Heavy Mineral Analysis Research Articles

Propagation, Growth and Haematology of Fish Cultured in Water from a Natural Stream and Underground Tubewell Sources

Propagation, growth and haematology of Clarias gariepinus bred and reared in water from a natural stream at 5o28’N, 7o32’E (Nature stream) and two wells at 5.4810N, 7.5370E (well-1) and 5.4770N, 7.5390E (well-2) were studied. The study was carried out in search of suitable water within close proximity for fish propagation. Growth was evaluated once in two weeks. Haematological parameters of the fingerlings were examined at 70 day post hatch. There was significant difference (P<0.05) in egg fertilization, hatchability, larval survival, growth and blood parameters among the treatments. Fish exposed to water from the natural stream impacted best propagation indices including fastest growth and highest values of Packed Cell Volume (PCV) and Mean Corpuscular Haemoglobin Concentration (MCHC). Fish for well-1 and well-2 were not statistically different (P>0.05) in PCV and MCHC. Apart from these two parameters, values of all the other blood parameters including growth were significantly lower (P<0.05) in fish for well-2 than those for well-1. The disparities observed signifies differences in water quality which is indicative for the presence of contaminant not identified in this study. The report recommended inclusion of heavy metals and organic mineral analysis in future study to identify the cause of the observed alterations.

Interplay of Multiple Sediment Routing Systems Revealed by Combined Sandstone Petrography and Heavy Mineral Analysis (HMA) in the South Pyrenean Foreland Basin

Combined sandstone petrography and heavy mineral analysis allow to decipher different sediment routing systems that could not be resolved by one method alone in the South Pyrenean foreland basin. We apply this approach to deltaic and alluvial deposits of the southern part of the Jaca basin, and in the time equivalent systems of the nearby Ainsa and Ebro basins, in order to unravel the evolution of source areas and the fluvial drainage from the Eocene to the Miocene. Our study allows the identification of four petrofacies and five heavy-mineral suites, which evidence the interplay of distinct routing systems, controlled by the emergence of tectonic structures. Two distinct axially-fed systems from the east coexisted in the fluvial Campodarbe Formation of the southern Jaca basin that were progressively replaced from east to west by transverse-fed systems sourced from northern source areas. In the late stages of evolution, the Ebro autochthonous basin and the Jaca piggy-back basin received detritus from source areas directly north of the basin from the Axial Zone and from the Basque Pyrenees. Coupling sandstone petrography with heavy mineral provenance analysis allows challenging the existing model of the South Pyrenean sediment dispersal, highlighting the relevance of this approach in source-to-sink studies.

Provenance of the Early–Middle Devonian Shugouzi Formation in the Quruqtagh, Northeastern Xinjiang: Constraints from Sandstone Geochemistry and Heavy Mineral Analysis

AbstractThe Early–Middle Devonian Shugouzi Formation in the Quruqtagh block consists mainly of clastic rocks. However, their provenance has been scarcely studied since it was named. Geochemistry of clastic rocks was commonly used to interpret the provenance. Detrital heavy mineral analyses help frame the U‐Pb age from zircon grains, integrated with geochemical data from detrital tourmaline and spinels. These techniques were used to characterize components of the sediment flux and define erosion areas in the Qurugtagh block, further providing evidence about the tectonic evolution of the South Tianshan and Tarim plate. The maximum depositional age constrained by detrital zircon dating was Early–Middle Devonian. Multiple diagrams for sedimentary provenance using major and trace elements indicate that continental island arc‐related felsic rocks were the major source rocks for the Shugouzi Formation. Detrital tourmalines are dravite and schorl. The results of detrital tourmaline electron probe microanalysis (EPMA) show that the source rocks are mainly metasedimentary rocks and granitoids. The detrital chromian spinels within the sediments are characterized by high chroumium (Cr#) and varying magnesium (Mg#). The discrimination plots reveal that these spinels were sourced from island arc magmatic rocks. The laser ablation inductively‐coupled plasma mass spectrometry (LA‐ICP‐MS) U‐Pb chronology of detrital zircons suggests that the sediments were derived mainly from 414–491 Ma and 744–996 Ma magmatic rocks. Paleocurrent restoration, sandstone geochemistry, EPMA, and detrital zircon geochronology indicate that the source rocks were predominantly derived from Late Ordovician and Devonian magmatic rocks and subordinately from recycled Neoproterozoic magmatic rocks. Comprehensive analyses of the source areas suggest that a remnant arc still existed in the Early Devonian and the Shugouzi Formation was deposited in a passive continental margin.

Mineralogical Variation of the Banks of Shatt Al-Arab and Shatt Al-Basrah River Sediments in Southern Iraq

The sediments on the banks of Shatt al-Arab and Shatt Al-Basrah have been studied to find out their mineralogical variation. Twenty-two samples were collected from depths of 20 cm of recent sediments Shatt Al-Arab and Shatt Al-Basrah Rivers banks, with approximately equal distances between them, the grain size analysis was conducted, and selected samples were prepared for X-ray diffraction, heavy and light minerals analysis. The result of grain size analysis showed that silt loam texture is dominated in Shatt Al-Arab River while silty clay loam texture in Shatt Al-Basrah River. quartz, calcite, dolomite, feldspar, and halite represent the light minerals in the silt fraction in the study area sediments, while the clay minerals are represented by kaolinite, palygorskite, illite, and montmorillonite-chlorite in Shatt Al-Arab River and the same clay minerals with small amount of montmorillonite in Shatt Al-Basrah River. The petrographic analysis showed that the light mineral contents in the sand fraction are composed primarily of quartz, feldspar, and rock fragment. The main rock fragments consist of carbonate, chert igneous and metamorphic rocks, mudstone, and evaporates (Gypsum). The heavy minerals contents are opaque minerals, pyroxene, hornblende, chlorite, biotite muscovite, epidote, staurolite, kyanite, garnet, tourmaline, rutile, and zircon.

The Paleogene Gosau Group Slope Basins of the Incipient Eastern Alpine Orogenic Wedge: A Case Study at the Gams Basin (Austria)

This study investigates the Paleogene deep-water depositional system of the Gosau Group at Gams, Styria (Austria). The examined sections of the Danian to the Ypresian age (NP1–NP12) comprise sediments of the Nierental and Zwieselalm Formations. Four deep-water clastic facies assemblages were encountered: (1) pelagic marls with thin turbidites, (2) carbonate-rich turbidites, (3) carbonate-poor turbidites, and (4) marl-bearing turbidites; slump beds and mass flow deposits are common features in all facies assemblages. Based on heavy mineral, thin section, microprobe, and paleoflow analyses, provenance was from the surrounding Northern Calcareous Alps (NCA) rocks and exhuming metamorphic Upper Austroalpine units to the south. In addition, biogenic calcareous material was delivered by adjacent contemporaneous shelf zones. The sedimentary depocenter was situated at the slope of the incipient Alpine orogenic wedge, in frontal parts of the NCA, facing the subducting Penninic Ocean/Alpine Tethys. The evolution of the Gams Basin was connected to the eoalpine and mesoalpine orogeny and the adjunctive transpressional setting. The Gams deep-water depositional system is interpreted as an aggrading or prograding submarine fan, deposited into a small confined slope basin, positioned along an active continental margin, bound and influenced by (strike-slip) faults, related to crustal shortening. The development of the Gams slope basin and its infilling sequences was mainly dominated by tectonism and sediment supply, rather than by eustatic sea-level fluctuations. The basin was cut off during the Eocene due to renewed orogeny. A Quaternary analogue for the Upper Cretaceous to Paleogene basin setting of the Gams area is represented by the Santa Monica Basin in the California Continental Borderland.

Sedimentary and Source-to-Sink Evolution of Intracontinental Basins: Implications for tectonic and Climate Evolution in the Late Mesozoic (Southern Junggar Basin, NW China)

Sedimentary investigations, petrography, heavy mineral and conglomerate component analyses, and detrital zircon U-Pb geochronology were conducted to reconstruct the sedimentary and source-to-sink evolution of the Southern Junggar Basin, an intracontinental basin in the late Mesozoic. A paludal deltaic environment evolved into a fluvial environment, and abruptly prograded into alluvial fan and aeolian environments in the Late Jurassic, which was replaced by fan deltaic and lacustrine environments in the Early Cretaceous. Three source-to-sink systems were identified, according to different source-to-sink system features. In the northern piedmont of the Tianshan Orogenic Belt, the North Tianshan Orogenic Belt mainly provided sediments in the Late Jurassic. The North Tianshan and Central Tianshan Orogenic Belt both supplied sediments in the Early Cretaceous. In the northern piedmont of the Bogda Orogenic Belt, the Bogda Orogenic Belt was constantly the primary provenance, and the Tianshan Orogenic Belt also provided sediments. Sediment recycling occurred in the basin margin in the Late Jurassic and more metamorphic rocks were denudated in the Early Cretaceous. The source-to-sink system shrank in the Late Jurassic and expanded in the Early Cretaceous. This source-to-sink evolution and the conglomerates in the Kalazha Formation with seismite structures responded to the aridification in the Late Jurassic, the uplift of the Bogda and Tianshan Orogenic Belts in the Late Jurassic, and the exhumation of the Bogda and Tianshan Orogenic Belts in the Early Cretaceous.

Climate-driven drainage reorganization of small mountainous rivers in Taiwan (East Asia) since the last glaciation: The Zhuoshui River example

As an important component in East Asia sediment source-to-sink systems, small mountainous rivers in Taiwan deliver disproportionately large amounts of sediments to oceans. Although the modern fluvial sediment transport processes, discharge fluxes and sediment compositions have been well investigated, the drainage evolution of these mountainous rivers remains understudied and sediment fluxes are expected to vary greatly in glacial-interglacial cycles due to the tremendous climatic fluctuations. To define how the drainage of Taiwan mountainous rivers has evolved since the last glaciation, we target a sediment core (98 m in length) from the Zhuoshui River delta, western Taiwan and conduct sediment petrography, heavy mineral analysis, detrital zircon U Pb geochronology and clay mineralogy to investigate provenance variations and river basin evolution since 60 ka. Sediments of the last glaciation show comparatively high illite crystallinity index values, low metasedimentary lithic fragment and stable heavy mineral contents and similar detrital zircon U Pb ages with downstream signatures, indicating prominent sediment contributions from the Coastal Plain and Western Foothills regions (elevation <1 km) during the glaciation. However, characteristics of the deglacial and Holocene sediments indicate high contributions from the higher Hsueshan Range and Central Range regions (elevation >1 km). We suggest that headward extension and drainage capture since the deglaciation, which was most likely due to the increasing monsoon rainfall, account for the provenance variations in the discharged sediments. This implies a climate-driven drainage reorganization of the small mountainous rivers in Taiwan since the last glaciation. Our findings highlight the previously-overlooked, variable provenance information from Taiwan in glacial-interglacial cycles, and the dynamic source signatures are important to East Asia sediment source-to-sink studies. • The provenance of Zhuoshui River sediments has changed since the last glaciation. • The provenance variation was caused by climate-driven drainage reorganization. • The river system of Zhuoshui River was not developed during the last glaciation. • The Zhuoshui River headward extended and captured other basins in the Holocene.

Provenance and tectonic setting of the Gudongjing Group in Beishan Orogen

增生造山带中陆源碎屑岩物源区特征的研究可为解剖造山带结构甚至大陆地壳的形成和演化提供关键证据。北山造山带中部的古硐井群被认为是前寒武纪稳定沉积盖层，是北山造山带存在微陆块的重要依据。本文围绕古硐井群的物源区特征，进行了碎屑颗粒和重矿物统计、全岩主微量元素地球化学分析、碎屑锆石U-Pb年代学和Hf同位素测试。古硐井群碎屑岩的碎屑颗粒多呈棱角状，主要为石英、长石，同时含大量硅质岩碎屑和一定数量的火山岩碎屑；重矿物组成以褐铁矿、锆石、白钛石、尖晶石为主，角闪石、电气石、辉石次之，暗示物源区可能存在蛇绿岩、增生杂岩。全岩主量元素以高硅、高铝、富碱、低锰为特征，结合REE、Cr、Co、Sc和Th等惰性元素含量特征共同指示了长英质的物源区。最年轻的碎屑锆石年龄为443.9±13Ma，表明古硐井群最大沉积时限为晚奥陶世。碎屑锆石的年龄高度集中于470Ma附近，且该区间锆石ε_Hf（t）值多为正值，指示物源区存在大量新生地壳物质。本文推测古硐井群可能形成于增生楔楔顶盆地；研究结果支持北山造山带是古生代持续增生造山的产物这一认识。;The clastic sedimentary rocks in an accretionary orogenic belt may preserve key evidence for understanding the architecture of orogenic belts and even the crustal evolution. The clastic sedimentary rocks of the Gudongjing Group in the middle of the Beishan Orogen is considered to be a set of stable sedimentary caprocks of the Precambrian, and it is also an important basis for the existence of micro-continents in the Beishan Orogen. In this paper, statistics on clastic particle grain sizes and heavy mineral compositions, the whole rock geochemical composition analyses, detrital zircon U-Pb dating, and Hf isotope testing are carried out on the clastic rocks of the Gudongjing Group to reveal their prevenances and tectonic settings. The clastic components of the rocks are mainly composed of quartz, feldspar and rock fragments which are mainly siliceous rock fragments together with a certain amount of volcanic ones. Heavy mineral analysis reveals they mainly consist of limonite, zircon, ilmenite and spinel, followed by hornblende, tourmaline and pyroxene, which indicates the contribution of the accretionary complex materials and ophiolites to their provenance. The whole rock major element compositions are characterized by high contents of silicon, aluminum and alkali, while low in manganese. The contents of the inert elements, such as REE, Cr, Co, Sc, Th, etc., show characteristics of a felsic source area. The youngest detrital zircon age obtained in this study is 443.9±13Ma, indicating that the maximum deposition age of the Gudongjing Group is Late Ordovician. The age of detrital zircons is highly concentrated around 470Ma, and the corresponding zircon ε_Hf(t) values are mostly positive, indicating a large number of new crustal materials have developed in their provenance area. Based on the comparative analysis, it is suggested that these clastic rocks are possiblely formed in a slope basin on the top of an accretionary wedge. The results support the point that the Beishan orogenic belt is the product of a continuous accretion of a Paleozoic orogenic belt.

Neon isotopic signature applied to detrital provenance assignment in foreland basins

Cosmogenic noble gas isotope 21Ne in terrestrial rocks has been used primarily to determine timing and rates of the Earth's surface evolution. Here we explore the ability of detrital 21Ne as a provenance tracer, considering that Ne isotopes produced in source rocks could be preserved in minerals over geological time and might be predominant in total Ne inventory of sediments sunk in basins. This ability is predicated on potential source terranes of a given stratigraphic section with distinct neon isotopic signatures. Here we analyze neon isotopes of a well-dated Miocene–Pleistocene sedimentary archives in Kuqa foreland basin of southern Tianshan. The data suggest that the neon isotopic signature, which is expressed as εNe and defined in this work as the excess 21Ne/20Ne-ratio relative to atmospheric ratio, is stratigraphically sensitive to changes in local source terranes. This result is compatible with U/Pb provenance analysis and also supported by evidences from sandstone petrography and heavy mineral analysis. Influence of other non-source related 21Ne components in sedimentary archives on sensitivity of εNe has proven to be negligible. Furthermore, the integrated stratigraphic signatures of neon isotope and U/Pb age permit the detection of differential erosion in drainage basin, by which the tectonic or climatic effects on geomorphic evolution could be deciphered.

Heavy mineral analysis of the Turonian to Maastrichtian exotics-bearing deposits in the Western Carpathians: What has changed after Albian and Cenomanian?

Heavy mineral analysis of the Turonian to Maastrichtian exotics-bearing deposits in the Western Carpathians: What has changed after Albian and Cenomanian?

Geochemical and heavy mineral signatures of marine incursions by a paleotsunami on the Miyazaki plain along the Nankai–Suruga trough, the Pacific coast of southwest Japan

Earthquakes and tsunami repeatedly occur in the coastal areas of the Japanese islands, which are located on the margin of continental plates. Paleotsunami deposits in these areas provide important clues regarding the reconstruction of past marine incursions by earthquakes and tsunami. The Miyazaki plain on the Pacific coast of southwest Japan along the Nankai–Suruga trough has been also affected by marine incursions by previous interplate earthquakes and tsunami. Tsunami deposits are usually identified by their geological, sedimentological, and geochemical characteristics. In the present work, portable energy dispersive X-ray fluorescence spectrometry (portable XRF), X-ray analytical microscopy (XGT), statistical analyses, and heavy mineral analyses were performed to characterize the paleotsunami deposits of the Kanbun Hyuganada earthquake (age, 1662 common era) in the SY03 core from the south Miyazaki plain. Our new findings can be summarized as follows: (1) Increases in the Ti-normalized values of S, Ca, Fe, and Sr, and depletions of K were observed in the deposits; (2) Accumulation of Zr and heavy minerals such as zircon, likely related with the high-energy tsunami, were found in the deposits; (3) Cluster analyses of the geochemical data acquired from the SY03 core by the portable XRF distinguished the paleotsunami deposits on the south Miyazaki plain. Furthermore, we also compiled the geochemical data of samples from the Shizuoka (central Japan), Sendai (Pacific coast of northeast Japan), and Miyazaki plains. Increases in Ti-normalized values (e.g., Sr/Ti) were found in these paleotsunami deposits. Our studies indicate that geochemical approaches are suitable for the characterization and exploration of paleotsunami deposits on the several coastal areas of Japan.

Existence of a continental-scale river system in eastern Tibet during the late Cretaceous\u2013early Palaeogene

The establishment of continental-scale drainage systems on Earth is largely controlled by topography related to plate boundary deformation and buoyant mantle. Drainage patterns of the great rivers in Asia are thought to be highly dynamic during the Cenozoic collision of India and Eurasia, but the drainage pattern and landscape evolution prior to the development of high topography in eastern Tibet remain largely unknown. Here we report the results of petro-stratigraphy, heavy-mineral analysis, and detrital zircon U-Pb dating from late Cretaceous–early Palaeogene sedimentary basin strata along the present-day eastern margin of the Tibetan Plateau. Similarities in the provenance signatures among basins indicate that a continental-scale fluvial system once drained southward into the Neo-Tethyan Ocean. These results challenge existing models of drainage networks that flowed toward the East Asian marginal seas and require revisions to inference of palaeo-topography during the Late Cretaceous. The presence of a continent-scale river may have provided a stable long-term base level which, in turn, facilitated the development of an extensive low-relief landscape that is preserved atop interfluves above the deeply incised canyons of eastern Tibet.

Depositional mode and Provenance of Kopili sandstones from parts of Dima Hasao District, Assam, NE India: Evidence from Grain size distribution and Heavy mineral assemblage

This study presents a record of the depositional mode and provenance of the Kopili sandstones outcropped in and around Umrangso, the Dima Hasao district of Assam, India using proxies such as grain size and heavy mineral study. The Grain size study reveals that the sandstones of the Kopili formation consist predominantly of fine-grained sands mixed with medium sands. The grain size statistical parameters divulge that the sandstones are characterized mostly by moderately sorted sands, coarse skewed to near symmetrical, leptokurtic to extremely leptokurtic nature. The frequency distribution curves reflect mostly bimodal as well as polymodal distribution of sediments. The Linear Discriminant Function analysis indicates shallow marine beach sub environment in agitated water depositional condition for the Kopili sediments. The CM pattern discloses that saltation and suspension are the dominant transporting modes. The Heavy mineral analysis discerns that opaques dominate over transparent heavies. Transparent heavies in decreasing order of abundance are zircon, tourmaline, rutile, clinopyroxene, staurolite, hornblende, garnet, chlorite and epidote. The zircontourmaline- rutile (ZTR) maturity index (average 53.15%) discloses sub-mature to mature nature of the Kopili sandstones. The heavy mineral assemblage corroborates their mixed provenance (silicic igneous and metamorphic) for the Kopili sandstones.

Reconstructing environmental signals across the Permian-Triassic boundary in the SE Germanic Basin: A Quantitative Provenance Analysis (QPA) approach

Global tectonic and climatic models for the Permian-Triassic boundary (PTB) are highly debated. One of the most disputed topics is the temperature increase associated with CO 2 emissions generated by the Siberian Trap volcanism and its potential influence on chemical weathering and associated variations in sediment fluxes. By integrating crustal architecture, plate modelling, structural kinematics, and two climatic models, we reconstruct the drainage evolution of Variscan tectonostratigraphic units from the SE portion of the Germanic Basin, from which we also extract the parameters necessary to calculate sediment flux across a time-scale of 28 Ma (Guadalupian-Lower Triassic). We reconstruct the sedimentary response to climatic and tectonic perturbations using Quantitative Provenance Analysis (QPA) and integrate compositional data into a sedimentological framework, paleodrainage and paleoclimatic models. Raman heavy mineral analysis, as well as geochronology and geochemistry of detrital apatite, zircon, and rutile, document variation in drainage lithologies and sediment flux which are controlled by regional extensional tectonics and increasingly humid conditions at the PTB. The sedimentary successions of the SE Germanic Basin record climatic perturbations on a 10 4 years timescale, while the effects of tectonics are visible on a 10 6 years timescale. The interplay of climate, tectonics and lithology, and their effects on sediment production and drainage evolution resulted in changes in sediment flux from 2.3 Mt./yr during the Guadalupian (Capitanian), to 3.80 Mt./yr in the Lopingian (Changhsingian) to 7.44 Mt./yr at the end of the Lower Triassic (Olenekian). The multifaceted workflow provided in this study represents the first step towards more precise reconstructions of sediment routing systems in deep-time and provides the first ground-truthed quantification of sediment flux across the Permian-Triassic Boundary. • Drainage modifications are efficiently identified via Quantitative Provenance Analysis. • Constraining Environmental Signals in deep-time requires paleoclimatic/tectonic models. • Paleodrainage analysis provides the parameters to calculate sediment flux. • Sediment flux increases in the Lower Triassic in response to climate change.

Groundwater Quality Determination from hand-dug wells in Ososo Town, Akoko-Edo North Local Government Area Edo State

&#x0D; &#x0D; &#x0D; Groundwater is water beneath the surface of the earth. The primary source is precipitation from rain, snow, and hail. Groundwater commonly occurs as water that fills pore spaces between mineral or rock grains in sediments and sedimentary rocks. This study is to evaluate the physiochemical characteristics and selected heavy metal levels of Water from Hand Dug Wells in Ososo in Akoko Edo Local Government Area of Edo State, Nigeria. A total of twenty (20) water samples were collected in very clean containers from twenty (20) hand dug wells in Ososo town, and taken to the laboratory immediately for physical, chemical and heavy metal analysis using standard laboratory techniques. The physical analysis results from the study show that depth to ground water is very shallow. Ph was below 7.5. Conductivity varies from 167.8-2120.00/cm. The temperatures were uniform. The ground water is odorless and tasteless. The amounts of total suspended soil (TSS) in all the samples vary from 10–20 ppm. The total dissolved solid content (TDS) concentration for all the samples varies from 132–1320.00 ppm. Total hardness is soft to moderately hard. Total alkalinity values vary between 3.0 to 18.0 ppm. The phenolphthalein value for the sample tested was zero. Chemical analysis results for the cations shows that Calcium (Ca) is one of the most abundant cations in the entire well water samples with concentration varying from 6.4 – 40.0 mg/L. Magnesium (Mg) concentration vary from 2.0 -9.5 ppm. Dissolved Sodium (Na) content values vary from 17.9- 92.5 mg/L. Chemical analysis results for the anions shows that the concentration of sulphate (SO4) ions varies from 93–125 mg/L. The bicarbonate (CO3) concentration in all samples varies from 25.7–90 mg/L. The dissolved nitrites and nitrates concentrations varies from 5.7 – 9.1. Heavy metals analysis shows the concentrations of copper (CU) in the samples range from 0.1 – 0.5 mg/l. The result of the analysis indicates high values of lead (Pb) in nine samples, but lead was not detected in wells 6 and 7. The values for other wells ranged between 0.1-0.2 mg/l. The values for the concentration of chromium (Cr)range from 0.4 -0.89 mg/l. The values of barium (Ba) range from 0.05- 0.3 mg/l. Result from the heavy mineral analysis for Cadmium (Cd) gave an approximate value of 0.2 and below detectable limit in the other wells. The values of Zinc (Zn) range from 0.8 – 11.4 mg/l. The values of Nickel (Ni) range from 0.1–0.5 mg/l.The hand-dug wells in the study area contain free Carbon IV Oxide and the alkalinity of the well water is entirely due to Bicarbonate ions. Sodium, chloride, bicarbonates, calcium, iron, potassium and magnesium are the most abundant. All the dissolved anions in the well water sample are generally below the recommended maximum limits by WHO. Samples also showed high bacteria load which primarily originated from effluent discharge from pit toilets and waste dumps and can constitute health risk on ingestion. Highly populated areas have groundwater with high concentration of dissolved ions and the converse for areas of low population. From the results of the analysis, conclusion is drawn to the fact that, the groundwater chemistry in the study area has been influenced greatly by human activities than the bedrock geology of the area. It is therefore recommended that well location should be at least, 30 m away from any source of contamination such as soak- ways, adequate treatment must be given to well water such as chlorination, boiling to destroy any bacteria and filtration to remove all unwanted/undesirable constituents that may be present, and a policy on land use planning and urban development to guard against indiscriminate setting of wells within the centre of the village should be established. This study has been able to enhance sustainable water development, since the health of inhabitants in a community depends to a large extent on the quality of groundwater supply.&#x0D; &#x0D; &#x0D;

Controlling Factors Analyses of Sediment Dispersal From Source-to-Sink Systems of Lacustrine Rift Basin: A Case Study From Paleogene Shahejie-Dongying Formations of Nanpu Sag, Eastern China

Tectonic activity not only shapes the basic stratigraphic framework of rift basins, but also profoundly affects the sediment dispersal in rift basins. In this study, analyses of heavy mineral assemblages in different periods demonstrate that there are three obvious tectono-sedimentary evolutionary stages (Es3–Es2, Es1–Ed2, and Ed1, respectively) in the Paleogene provenance area of Nanpu Sag, and the volume of sand bodies increases from the bottom of the Paleogene Shahejie (Es) Formation to the top of the Dongying (Ed) Formation in Nanpu Sag. Besides, this study comprehensively utilize the analyses of seismic interpretation, palynology, heavy mineral, and borehole core samples to investigate the controlling factors of sediment dispersal in the rift basin. The assemblages of heavy minerals in different periods reflect the rock composition and catchment area of different provenance areas, and their vertical differences reflect the evolution process of the provenance area and reflect the uplift-denudation process of the provenance area. The results reveal that the synergy of the evolution of tectonic activity and the adjustment of topographical evolution are the main controlling factors of sediment dispersal in Nanpu Sag, while climate change is not the main controlling factor. We conclude that an increased sediment supply rate in the long term reflects the control of tectonic activity on basin topography, rather than climate fluctuations. The differences in morphological modification result in differential sediment dispersal, which is principally related to the differential extrusion of the fault system. The catchment area and provenance distance adjustment is evidenced by the vertical changes of heavy mineral characteristics of single-well and interaction and linkage of boundary faults, and the adjustment of topography evolution. A consideration is that the interaction and linkage of boundary faults and complex subsidence history are multi-directional, and differential evolution of provenance area is universal in lacustrine rift basins, all of this highlights the adjustment of sediment pathways generated by this characteristic of rift basins and emphasizes the importance of controlling factors analyses in understanding differential sediment dispersal that presents in the rift basins. Besides, four sets of sediment dispersal patterns were delineated based on different developmental regions in the rift basin, which are fault segmental point and multi-stage fault terrace, single-stage fault terrace and axial fault valley, axial fault terrace, and paleo-terrace and axial fault valley, respectively. This study has a certain guiding significance for the prediction of the spatial distribution of sand bodies in the rift basin and the exploration of potential oil and gas targets in the rift basin.

Petrography and heavy minerals analysis for recognition of the depositional history of the Wahiba Sand Sea, Sultanate of Oman

Petrography and heavy minerals analysis for recognition of the depositional history of the Wahiba Sand Sea, Sultanate of Oman

Catastrophic beach sand losses due to erosion from predicted future sea level rise (0.5–1.0 m), based on increasing submarine accommodation spaces in the high-wave-energy coast of the Pacific Northwest, Washington, Oregon, and Northern California, USA

The U.S. Pacific Northwest (PNW) coastline (1000 km) has been analyzed for conditions that could impact beach erosion from potential near-future (100 year) sea level rise (SLR). Heavy mineral analysis of river, beach, and shelf samples (n = 105) establish the sources of the beach deposits. River bedload discharge and intervening estuarine sinks for river sand supplies (n = 31) were normalized to the one century time interval. Twenty-six subcell beaches (657 km in combined length) were surveyed (153 profiles) for beach sand widths (20–412 m) and sand cross-sectional areas (20–1810 m2) above wave-cut platforms and/or 0 m tidal datum. Cross-sectional areas were multiplied by beach segments to yield subcell beach sand volumes (0.4 × 106 m3–35.8 × 106 m3 ± 20% uncertainty). Innermost-shelf profiles were measured for distance to the 100-year depth of closure (30 m) to digitize the areas of inner-shelf accommodation space. Both innermost-shelf and estuarine accommodation space volumes for beach sand displacements were established for 0.5 and 1.0 m SLR. The existing subcell beach sand volumes and computed new beach sand supplies (rivers and longshore transport) were subtracted from the estimated sand volumes lost to submarine accommodation spaces to establish potential beach sand deficits from near-future SLR. Of the 26 surveyed active-beaches, some 60% and 80% (by length) are predicted to be lost, respectively, from the 0.5 m and 1.0 m SLR or equivalent littoral sand sedimentation in submarine accommodation spaces. Projected losses reach 90% for all PNW beaches (~900 km total length) from 1.0 m SLR. The computed beach sand deficits are used to estimate soft-sand retreat distances or erosional beach step backs (50–590 m ± 35% uncertainty) in unrevetted barrier spit and beach/dune deflation plains from 1.0 m SLR. Such empirical accommodation space analyses should have worldwide relevance to predicting beach erosion from near-future SLR.

Deep- versus shallow-marine sandstone provenance in the mid-Carboniferous Clare Basin, western Ireland

In a source-to-sink sedimentary system, multiple processes have the potential to modify the sediment composition during sediment generation at the source, through transport, deposition and burial. To investigate these issues, a multi-proxy provenance study of deep-water and shallow-marine sandstones from the mid-Carboniferous Clare Basin was undertaken, utilizing zircon and apatite U–Pb geochronology, heavy mineral analysis (including apatite trace element data) and petrography. Data from the deep-water submarine fans show a similar provenance signal to the shallow-marine sandstones. Data from across the Clare Basin stratigraphy indicate that sands were probably and consistently derived from the south and SW, with a portion of the detritus being recycled from Old Red Sandstone basins to the south. The provenance signal, however, shows spatial and temporal variations across the basin that are explained by fluctuations in the amount of recycled sediments and are linked with the evolving Variscan Orogenic Belt. Heavy mineral data from both shallow-marine and deep-water sandstones suggest a basin configuration with a delta system feeding directly into the deep basin. Supplementary material: Figures S1–S4 and Tables S1–S8 are available at https://doi.org/10.6084/m9.figshare.c.5446739

Regional multi-sources of Carboniferous karstic bauxite deposits in North China Craton: Insights from multi-proxy provenance systems

The sources of karstic bauxite are complex and have not been so far addressed by multi-proxy provenance studies that interrogate bauxite sources. The Carboniferous bauxite in the North China Craton, which is the largest karstic bauxite area in the world, contains considerable quantities of detrital heavy minerals, including zircon, rutile, tourmaline, and moissanite, allowing multi-proxy provenance studies. In this study, geological, mineralogical, geochemical analyses, and detrital heavy mineral analyses were conducted for the Jiagou and Kuancaoping bauxite deposits located in the southern and northern parts of the North China Craton, respectively. Coupled with previously published geological, geochemical, and detrital mineral data, this study aims to thoroughly clarify the provenance of karstic bauxites in the North China Craton. In general, the ore-bearing rock series contains three units: lower iron-bearing claystone consisting of illite, chamosite, and goethite; middle bauxite ore dominated by diaspore, kaolinite, illite, chamosite, and anatase; and upper bauxitic claystone composed of kaolinite, diaspore, and anatase. Immobile trace element ratios and Rare Earth Element patterns of the bauxites throughout the North China Craton revealed that the lower iron-bearing claystone was autochthonous and directly sourced from the underlying limestone. The isotope data of detrital zircon along with chemical compositions and morphological features of detrital rutile, tourmaline, and moissanite in the bauxite ores revealed that the bauxite ore and bauxitic claystone were mainly para-allochthonous and derived from regional multi-sources. The multi-sources origin is also shared by other karst bauxites in the world. The results indicate that the bauxite deposits in the northern and southern parts of the North China Craton have distinct source materials. The provenance of the bauxite in the northern part of the North China Craton is mainly from the northern margin craton orogenic belt and the adjacent intraplate paleo-uplifts, whereas in the southern part, it is dominated by the North Qinling orogenic belt and the nearby paleo-uplifts. Consequently, the Carboniferous karstic bauxites in the North China Craton are characterized by the autochthonous origin of the lower iron-bearing claystone and the para-allochthonous origin of the upper bauxite ore and bauxitic claystone. This clearly illustrates the dependence of provenance information on mineral proxy choice and underlines the preponderance of multiproxy provenance studies to solve the complex source issue of karst bauxites in North China Craton.