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The identification and quantification of aeolian sand contributions are essential for understanding the formation of dune fields and mechanisms of modern surface processes. In the present study, we take aeolian sand in the Otindag dune field (hereafter, often referred to as, simply, Otindag) as the research object. The dune field's immediate source is quantitatively identified based on heavy minerals and the Conservativeness Index (CI), Consensus Ranking (CR), and the Consistent Tracer Selection (CTS) method. The primary source area of the aeolian sand was found to be from the northwestern, upwind area of the Otindag (59 ± 14%), followed by the Yinshan Mountain (17 ± 10%) and the lake basin (23 ± 12%). The proposed sediment transport model elucidates that sediments from the upwind of the Otindag are directly transported from the northwest to the Otindag, where they are deposited. Materials from the southern Yinshan Mountains are carried by rivers to the southern edge of the Otindag, where they are subsequently transported by wind and ultimately deposited. The lake deposits within the Otindag also contribute to the aeolian sand supply under the influence of wind. This study demonstrates that the fingerprinting techniques of CI, CR, and CTS serve as successful strategies for conducting quantitative provenance research in dune fields. [ABSTRACT FROM AUTHOR]

Hódmezővásárhely–Gorzsa is a multi-period tell settlement in South Hungary in the centre of the Great Hungarian Plain, about 15 km southwest of the city of Hódmezővásárhely. The thickest section of the settlement belongs to the Late Neolithic Tisza Culture period. In total, 1061 macrolithic artefacts were unearthed, a quarter of which was polished, and three quarter of which were ground stone tools. Half of the ground stones were made of different types of sandstone, including (1) red-, (2) grey micaceous-, (3) calcareous-, (4) white meta sandstones, and (5) other sandstones and metasandstones were identified. The red sandstones are further categorised into four subgroups based on optical microscopy. This examination is the first systematic multi-analytical investigation (i.e. optical microscopy, whole-rock geochemistry and mineral chemistry), carried out on these ground stone tool types. The goal is to identify and precisely locate the raw material types, in which heavy minerals and the tourmaline mineral chemistry play the key role. To determine the provenance of each of these subgroups, samples were collected from seven geological localities (i.e. primary outcrops and secondary presences, such as river drainages or terraces) for a comparative study. Based on our results, the alluvium of the Maros River can be considered as a possible source for the ‘Red – 3’ type of Gorzsa, while the results for the rest red sandstone types (‘Red – 1’, ‘Red − 2’ and ‘Red – 4’) are inconclusive in terms of provenance. [ABSTRACT FROM AUTHOR]

Acceptable zircon for composite formulation in the aerospace industry requires that the mineral contains a minimum of 65% zirconia (ZrO2). Despite having vast deposits of zircon, Nigeria's aerospace industry has historically relied primarily on imported mild steel tubes for solid rocket motor cases (SRMCs) construction, resulting in three major challenges: low strength-to-weight ratio, pressure, and temperature containment. In this study, the Arikya zircon deposit located in northern Nigeria was investigated with the aim of upgrading low-grade zircon ore using magnetic and gravity separation processes for use in composite formulation for SRMCs. The dry high-intensity magnetic separator (DHIMS) produced a ZrO2 grade of 52.48%, recovery of 57.99%, and an enrichment ratio of 0.78 with a separation efficiency of 0.56, while the air-floating separator (AFS) generated the highest of 65.52% ZrO2 grade with 70.81% recovery and enrichment ratio of 1.25 with a separation efficiency of 0.25. The ZrO2 content increased from 40.77 to 65.52% after beneficiation. Iron oxide and titanium dioxide contaminants at 0.73 and 0.83% were reduced to 0.66 and 0.54%, respectively, while the specific gravity increased from 4.4 to 4.6 g/cm3. The ZrO2 content and specific gravity were improved to the minimum standard specified for zirconia-reinforced composite application and competed effectively with industrially/globally accepted zircon. These results demonstrated the efficacy of combining DHIMS and AFS to upgrade the low-grade zircon ore from Arikya, Nasarawa State. [ABSTRACT FROM AUTHOR]

Acceptable zircon for composite formulation in the aerospace industry requires that the mineral contains a minimum of 65% zirconia (ZrO2). Despite having vast deposits of zircon, Nigeria’s aerospace industry has historically relied primarily on imported mild steel tubes for solid rocket motor cases (SRMCs) construction, resulting in three major challenges: low strength-to-weight ratio, pressure, and temperature containment. In this study, the Arikya zircon deposit located in northern Nigeria was investigated with the aim of upgrading low-grade zircon ore using magnetic and gravity separation processes for use in composite formulation for SRMCs. The dry high-intensity magnetic separator (DHIMS) produced a ZrO2 grade of 52.48%, recovery of 57.99%, and an enrichment ratio of 0.78 with a separation efficiency of 0.56, while the air-floating separator (AFS) generated the highest of 65.52% ZrO2 grade with 70.81% recovery and enrichment ratio of 1.25 with a separation efficiency of 0.25. The ZrO2 content increased from 40.77 to 65.52% after beneficiation. Iron oxide and titanium dioxide contaminants at 0.73 and 0.83% were reduced to 0.66 and 0.54%, respectively, while the specific gravity increased from 4.4 to 4.6 g/cm3. The ZrO2 content and specific gravity were improved to the minimum standard specified for zirconia-reinforced composite application and competed effectively with industrially/globally accepted zircon. These results demonstrated the efficacy of combining DHIMS and AFS to upgrade the low-grade zircon ore from Arikya, Nasarawa State.

The identification and quantification of aeolian sand contributions are essential for understanding the formation of dune fields and mechanisms of modern surface processes. In the present study, we take aeolian sand in the Otindag dune field (hereafter, often referred to as, simply, Otindag) as the research object. The dune field’s immediate source is quantitatively identified based on heavy minerals and the Conservativeness Index (CI), Consensus Ranking (CR), and the Consistent Tracer Selection (CTS) method. The primary source area of the aeolian sand was found to be from the northwestern, upwind area of the Otindag (59 ± 14%), followed by the Yinshan Mountain (17 ± 10%) and the lake basin (23 ± 12%). The proposed sediment transport model elucidates that sediments from the upwind of the Otindag are directly transported from the northwest to the Otindag, where they are deposited. Materials from the southern Yinshan Mountains are carried by rivers to the southern edge of the Otindag, where they are subsequently transported by wind and ultimately deposited. The lake deposits within the Otindag also contribute to the aeolian sand supply under the influence of wind. This study demonstrates that the fingerprinting techniques of CI, CR, and CTS serve as successful strategies for conducting quantitative provenance research in dune fields.

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It is generally believed that the provenance of the Neogene sandbar reservoir in the Zhahaquan Oilfield in the western Qaidam Basin is consistent with that of the Paleogene. However, existing studies present different opinions on the provenance during the Paleogene, which makes the provenance of the Neogene unclear and affects the study of sedimentary facies and reservoir configuration in the Zhahaquan area. By using SPSS software, clustering analysis was conducted on the limited heavy mineral data from Neogene in this area.Then, the distribution characteristics of heavy minerals from different samples were studied and compared with the Tiemulik provenance and Qimantag-Dongchaishan provenance.It is considered that the Neogene provenance in the Zhahaquan area originated from Qimantag-Dongchaishan, and there is no evidence of intersection and mixing of the two major provenances. The Qimantag-Dongchaishan provenance can be further divided into two secondary provenances, i.e.one covering only the Zha2 well area, Zha401 well area and Zha7 well area, and the other covering the whole area. There is intersection and mixing of the two secondary provenances. This study clarifies the provenance of Neogene deposits in the Zhahaquan area and provides a significant reference for research on sandbar configuration, especially the migration and superposition of sandbars in this area.

The quantitative analysis of sediment sources in a sink is an important scientific topic and challenge in provenance research. The characteristics of heavy minerals, combined with the geochemical constituents of detrital grains, provide a reliable provenance-tracing approach. We developed a mineral identification method to analyze the multiple grain-size fraction of sediments, from which the elemental geochemistry of hornblende was used to compare the characteristics of sediments from the Huaihe River and Huanghe (Yellow) River in eastern China. Elements that were statistically identified as being able to discriminate sediment provenance were employed to perform a quantitative analysis of the sources of sediments of the abandoned Huanghe River. Results reveal that the Huaihe River is characterized by a high amphibole content of >60% and that the Huanghe and abandoned Huanghe rivers have greater abundances of limonite and carbonate minerals compared with those of the Huaihe River. The contents of trace elements and rare earth elements in hornblende show that the sediments of the abandoned Huanghe River are similar to those of the Huanghe River but different from those of the Huaihe River. Furthermore, chemical mass balance was used to calculate the relative contributions of different provenances of sediment from the abandoned Huanghe River, and nine trace elements of hornblende were identified as discriminators of provenance. Approximately 2% of the hornblende in the abandoned Huanghe River is derived from the Huaihe River and 98% from the Huanghe River. Considering the proportion of hornblende in the total sediment, it is inferred that the contribution of Huaihe River sediment to the abandoned Huanghe River is approximately 0.5%. This study shows that mineral analysis using multiple grain-size fractions (within the wide range of 1Φ to 6Φ) with assessment in elemental geochemistry of hornblende can characterize the provenance of fluvial material in coastal zones. [ABSTRACT FROM AUTHOR]

The study area includes sand bars carried by the Jamuna River, coastal dunes on Sonadia Island, and the beach sands of the island of Saint Martin's, all of which are geomorphologically distinct and possibly rich in economically valuable minerals. This study conducted for the first time in Bangladesh to investigate the occurrence of a few RREs such as Ce, La, Th, Zr, and Nd in monazite, zircon, and allanite heavy minerals. SEM–EDS, statistical methods, and heavy mineral analyses were used to determine the existence and significance of REEs in beach and river sand samples. The concentrations of Ag, La, Ce, and Th in the investigated grains of monazite (-Ce) varied, showing an asymmetric distribution, with the MANOVA test indicating statistically significant (p-value = 0.004) differences. Three primary components described almost 84% of all changes in monazite, and zircon on the other hand has a constant Zr content. The MANOVA test result shows that differences in zircon locations on two separate elements are statistically significant (p-value = 0.091). The existence of three rare earth elements (La, Ce, and Nd) in three places has been confirmed by allanite (-Ce), a REE-rich epidote mineral. According to the MANOVA test statistic, differences in allanite mineral study areas on three separate rare elements are not statistically significant (p-value = 0.245). The analytical data will help differentiate and characterize the REE-containing mineral grains in the diverse geological settings across Bangladesh. [ABSTRACT FROM AUTHOR]

Source‐to‐sink system studies in oil fields are especially important for optimizing the favourable oil‐gas areas; however, this basin‐mountain interaction process is particularly complicated in intermontane basins. In this study, detrital zircon U–Pb dating of 8 new and 3 published samples from throughout the Jurassic in the central Turpan Basin (TB) are combined with collected heavy mineral data to investigate the evolution of the source‐to‐sink system and reconstruct the filling process of this intermontane basin from the Lower to Upper Jurassic. Based on the detrital zircon ages and heavy mineral assemblage, the filling rocks mainly weathered from Mesozoic, Palaeozoic and Precambrian volcanic and metamorphic rocks in the Tian Shan (TS) area, and the source‐to‐sink systems in the basin show a clear alteration corresponding to the uplift of the surrounding mountains during the Jurassic. In the Lower Jurassic, the uplifted central and northern TS was the main provenance and shed the most source rocks northward, and the gentle positive relief of the Bogda Mountains (BM), the northern boundary of the TB, was a secondary provenance and provided limited material to the northern area. In the early Middle Jurassic, these provenances did not alter much, but in the later Middle Jurassic, uplift of the western BM began and provided some extreme new source rocks with detrital zircon ages of approximately 159–172 Ma. In the Upper Jurassic, the considerably uplifted BM became the main provenance, while the still gently uplifted central and northern TS became the secondary provenance. [ABSTRACT FROM AUTHOR]

Abstract Deep‐water depositional systems are the ultimate sink for vast quantities of terrigenous sediment, organic carbon and anthropogenic pollutants, forming valuable archives of environmental change. Our understanding of the distribution of these particles and the preservation of environmental signals, in deep‐water systems is limited due to the inaccessibility of modern systems, and the incomplete nature of ancient systems. Here, the deposit of a physically modelled turbidity current was sampled (n = 49) to determine how grain size and grain type vary spatially. The turbidity current had a sediment concentration of 17%. The sediment consisted of, by weight, 65% quartz sand (2.65 g/cm3), 17.5% silt (2.65 g/cm3), 7.5% clay (2.60 g/cm3) and 5% each of sand‐grade garnet (3.90 g/cm3) and microplastic fragments (1.50 g/cm3). The grain size and composition of each sample was determined using laser diffraction and density separation, respectively. The results show that: (a) bulk grain size coarsened axially downstream on the basin floor challenging the notion that basin floor deposits fine radially from an apex upon becoming unconfined; (b) no sample composition matched the input composition of the flow, indicating that allogenic signals can be autogenically shredded and spatially variable in sediment gravity flow deposits; and (c) microplastic fragments were concentrated in levee and lateral basin floor fringe positions; however, microplastic concentrations in these positions were lower than input, suggesting microplastics bypassed the sampled positions. These findings have implications for: (a) the development of ‘finger‐like’ geometries and facies distributions observed in modern and ancient systems; (b) interpreting environmental signals in the stratigraphic record; and (c) predicting the distribution of microplastics on the sea floor.

Interactions among late Cenozoic global cooling, tectonic activity and regional climate evolution of the northeastern Tibetan Plateau remain elusive. To further understand the relative contributions of global climate change and tectonism, we conducted a comprehensive study of heavy minerals, rock magnetism, and branched glycerol dialkyl glycerol tetraethers (brGDGTs) in late Cenozoic sediments of the Laojunmiao section (ca. 12.7 Ma to 5 Ma) in the Jiuxi Basin. Our results reveal a notable increase in magnetic susceptibility (χ) and saturation isothermal remanent magnetization (SIRM) at 8.5 Ma, aligning with an accelerated decrease in temperature captured by brGDGTs. Combined with heavy mineral analysis, we propose that the profound changes in magnetic parameters and temperature are closely linked to the intensive uplift of the northern Qilian Shan since 8.5 Ma. Furthermore, this ongoing uplift has occurred simultaneously with persistent aridification in the Jiuxi Basin and its adjacent regions. The Qilian Shan might have reached a threshold elevation and began to act as a moisture barrier to northwestward moisture since 8.5 Ma. By synthesizing hydroclimate evolution records from the northeastern Tibetan Plateau, we deduce that changing topography resulting from tectonic uplift may have exerted a significant influence on regulating the moisture distribution in this region during the mid- to late Miocene. • Temperature reconstructed using brGDGTs declined at an accelerated rate at 8.5 Ma • Magnetic enhancement of lacustrine-delta fan sediments occurred at 8.5 Ma. • The northern Qilian Shan was uplifted at 8.5 Ma, simultaneous with regional drying. • Tectonic uplift was the primary driver of this climate transition at 8.5 Ma. [ABSTRACT FROM AUTHOR]

Surficial sediment samples collected from the recently formed fluvial delta in Lake Nasser/Nubia (Egypt and Sudan) in conjunction with data on bottom current and depth soundings are examined to interpret hydraulic-sorting processes and transport/depositional patterns. The ~500 km long northeastward-trending lake, lies within Egypt and Sudan, is created as a result of the construction of the Aswan High Dam in 1964. The original grain-size distribution and heavy mineral compositions of these samples help to characterize the classical depositional features of the recently formed underwater delta-front and prodelta depocenters. Starting from the south, those delta-front deposits, which floor most of the narrow-shallow basin of Lake Nubia, are characterized by thick coarse-grained sandy deposits, rich in heavy minerals (averaged 12.8%). This delta-front is followed to the northeast by thin layers of prodelta mud, poor in heavy mineral contents (averaged 0.6%). These layers cover the entire broad basin of Lake Nasser. The northeasterly downslope fining-trend, along with a continuous decrease in heavy mineral composition, along the length of the lake, are attributable to processes of grain sorting, which take place due to contrasting densities and grain sizes. These processes lead to the concentration of heavy mineral placer, mostly in the delta-front samples. The sorting mechanism, in turn, is controlled by the interplay of unidirectional-directed northeastward current, physiographic characteristics of the lake, including topographic configuration, geometry (cross-section), and floor topography (slope gradient). In terms of mineral exploration, the highest proportion of mineral grades in the delta-front sediments is likely to be considered as a viable source for economic placers that require more planning initiatives for industrial and commercial evaluation. • This study is the first systematic demonstration of heavy minerals in the fluvial-delta of Lake Nubia. • Textural and mineralogical contents are used for identifying the delta-front and prodelta depocenters in this fluvial delta. • A very high concentration of heavy minerals occurs in the delta-front compared to that in the prodelta samples. • The sorting process in the lake is controlled by the effect of the bottom current, the lake's geometry and the bed slope. • The highest proportion of mineral grades in the delta-front can be used for industrial and commercial purposes. [ABSTRACT FROM AUTHOR]

The heavy minerals present in lithologic sand and sandstone units of Nanka Formation are mainly zircon, rutile, tourmaline, apatite, staurolite, and opaque minerals (Goethite, hematite, ilmenite), which are present dominant in weathered sandstones when analysed using petrographic varietal studies to infer provenance, diagenesis and source area weathering history. The low-diversity and relative abundance of heavy mineral assemblages are controlled by provenance and diagenetic processes, and these present limitations in accurate reconstruction of the paleo-history of these lithologic units using heavy minerals analysis alone. These lithologic Eocene units are derived from intensely weathered granitic and metamorphic source rocks and they are composed dominantly of matured polycyclic sediments.

The average thickness of Paleogene sandstones reaches about 3000 m or even 4000 m at the northern margin of the Qaidam Basin. However, the provenance of these sandstones has been uncertain; thus, more comprehensive research is needed. Integrated research was conducted on the provenance based on petrological characteristics, heavy mineral analysis, and U–Pb dating in the center of the northern Qaidam Basin. The results of lithofacies analysis show that the Paleogene sandstones were mainly derived from an active continental magmatic arc, subduction-accretionary or fold-thrust belt; The results of heavy mineral analysis show that the heavy mineral combinations in the Lenghu seventh area and Mabei area are consistent, mainly composed of zircon, garnet, magnetite, and leucosphenite. Moreover, GZi [garnet/garnet + zircon] and RZi [leucosphenite/(leucosphenite + zircon)] have good correlation with ZTR (the ZRT index refers to the proportions of three kinds of transparent heavy minerals in clastic rocks: zircon, rutile, and tourmaline). The zircon U–Pb results for the Paleogene sandstone in the northern Mabei area are consistent with the results of U–Pb dating in the middle of the South Qilian Mountains, which yielded the same results as river sand in the modern Yuka River. Based on three types of data, it is confirmed that the two areas, Lenghu seventh and Mabei, had the same sediment sources in the Paleogene, mainly from the middle of the South Qilian Mountains. The source rocks are mainly neutral - basic magmatic rocks and metamorphic rocks and the structure background is dominated by the magmatic island arc and the collision-thrust suture zone at the active continental margin.

Chronic kidney disease (CKD) in the North Central Province (NCP), Sri Lanka, is becoming a major cause of national burden with high mortality and morbidity. The origins of these kidney diseases are unknown, and the exact aetiology is not yet understood. Therefore, as an attempt to understand the effect of soil characteristics towards the disease, soil of surface (n = 25) and subsurface (50 cm depth, n = 25 of each) was collected from Horowpothana (HWP n = 50), Kabithigollawa (KBG n = 50), Medawachchiya (MWC n = 50) and Padaviya (PDW n = 50) of the NCP, where the highest number of patients is recorded. The soil samples were analysed using X-ray fluorescence for 22 major and trace elements, and the pH, electrical conductivity and oxygen reduction potential (ORP) for each sample were measured. The soil of all four villages mainly shows basic conditions. The high concentration of heavy mineral signatures in Horowpothana, Kabithigollawa, Padaviya and Medawachchiya could relate to high CKD patients in these four areas. The 50-cm soils of all four areas are in oxidized condition, while surface soil is in the anoxic condition. High fluctuation between surface and 50 cm may indicate high mobility of ions. According to the current study, P, F− and Fe2O3 ion could easily be mobilized into the groundwater of the area and thereby be related to the highest recorded CKD patients in these areas. Thus, as for the current study the heavy metals and elements that indicate the variations which causes health issues are Fe2O3, Pb, Zn, Cr, F−, Ti, Cu, Ni, V and Zr. [ABSTRACT FROM AUTHOR]

Deep‐water depositional systems are the ultimate sink for vast quantities of terrigenous sediment, organic carbon and anthropogenic pollutants, forming valuable archives of environmental change. Our understanding of the distribution of these particles and the preservation of environmental signals, in deep‐water systems is limited due to the inaccessibility of modern systems, and the incomplete nature of ancient systems. Here, the deposit of a physically modelled turbidity current was sampled (n = 49) to determine how grain size and grain type vary spatially. The turbidity current had a sediment concentration of 17%. The sediment consisted of, by weight, 65% quartz sand (2.65 g/cm3), 17.5% silt (2.65 g/cm3), 7.5% clay (2.60 g/cm3) and 5% each of sand‐grade garnet (3.90 g/cm3) and microplastic fragments (1.50 g/cm3). The grain size and composition of each sample was determined using laser diffraction and density separation, respectively. The results show that: (a) bulk grain size coarsened axially downstream on the basin floor challenging the notion that basin floor deposits fine radially from an apex upon becoming unconfined; (b) no sample composition matched the input composition of the flow, indicating that allogenic signals can be autogenically shredded and spatially variable in sediment gravity flow deposits; and (c) microplastic fragments were concentrated in levee and lateral basin floor fringe positions; however, microplastic concentrations in these positions were lower than input, suggesting microplastics bypassed the sampled positions. These findings have implications for: (a) the development of 'finger‐like' geometries and facies distributions observed in modern and ancient systems; (b) interpreting environmental signals in the stratigraphic record; and (c) predicting the distribution of microplastics on the sea floor. [ABSTRACT FROM AUTHOR]

Identifying the provenance of aeolian deposits in semi-arid zones of China is beneficial in understanding Earth’s surface processes and helping to alleviate ecological stress. In this paper, we use grain-size, geochemical elements, heavy-minerals, and quartz grain morphology data to investigate the potential source of aeolian sands from the Ordos Deserts (Mu Us Sandy Land and Hobq Desert). Sedimentological, geochemical and geomorphological results indicate that significant provenance differences exist among various parts of the Mu Us Sandy Land, i.e., aeolian sediments from the southwest region are obviously distinct from other areas in the Mu Us Sandy Land but show the same external provenance with the Hobq Desert referring to the sorting, mineralogical maturity, geochemical characteristics, heavy-minerals, and quartz grain morphology. Comparing the samples from the Ordos Deserts with felsic rocks from potential sources via a serious of geochemical methods, we conclude that: 1) Aeolian sands from other regions of the Mu Us are a mixture of binary provenance, i.e., one originated from local lacustrine sediments and underlying sandstones, and another from the Alxa Plateau (AP) carried by northwesterly Asian winter monsoon. 2) The fluvial deposits denuded from the Qilian Orogenic Belt in the Northeastern Tibetan Plateau (NTP) and carried by the Yellow River are likely the initial material source for the southwest region of the Mu Us Sandy Land and the Hobq Desert. 3) The Yellow River plays a significant and critical role in sediment transport for sand seas in arid and semi-arid areas of northern China.

The Danish-Polish Trough – a large Trans-European sedimentary basin stretching from Denmark, through Germany, to south-eastern Poland and even further to the south into Ukraine, had undergone an uplift during the Late Cretaceous, which in consequence resulted in its inversion and development into the Mid-Polish Anticlinorium. In many existing paleotectonic interpretations, SE Poland, i.e. the subsurface San Anticlinorium and the recent-day Roztocze Hills area was included during the Late Cretaceous into the Danish-Polish Trough, representing its axial and most subsiding part. Such a paleotectonic model was the basis for facies and bathymetric interpretations, assuming that upper Cretaceous sediments deposited close to the axial part of the Danish-Polish Trough (e.g. Roztocze) were represented by the deepest facies. Several studies performed in recent years contradict this concept. The growing amount of data indicates that already from the Coniacian-Santonian times, this area was a land-mass rather than the deepest part of the basin - the same is true for the Campanian and Maastrichtian times. Additionally, recent discoveries of cyclic middle Campanian deposits of shallow deltaic origin, along with a decreasing contribution of terrigenous material towards the NE, have led to the adoption of new facies and bathymetric models, being all in opposite to most of the previous interpretations. The new interpretation implies the presence of a land-mass area in the place where formerly the deepest and most subsiding part of the Danish-Polish Trough was located. Here we document in detail the Late Cretaceous deltaic system, i.e. the Szozdy delta developed in the axial part of the Danish-Polish Trough. The middle Campanian deposits which crop out extensively in the middle Roztocze Hills region, close to the village of the Szozdy, exhibits coarsening-upward tripartite cyclothems. The sequence was deposited in a shallow-water, delta front platform setting. Three facies associations have been distinguished: (1) dark grey calcareous mudstone, deposited in prodelta environment, (2) yellow calcareous sandstone unit, interpreted as prograding delta front lobe deposits of fluvially-dominated though wave/tidally influenced setting, and (3) calcareous gaize unit deposited in areas cut-off from the material supply. The sequence as a whole was accumulated by repeated progradation and abandonment of deltaic complexes. This interpretation is supported by the new sedimentological, palynofacies, and heavy mineral data. The latter is also discussed in the context of their possible source rock provenance, which might suggest a different burial history than thought so far. The development of the Szozdy delta system is placed next to dynamic tectonic processes operating at that time in SE Poland, i.e. the inversion on the one hand, and the generation of new accommodation space for the deltaic deposits by enhanced subsidence. This discovery shed new light on our understanding of facies distribution, bathymetry, paleogeography, and paleotectonic evolution of the south-easternmost part of the inverting Danish-Polish Trough into the Mid-Polish Anticlinorium during the Late Cretaceous times. [ABSTRACT FROM AUTHOR]

The present research focuses on sediments' compositional analysis, in the Paraná Basin, to demonstrate provenance contributions for the volcano-sedimentary features distributed along three regions of the Basin's border. In this context, the analyzed sediments, which are generally attributed to the Botucatu Formation, interact with volcanic lava flows from the Serra Geral Formation, establishing a volcano-sedimentary interaction. Nonetheless, the classic description for the Botucatu Formation comprehends almost ubiquitous fine to medium sandstones, while the herein sedimentary rocks vary from fine-grained to very coarse sediments. The granulometry difference raises questions about unexplained events during the Cretaceous volcanism (Serra Geral Formation) over the Botucatu desert. Accordingly, the studied area is distributed into regions A, B, and C from the center to the eastern of the state respectively, covering the Paraná basin's border where the volcano-sedimentary rocks can be outcropped. The methodologies employed involve the analysis of tourmaline compositions and REE patterns. These analytical tools help identify provenance variations and the development of local processes. As a result, the data indicate the predominance of meta-pelites and metapsammites in region A, while in region C there is a prevalence of granitoids contribution, while region B is a transition area showing contributions of both meta-pelites, metapsammites, and granitoids that are attributed to some units of the Sul-Rio-Grandense Shield. • Combination of REE and tourmaline compositional analysis for provenance information. • Tourmaline compositions indicate petrogenetic contributions. • REE patterns validate local processes. • New facies parameters and local processes controlling granulometry. [ABSTRACT FROM AUTHOR]

As one of the major subduction-accretionary systems in the southeastern Central Asian Orogenic Belt, the Bainaimiao arc presents a valuable opportunity for investigating the subduction–accretion process of accretionary orogens. It is located adjacent to the northern margin of the North China Craton and developed arc-related deposits during the Silurian–Devonian period. In this paper, we employed heavy mineral geochemistry and U–Pb ages of zircon and rutile, to determine the provenance of the Silurian–Devonian deposits and reconstruct the paleogeography of the source area. The stratigraphic units involved include the Xuniwusu Formation of Early Silurian and the Xibiehe Formation of Early Devonian. Both the Xuniwusu and Xibiehe formations exhibit heavy mineral assemblages dominated by zircons and tourmalines. Nevertheless, the Xibiehe Formation contains Cr-spinels and garnets which are absent in the Xuniwusu Formation. Geochemical analyses of the detrital Cr-spinels exhibit characteristics of a supra-subduction zone ophiolite. The garnets originated from middle- to high-grade metamorphic rocks, as well as mafic and felsic rocks. The tourmalines in both formations primarily indicate a metasedimentary rock source, with a small percentage of Li-poor granitoid species in the Xuniwusu Formation. The U–Pb age spectra of both detrital zircon and rutile in the Xuniwusu Formation show multiple peaks. The age spectra consist of Precambrian ages, indicative of a recycled origin, as well as Paleozoic ages, suggesting a magmatic origin. In contrast, the U–Pb age spectra of zircon and rutile in the Xibiehe Formation display a unimodal age peak at ca. 455 and 490 Ma, respectively. These differences suggest a provenance shift from the Xuniwusu to Xibiehe formations. The Xuniwusu Formation was sourced from the Bainaimiao arc itself, whereas the Xibiehe Formation has a mixed origin of the Bainaimiao arc and Ondor Sum accretionary complex. The provenance change correlates with the unconformity between the two formations, suggesting a forearc uplift event. In combination with the previous research on the Tulinkai ophiolite, it can be inferred that the forearc uplift was triggered by ridge subduction of the Paleo-Asian Ocean plate at ca. 450–430 Ma. This research provided a new perspective on the ridge subduction of the oceanic slab in fossil orogens. • The Xuniwusu Formation was derived from the Bainaimiao arc. • The Xibiehe Formation was sourced from the Bainaimiao arc and Ondor Sum complex. • A provenance shift between the two formations was identified. • The presence of Cr-spinels and garnets indicates a forearc uplift event. • The forearc uplift is related to ridge subduction of the Paleo-Asian Ocean plate. [ABSTRACT FROM AUTHOR]

In this paper, we analyzed the grain size and heavy mineral compositions of 52 surface sediment samples collected from the Kompong Som Bay of Cambodia and the adjacent rivers to depict the marine sedimentary environments and transport processes. Heavy minerals in sediments are dominated by authigenic pyrite, siderite, and tourmaline, with average percentages of 36.52%, 29.02%, and 10.94%, respectively. Two provinces can be divided according to the spatial similarity of minerals. The sediments from Province I, covered by silt grains in the northern bay, are characterized by autogenic pyrite, indicating a weakly reducing environment; whereas in Province II, covered by sand grains in the southern bay, the siderite-tourmaline-authigenic pyrite-zircon-hornblende assemblage occurs, indicating a mild reducing environment and locally oxidizing environment. Most of the sediments in the Kompong Som Bay are introduced from the Preak Piphot River and Srae Ambel River, except that some of them in the south areas come from coastal erosion. Generally, the sediments are difficult to be transported because of the low sediment loads entering the sea and weak hydrodynamic conditions. However, they are transported from the north to the south during the tide ebbing when the hydrodynamic force is much stronger. The sediment distribution and transport patterns are controlled by many factors, including submarine topography, hydrodynamic conditions, the southwest monsoon, land contours, and sediment supply. [ABSTRACT FROM AUTHOR]

In the Transdanubian Range, Pannonian Basin, Hungary, karstic sinkholes on a planation surface of Triassic carbonates are filled by grey clayey–silty kaolin deposits. The provenance and accumulation age of these strongly altered terrestrial karst-filling sediments are constrained by X-ray powder diffraction, heavy mineral analysis and zircon U–Pb dating. The heavy minerals of the Southern Bakony Mountains samples are dominated by the ultra-stable zircon–rutile–tourmaline association. Zircon U–Pb data indicate accumulation between 20 and 16 Ma. Furthermore, Archaean to Palaeogene grains were also determined, reflecting the principally fluvial recycling of Eocene bauxites and their cover sequences. In contrast, the sample from the Keszthely Hills consists almost exclusively of airborne material including zircons of 18–14 Ma, reflecting a dominant contribution from the Carpathian–Pannonian Neogene volcanism. The shift in the Miocene age components is inferred to have been caused by the landscape evolution and burial history of the planation surface remnants controlled by local block tectonics. [ABSTRACT FROM AUTHOR]

Magnetite is typomorphic, and its crystal textures and chemical fingerprint form unique signatures that can be used to determine sediment provenance. Determination of the provenance of sediments in the upper Yangtze River is critical for understanding its evolution and the uplift of the Tibetan Plateau. In this study, petrographic analysis and electron-probe microanalysis (EPMA) of 800 detrital magnetite grains were performed to differentiate the provenance of sediments within the mainstream and major tributaries of the upper Yangtze River catchment. Chemical analyses show that the elemental composition of magnetite grains shows pronounced variations among the different sections of the mainstream and tributaries. Based on the observed chemical fingerprints, we infer that the source rocks control the elemental composition of magnetite grains. The magnetite contribution is closely related to the tectonics, climate, and erosion of parent rocks within different drainage basins. Magnetite from the trunk stream of the Jinsha River is found to be a significant contributor to the upper Yangtze River. Magnetite grains of the upper Jinsha River are primarily derived from source areas composed of silicic plutonic rocks and ophiolite lithologies that crop out on the SE Tibetan Plateau. Magnetite grains within the sands of the lower Jinshajiang sediments are characterized by high concentrations of Ti, Mg, Cr, Al, and Mn, and are derived from the widely distributed Emeishan flood basalts and Pan-Xi layered basic–ultrabasic igneous rocks. This source is also a major contributor of magnetite to the upper Yangtze River, and the parent rock distributed in this region is of typomorphic significance to the development of the Yangtze River. The origin of magnetite grains in the tributaries depends on the parent rocks distributed in their catchments. In summary, the presence of detrital magnetite grains provides valuable information for discriminating the provenance of sediments in the upper Yangtze River drainage basins. [ABSTRACT FROM AUTHOR]

The development and formation times of the Yellow River, the second largest drainage system in China, remain controversial. The Ganhegou Formation, a set of Upper Miocene–Pliocene fluvial facies sediments, developed around Niushou Mountain in the outermost edge of the arcuate structural belt in the northeastern margin of the Tibetan Plateau and has a sediment composition very similar to that of the Yellow River. In this article, the relationship between the deposition of the Ganhegou Formation and the Yellow River is confirmed through the analysis and comparison of sediment composition, detrital zircons, and heavy mineral characteristics of the Ganhegou Formation, a Yellow River terrace, and the modern Yellow River. The sediments of the Ganhegou Formation contain abundant well‐ground and sorted fluvial pebbles that are largely consistent with Yellow River sediments. The analysis of the composition of zircons and heavy minerals shows that the age peaks of all detrital zircons are primarily among 200–300 Ma, 400–500 Ma, and 1,700–2,000 Ma and that all the heavy minerals are generally characterized by the combination of 'haematite + garnet + zircon + epidote + quartz and altered minerals'. Therefore, the Ganhegou Formation in the Niushou Mountain area of Ningxia is a likely sediment of the ancient Yellow River, which has existed at Qingtongxia since at least the Late Miocene. [ABSTRACT FROM AUTHOR]

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Central Asia loess deposits can yield detailed records of aridification across the Asian interior, as well as the atmospheric circulation. In this study, we presented grain size, heavy mineral assemblage, rock magnetism and anisotropy of magnetic susceptibility of a loess section in the Tacheng Basin in Xinjiang region, NW China. The results of anisotropy of magnetic susceptibility indicated that a near-surface SE wind prevailed in the Tacheng area since Marine Isotope Stage (MIS) 3, while a near-surface SW prevailing wind developed during MIS3b. We inferred that the change of wind direction was due to glacial advance during MIS3b. Combining the result of anisotropy of magnetic susceptibility with grain size, heavy mineral assemblage data and previously published low-field mass susceptibility revealed that dust transported by the near-surface SW wind had a greater ability to enhance magnetic susceptibility and higher amphibole/epidote ratio. Additionally, a strong Siberian High during Heinrich Event (H)5 at ca. 48 ka blocked the advection of moisture into the region via mid-latitude westerlies, causing glacial recession and the weakening of the prevailing SW wind. Our study has implications for identifying changes in paleo-wind direction and dust source, which can aid understanding of the influence of westerlies and the Siberian High on dust accumulation, as well as their interactions. [ABSTRACT FROM AUTHOR]

The Upper Cretaceous Deposits of the Anambra Basin has a part of its sedimentary rock deposited in the Auchi area of Edo State. Geologic field and Sedimentological studies carried out on twenty eight (28) selected samples from a section of a road--cut show that the sediments range from fine through medium to coarse grained. Morphoscopic studies reveal subangular to subrounded outline of sand particles. These coupled with the various colours observed in the sediment, ranging from whitish sand through yellowish brown, pink and reddish brown possibly indicate a non--marine environment and a fluviatile to deltaic environment of sedimentation is suggested. Heavy mineral assemblage made up mainly of opaque, andalusite, zircon, hornblend, sphene and epidote suggest derivation from the Precambrian Igneous and medium to high grade metamorphic rocks of the underlying Basement Complex of Nigeria. [ABSTRACT FROM AUTHOR]

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Based on the analysis results of thin sections, cathodoluminescence of quartz and heavy mineral assemblages, combined with sedimentary structures and seismic reflection characteristics, the provenance direction, parent rocks and evolution characteristics of Upper Triassic-Middle Jurassic in the eastern Kuqa depression of Tarim Basin were studied. The results show that the provenance of Upper Triassic-Middle Jurassic in the eastern Kuqa depression of Tarim Basin is mainly from South Tianshan orogenic belt in the north, and the parent rocks are mainly magmatic and metamorphic with a few sedimentary. Among them, there is a higher content of terrigenous clastic lithic and quartz without luminescence in the sandstone of Taliqike Formation, and the heavy mineral assemblages are characterized by higher contents of zircon, leucosphenite and magnetite, and lower contents of garnet, indicating that the parent rocks may be early deposition of Upper Ordovician-Upper Triassic; the contents of magmatic rock lithic in the sandstone of Ahe Formation and Yangxia Formation increase, the heavy minerals are characterized by higher contents of garnet, and quartz mainly gives off blue-purple and tan light under the condition of cathodoluminescence, indicating that the parent rocks of Ahe Formation and Yangxia Formation mainly come from Permian and its underlied sediments; the contents of metamorphic rock lithic and quartz with tan luminescent in the sandstone of Kezilenu'er Formation and Qiakemake Formation increase obviously, and the content of garnet is extremely high, indicating that the influence of metamorphic parent rock is enhanced. The evolution of parent rocks in the provenance area of Late Triassic-Middle Jurassic has obvious regularity. The parent rocks are mainly sedimentary in Late Triassic, and the contents of magmatic parent rocks increase in Early Jurassic, and finally, it is characterized by metamorphic parent rocks in Middle Jurassic. In Late Triassic, the South Tianshan orogenic belt is greatly uplifted in the eastern Kuqa depression, as a result, a large number of metamorphic parent rocks are involved in the orogenic belt and denuded; in Early-Middle Jurassic, the tectonic activity in the middle section of South Tianshan orogenic belt is characterized by east and west sections, the sandstone in the eastern region firstly has high content of garnet in Early Jurassic, while the sandstone in the western region does not appear garnet abundance until Middle Jurassic. It shows that Hula and E'erbin mountains in the middle section of South Tianshan orogenic belt are uplifted and denuded strongly in Early Jurassic, but Halke mountain is uplifted consumingly in Middle Jurassic. [ABSTRACT FROM AUTHOR]

Microtextures of quartz and zircon grains from the Bosque and Paseo del Mar beaches in the Gulf of Mexico were examined using a Scanning Electron Microscopy (SEM), to infer their provenance and palaeoenvironment. A total of 16 microtextures from 200 grains were identified and were grouped into mechanical, chemical, and mechanical/chemical origin. Microtextures of mechanical origin represent parallel striations (ps), cracks due to collision (ck), conchoidal fractures (cf), v-shaped marks (vs), abrasion fatigue (af), meandering ridges (mr), chattermarks (ch), curved (cg) and straight grooves (sg), which are attributed to a high-energy fluvial and sub-aqueous marine environment. Solution pits (sp), crystal overgrowth (cro), and silica globules (sgl) of chemical origin indicated precipitation and dissolution in a silica saturated marine environment. Adhered particles (ap), elongated depressions (dp), and relief are grouped as mechanical/chemical origin, suggested a sub-aqueous nearshore marine environment. Although zircon is considered as a resistant mineral, the frequency of microtextures observed was higher in zircon than in quartz. The results of this study revealed that the Los Tuxtlas volcanic field, Chiapas Massif and Oaxacan Complexes in the SW Gulf of Mexico are the potential source areas, which supplied sediments to the Paseo del Mar and Bosque beach areas. Highlights: Microtextures of quartz and zircon grains in the Bosque and Paseo del Mar beaches in the SW Gulf of Mexico were analyzed. Frequency of microtextures are higher in zircon than in quartz grains revealed that microtextures are independent of grain hardness. The dominance of microtextures of chemical origin in the Paseo del Mar beach suggested a low-energy environment with carbonate rich sediments. Chiapas Massif and Oaxacan Complexes are identified as the potential source areas, which supplied sediments to the beach areas. [ABSTRACT FROM AUTHOR]

In this study, we report the high-resolution heavy mineral records from a 200.30 m long borehole (YRD-1101) on the northern coast of modern Yellow River delta (YRD), covering the last ~1.90Myr. The results show that the heavy mineral assemblages are dominated by epidote, followed by hornblende, garnet and hematite-limonite. In the Yellow River (YR) sediments, the content of hornblende is higher than the epidote, and the epidote to hornblende ratios (E/H) are lower than the core YRD-1101. The E/H show two distinct lower values at depositional unit (DU) 4–2 (117.9–125.6 m) and DU 4–1 to DU 2 (13.5–99.3 m), indicating the obvious influence of YR sediments. The heavy mineral composition of DU 5 is distinct from YR sediments and interpreted as the result from heterogeneous provenance of the adjacent ancient rivers, while DU 4 to DU 1 resemble the upper-middle reaches of the YR sediments. The different sediment types (mud, sandy silt and silt) of core YRD-1101 do not contain markedly different transparent-heavy-mineral assemblages in terms of concentration and mineral ratios. No matter how sedimentary environment changes, the ratios of epidote and hornblende show very stable values in DU 4–1 and DU 3 due to the influence of YR sediments. The transparent-heavy-minerals such as hornblende, epidote and other stable minerals, which were relatively stable, are controlled primarily by provenance, while the sedimentary environment mostly influences the flaky minerals and the authigenic minerals. This study provides evidence regarding the history of the lower reaches of the YR and YRD since the early Pleistocene, highlighting river's important role for the evolution of the western coast of the Bohai Sea (BS). • The core YRD-1101 sediments are mainly derived by the Yellow River. • Epidote/Hornblende (E/H) ratio is relatively stable under hydraulic sorting and can be used as an indicator of the source areas. • The proportions of transparent-heavy-minerals of the core YRD-1101 are controlled primarily by provenance. [ABSTRACT FROM AUTHOR]

应用X射线衍射对青藏髙原东北缘尖扎盆地加让剖面11.8～5.8 Ma的地层沉积物进行矿物分析,结果表明加让剖面沉积物矿物组分主要包括碎屑矿物、碳酸盐矿物和黏土矿物。其中,以碎屑矿物居多,主要是石英、斜长石、云母类矿物(白云母、黑云母),及少量尖晶石、辉石类矿物(普通辉石、锰钙辉石及顽火辉石等)、金红石、刚玉、磁铁矿、钛磁铁矿、榍石、霞石,偶见锆石、石榴子石、锐钛矿; 碳酸盐矿物以方解石居为主,白云石占比较少; 黏土矿物中,绿泥石占比最高,还有少量赤铁矿、蛭石和沸石。以全岩矿物指标研究为主,结合加让剖面沉积相演化特点,并以磁化率变化为参考,进行系统的矿物学研究,获得了尖扎盆地在11.8～5.8 Ma蕴含的古气候环境演化大致可分为4个阶段:11.8～10.0 Ma,气候干冷期; 10.0～8.6 Ma,气候暖湿波动期; 8.6～6.2 Ma,气候温暖湿润期; 6.2～5.8 Ma,气候干冷期。在约10.0、8.6、7.2 Ma附近,主要矿物占比及组合特征有明显改变,当时的古环境状况发生急剧变化,可能揭示青藏高原东北缘在10～8 Ma期间广泛发生了一系列较强烈的构造运动,来源于周边山脉的剥蚀使得研究区沉积的近源物质增多,约7.2 Ma之后的古环境演化过程主要受青藏高原构造隆升以及全球气候变冷协同影响。 [ABSTRACT FROM AUTHOR]

The Three Gorges valley is one of the two key capture points of the evolution of the Yangtze River, yet the formation of this valley—from the pre-Miocene to the late Pleistocene—remains uncertain. The Jianghan Basin, a late Mesozoic–Cenozoic basin located just downstream of the Three Gorges valley, is a crucial area for understanding the formation of the valley. In this study, we used heavy mineral assemblages to trace the provenance of Pliocene–Pleistocene sediments obtained from the 300-m-depth Zhoulao drillcore in the Jianghan Basin. Results show that heavy mineral concentrations, compositions, and species display a clear change at a depth of 110 m in the studied core, consistent with the change in values of magnetic indexes and trace-element geochemical indicators. The heavy mineral assemblage deposited below a depth of 110 m (lower section of the core) comprises zircon, epidote, leucoxene, rutile, anatase, pyrite, and titanite, whereas that deposited above 110 m (upper section) consists of hornblende, pyroxene, garnet, hematite-limonite, and magnetite. In addition, the heavy mineral assemblage of the upper section is similar to that of the modern surface fluvial sediments of the Yangtze, which indicates that materials of the upper core section of the Jianghan Basin were sourced from the upper Yangtze River Basin, west of the Three Gorges. After incision of the Three Gorges valley, sediments from the upper Yangtze were transported to the Jianghan Basin and deposited. Combining the results of this study with the known paleomagnetic chronology of the Jianghan Basin, we propose that the Three Gorges valley was incised at ca. 1.1 Ma.

Analyses result of the heavy minerals that was took from beach sediments and sea floor surficial sediments was founded ten heavy minerals namely hematite, magnetite, limonite and rutile from oxide and hydroxide group, pyroxene, amphibol and zircon from silicate group, biotit from mica group, barite from sulfide group and dolomite from carbonate group. From 10 minerals identified, only magnetit distributes in the whole area, with the highest percentage of 34,15% in the sea and 35,14 % on beaches. Other heavy minerals distribute locally with the percentage of less than 0,01 %. Grain size analyses result of sea floor surficial sediment had identified six units sediment such as sand, sand with few gravel, sandy gravel, gravely sand, gravel and reef. Distribution area of the six units sediment as follows sand and sandy gravel are occupied 25 % respectively of the study area, reef 20%, sand 15 %, gravel 10 % and gravely sand occupied 5%. The best sediment for making art goods is sand sizes which is rich of heavy minerals such as magnetite, hematitre, limonite, zircon, pyroxene and amphibol. If will be exploited of the sand sediment on beach or sea floor surficial sediment, should be considering of the environment sustainable.

Nima basin which is located in the Bangongco suture was surrounded by several thrust faults and its paleogeographical features and tectonic evolution process can be restored by the Paleogene sediments. Based on the methods of petrology, sedimentology, and zircon chronology, the features of provenance, paleogeography and tectonic activities of the Nima basin were analyzed through studying its Paleogene section. The compositional characteristics of sandstones, paleocurrent direction, and zircon U-Pb chronology indicate that the adjacent terranes and the thrust belts in the suture zone are the provenance areas for Nima basin. Qm-F-Lt, Qt-FL triangular diagram shows that the component of sandstones mainly belongs to the recycling orogenic zone, and indicates that the southern depression experienced intensive tectonic activities during the Paleogene period. Based on the characteristics of heavy minerals and sediments, the tectonic evolution of the south depression of Nima basin can be divided into four stages: the stable stage in Early Eocene, the strong active stage in Late Eocene, the highly stable stage in Early Oligocene, and the highly active stage in Late Oligocene. The collision between the Indian plate and Eurasian plate in the Early Cenozoic period led to the crustal shortening and uplifting of the Nima basin and the reactivating of the thrust fault system. The ancient river system which developed due to the uplift of the surrounding terrain and the strong tectonic orogeny provided debris deposits to the sedimentary center of the ancient lake, and therefore the coarse debris of fan delta develops on the edge of the steeper terrains of the lakes. The southern Nima basin eventually evolved into an independent sedimentary depression with multi-directional source and its paleogeography feature depended on the regional tectonic activity. [ABSTRACT FROM AUTHOR]

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