ◽

Lake Waters

The trophic state of a lake is maintained by continued inputs of nutrients. In very large lakes the inshore environments are affected first by increased nutrient loading and, depending upon the morphology and morphometry, gradually the offshore waters are altered. The near-shore waters of Lake Michigan have greater concentrations of nitrogen and phosphorus and a lower silica content than open lake waters. Diatoms are more abundant inshore than offshore, the doubling times for diatom populations are shorter inshore, and species favored by nutrient-rich conditions are more abundant inshore. Data on plankton, nitrogen concentrations, and fish, from early studies on Lake Erie, show progressive changes from the shore lakeward and from the western basin eastward.

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Geochemical characteristics of Upper Jurassic – Lower Cretaceous platform carbonates in Hazine Mağara, Gümüşhane (northeast Turkey): implications for dolomitization and recrystallization

Canadian Journal of Earth Sciences ◽

10.1139/cjes-2018-0168 ◽

2019 ◽

Vol 56 (3) ◽

pp. 306-320 ◽

Cited By ~ 3

Author(s):

Merve Özyurt ◽

M. Ziya Kırmacı ◽

Ihsan S. Al-Aasm

Keyword(s):

Lower Cretaceous ◽

Carbonate Platform ◽

Upper Jurassic ◽

Close Proximity ◽

Post Archean Australian Shale ◽

History Of ◽

Polymetallic Mineralization ◽

Platform Carbonates ◽

Geochemical Studies ◽

Ree Patterns

The Upper Jurassic – Lower Cretaceous Berdiga Formation of the Eastern Pontides, Turkey, represents a carbonate platform succession composed of pervasively dolomitized intra-shelf to deep-shelf facies. In this area, polymetallic deposits occur as veins and lenses within the Berdiga Formation in close proximity to its upper contact with the overlying formation. Three different types of replacive dolomites occur in the formation: (i) microcrystalline dolomite, (ii) fabric-preserving dolomite, and (iii) fabric-destructive dolomite. Replacive dolomites are Ca rich and nonstoichiometric (Ca56–58Mg42–44) and are characterized by a pronounced negative shift in oxygen (–11.38‰ to –4.05‰ Vienna Pee Dee Belemnite (VPDB)), δ13C values of 0.69‰ to 3.13‰ VPDB, radiogenic 87Sr/86Sr ratios (0.70753 to 0.70884), and extremely high Fe (2727–21 053 ppm) and Mn (1548–27 726 ppm) contents. All dolomite samples have low Y/Ho ratios (23–40), and they also contain highly variable contents of rare earth elements (REE) (7–41). REE patterns of dolomites normalized to Post-Archean Australian shale show a distinct positive Eu anomaly (1.3–2.1) and slightly flattened Ce anomalies (0.8–1.1). Integration of petrographic and geochemical studies reveals the history of a variety of diagenetic processes highly affected by hydrothermal alteration, which include dolomitization, recrystallization, dissolution, silicification, and pyrite mineralization associated with the emplacement of the polymetallic mineralization.

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Formation And Development of Vertisols in Selivany Plain at Duhok Governorate, Kurdistan Region, Iraq

The Journal of The University of Duhok ◽

10.26682/ajuod.2020.23.2.28 ◽

2020 ◽

Vol 23 (2) ◽

pp. 246-258

Author(s):

Haliz Darwish Abdulrahman ◽

Mohammed Ali Fayyadh ◽

Jamal A.h. Doski

Keyword(s):

Organic Matter ◽

Clay Content ◽

Parent Material ◽

Soil Samples ◽

Plant Roots ◽

Carbonate Content ◽

Kurdistan Region ◽

Standard Methods ◽

Total Carbonate ◽

Pedogenic Processes

The study area located at the Selivany plain in Duhok governorate, Kurdistan Region, Iraq. Forty- three soil samples were taken from horizons in all studied pedons then physically and chemically analyzed according to standard methods. The studied soils were slightly alkaline non- saline. The values of CEC increased with increasing clay content. The Studied soils considered Vertisols and occurs pedoturbation, in turn, trans-locating organic matter from surface to subsurface and deep horizons, additionally, existing plant roots contribute in increasing organic matter in these horizons, and the humification process can occur in different soil horizons. Total carbonate content increased with increasing depth in subsurface horizons this due to the origin of limestone parent materials. The differences in carbonate distribution manner indicated to development. The studied soils contain a considerable amount of active carbonate that affecting different soil properties. Relatively high clay content in studied soils and its content at the surface horizons are lower than it at subsurface horizons. The high value of clay and silt content indicates to soil development. The following pedogenic processes can be specified loss, gain, leaching, illuviation, eluviation, alkalization, humification, lessivage, desalinization, calcification, decomposition, synthesis, pedoturbation, and braunification. Humification processes of organic matter are predominate because the ratio of carbon to nitrogen (C / N) is less than 25. According to the criterion (Total clay in B-horizon / Total clay at A-orizon) most of the studied pedons (1, 3, 6, 7, 8, 9, 10, 12, 13, and 14) considered as well developed soils. The ratio of (Active carbonate/ Total carbonate) was high ranged between (0.31-3.14%), and this may be due to the high weathering intensity of parent material, as a result of increased the ratio mass of active carbonate to total carbonate.

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Carbonate Beach Sand of Abaiang Atoll, Kiribati: Geochemistry, Biogenic Sources, and Properties

Atoll Research Bulletin ◽

10.5479/si.0077-5630.621 ◽

2019 ◽

pp. 1-21

Author(s):

Joanna C. Ellison ◽

Paul Han ◽

Trevor W. Lewis

Keyword(s):

Calcium Carbonate ◽

Magnesium Carbonate ◽

Sandy Beaches ◽

Beach Sand ◽

Carbonate Content ◽

Beach Sediment ◽

Longshore Drift ◽

Sand Supply ◽

Significant Difference ◽

Near Shore

Sandy beaches are critical resources for low-lying Pacific atoll communities, providing protection during storms, and land area for many coastal villages. Information on the nature of atoll beach sediment, its geochemistry and composition, can help to establish priorities to effectively protect the sources of Pacific island beach sediment. To understand sand sources, this study evaluated its physical characteristics including grain-size, geochemistry and composition, from windward and leeward beach profiles around Abaiang Atoll, Kiribati. Beach sand was >99% carbonate, averaging 37% coral fragments, 30% mollusc shells, 12% foraminifera, and 20% calcareous algae. Significant differences were found between reef and lagoonal sites in proportions of coral and mollusc fragments and foraminifera tests, with lagoon beaches having higher mollusc and coral proportions and lower foraminifera relative to reef beaches. This is attributed to high foraminiferal productivity offshore of reef beaches, and taphonomic durability of coral fragments in longshore drift into the lagoon. Mean sediment diameter increased from the upper to lower beaches at all sites, but fine sediment was lacking, attributed to its dissolution by rainfall and groundwater outflow. Geochemical analysis showed a mean of 84% Ca-Mg carbonates, of which 80% was calcium carbonate. There was no significant difference in the mean calcium percentage or calcium carbonate composition of the sediment between lagoon and reef beach sediment sources. Magnesium and magnesium carbonate content were significantly higher at reef sites relative to lagoon sites, attributed to higher proportions of foraminifera. Sediment-producing near shore habitats are critical to village protection through provision of beach sand, and this study shows the need to better conserve and manage coral reefs and habitats such as lagoon seagrass beds, to ensure continued atoll beach sand supply.

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Particulate Rare Earth Element behavior in the North Atlantic (GEOVIDE cruise)

10.5194/bg-2019-462 ◽

2020 ◽

Cited By ~ 1

Author(s):

Marion Lagarde ◽

Nolwenn Lemaitre ◽

Hélène Planquette ◽

Mélanie Grenier ◽

Moustafa Belhadj ◽

...

Keyword(s):

Rare Earth ◽

North Atlantic ◽

Iron Hydroxides ◽

Ce Anomaly ◽

The North ◽

Post Archean Australian Shale ◽

The North Atlantic ◽

Diatom Blooms ◽

Ree Patterns ◽

Iberian Margin

Abstract. Particulate concentrations of the fourteen Rare Earth Elements (PREE), yttrium and 232-thorium have been measured in two hundred samples collected in the epipelagic (ca. 0–200 m) and the mesopelagic (ca. 200–1000 m) zones of the North Atlantic, during the GEOVIDE cruise (May/June 2014, R/V Pourquoi Pas ?, GEOTRACES GA01). Particulate cerium (PCe) concentrations vary from 0.2 pmol L−1 to 16 pmol L−1, particulate neodymium (PNd) ones from 0.09 pmol L−1 to 6.1 pmol L−1 and particulate ytterbium (PYb) ones from 0.01 pmol L−1 to 0.5 pmol L−1. PREE concentrations are higher close to the Iberian margin and on the Greenland shelf, where PREE concentrations normalized to Post Archean Australian Shale (PAAS) display a positive Ce anomaly between 0.3 and 3, and a light REE (LREE) enrichment compared to heavy REE (HREE) illustrated by high PNdN/PYbN ratios (normalized to PAAS). The lithogenic fraction of the particulate REE concentration is closely related to the margin morphology and the hydrodynamic context: off the Iberian margin, up to 100 % of the PREEs are lithogenic and this lithogenic input spreads westward along isopycnals as intermediate nepheloid layers (INL) up to 1700 km away. Lithogenic inputs are also observed along the Greenland and Newfoundland margins, although the circulation stacks them along the coasts. PREE distributions are also controlled by the biological uptake in the surface layers and remineralization processes deeper. Low surface concentrations and some normalized REE patterns displaying a negative Ce anomaly and HREE enrichment indicate freshly formed biogenic particles. A significant relationship between biogenic silica (BSi) and PHREE is also observed in the diatom blooms occurring in the Labrador and Irminger seas. PHo/PY ratio was calculated in order to identify processes independent of the ionic radius. However, we could not firmly assess the role of the iron hydroxides in the scavenging prates of these elements.

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SPECTROPHOTOMETRY ANALYSIS OF DEEP-SEA SEDIMENTS ALONG THE MAIN PATHYWAY OF THE INDONESIAN THROUGHFLOW: SPATIAL VIEW

Marine Research in Indonesia ◽

10.14203/mri.v41i2.115 ◽

2016 ◽

Vol 41 (2) ◽

pp. 51-58

Author(s):

Intan Suci Nurhati

Keyword(s):

Deep Sea ◽

Xrd Analysis ◽

Carbonate Content ◽

Indonesian Throughflow ◽

Deep Sea Sediment ◽

Visible Spectra ◽

Spatial View ◽

Past Climate Change ◽

Geochemical Analyses ◽

Derivatives Of

Deep-sea sediment is the primary marine archive for reconstructing climate of the past millennia. With an array of geochemical analyses and more techniques to be developed, conservative sample usage is necessary. This study presents spectrophotometry analysis as a non-intrusive approach on deep-sea sediment samples retrieved along the main pathway of the Indonesian Throughflow in the Makassar Strait. Sediments from 25 sites including: Eastern Kalimantan, western Sulawesi, south Makassar Strait, southern Sulawesi and northern Bali are scanned as wet and dried samples over the visible spectra (400-700nm). After taking first derivatives of the raw data to accentuate the signals, R-mode factor analysis is applied to reveal three factors that explain 96.99% variance. Factor 1, which explains 53.94% variance, is characterized as halite. Factor 2 (30.89%) is carbonate and Factor 3 (12.18%) is kaolinite or clay mineral. XRD analysis reveals the presence of calcite, quartz, halite, plagioclase and aragonite, with the first three being the most prevalent minerals. Spatial distribution map of Factor 1 (halite) shows higher values in eastern Kalimantan, south Makassar Strait and western Sulawesi. Factor 2 (carbonate) is relatively high in eastern Kalimantan, southern Sulawesi and northern Bali; with similar observation at the first two sites from accompanying carbonate content analysis. Relatively high Factor 3 (kaolinite) in eastern Kalimantan is consistent with its proximity to the Mahakam River delta. Characteristics of each region are further discussed herein. Taken together, this information lays a foundation for applying the non-intrusive spectrophotometry downcore to study past climate change in the Makassar Strait.

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