Evolving Earth最新文献

{"title":"Phase equilibria constraints on the stability of garnet in mafic granulite: An example from Karimnagar granulite terrain, Eastern Dharwar Craton, India","authors":"Praveen Chandra Singh ,&nbsp;Divya Prakash","doi":"10.1016/j.eve.2024.100035","DOIUrl":"10.1016/j.eve.2024.100035","url":null,"abstract":"<div><p>Phase equilibria modeling becomes a widely accepted tool to constrain the <em>P-T</em> conditions experienced by the metamorphic terrain because of its advantage over the earlier methods e.g., conventional methods and petrogenetic grids. In this study, garnet stability in the mafic granulite has been examined in response to bulk composition and <em>P-T</em> conditions. Karimnagar granulite terrain (KGT) consists of garnet-free mafic granulite along with garnet-bearing metapelite and silica deficient Mg-Al granulite as an enclave within granite gneiss. Mafic granulite consists of amphibole, orthopyroxene, clinopyroxene, and plagioclase with a minor modal amount of biotite and quartz. Mafic granulite has experienced three distinct metamorphic stages: (a) prograde stage defined by inclusions of minerals like amphibole and quartz within the orthopyroxene and augite, (b) peak stage characterized by coarse grain association of amphibole, orthopyroxene, augite, plagioclase, and minor quartz, (c) the retrograde stage illustrated with coronal growth of amphibole over orthopyroxene and augite. The phase equilibria diagrams were calculated in the Na₂O-CaO-K₂O-FeO-MgO-Al₂O₃-SiO₂-H₂O-TiO₂-O₂ (NCKFMASHTO) model system using bulk rock compositions. Our results show that mafic granulite of the study area has achieved the highest <em>P-T</em> condition of 7 kbar and 800 °C and followed a clock-wise metamorphic trajectory. The calculated <em>P-T</em> pseudosection for two samples indicates the stability of garnet varies between 7.5 and 9.5 kbar at 800 °C. The calculated P-Mo pseudosection (at 800 °C) illustrates the lower stability limit of garnet further goes down with the increase in Al₂O₃ and FeO in the bulk composition.</p></div>","PeriodicalId":100516,"journal":{"name":"Evolving Earth","volume":"2 ","pages":"Article 100035"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2950117224000050/pdfft?md5=c341b694048740685a04de7baa1e1c4a&pid=1-s2.0-S2950117224000050-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142157874","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of nighttime lights over the cities of Cape Town, Durban and Johannesburg, South Africa","authors":"Zandile Mncube ,&nbsp;Sifiso Xulu ,&nbsp;Nkanyiso Mbatha","doi":"10.1016/j.eve.2024.100046","DOIUrl":"10.1016/j.eve.2024.100046","url":null,"abstract":"<div><div>Remote sensing of nighttime light (NTL) offers a unique and practical means of assessing human developments through snapshots of nocturnal lighting captured from space. The Visible Infrared Imaging Radiometer Suite (VIIRS) Day/Night Band (DNB) is one of the widely used NTL products and is now publicly available on Google Earth Engine (GEE), which allows accelerated analysis using different geospatial approaches. Here, we perform a comparative trajectory analysis of NTL over the three largest cities of South Africa between 2014 and 2023, and project the changes for 2027 based on Markov chain analysis. Our results show that the NTL increased steadily for the city of Durban (from 27.93 nW cm⁻².sr⁻¹ in 2014 to 29.45 nW cm⁻².sr⁻¹ in 2023) but decreased in the cities of Cape Town (from 32.30 nW cm⁻².sr⁻¹ in 2014 to 31.14 nW cm⁻².sr⁻¹ in 2023) and Johannesburg (from 52.19 nW cm⁻².sr⁻¹ in 2014 to 46.82 nW cm⁻².sr⁻¹ in 2023). The unstable power supply of South African cities can affect the NTL data. In addition, from our results, a similar pattern for each of these cities is observed to be in line with load shedding events in the country, especially for Cape Town and Johannesburg. Regarding the spatiotemporal distribution of the NTL, the central areas have medium to high radiance and have been spreading to the periphery of the cities since 2014. Moreover, land use and land cover (LULC) analysis reveals that developed urban areas, shown by dense built-up areas, coincide with the locations of medium and high NTL radiances. The assessment of NTL changes across low, medium, and high classes indicates a stable configuration with no large changes between classes; this is also observed on the spatial projection of NTL for the year 2027. Our results shed light on NTL mapping in large cities, an area that is constantly evolving due to new developments in remote sensing.</div></div>","PeriodicalId":100516,"journal":{"name":"Evolving Earth","volume":"2 ","pages":"Article 100046"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142748254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Petrogenesis of paleocene flood basalt sequence and interlayered sedimentary successions in the Mannar Basin – Offshore Sri Lanka (Northern Equatorial margin of the Indian Ocean)","authors":"S. Karunarathne ,&nbsp;P.L. Dharmapriya ,&nbsp;W.M.H.M. Wijesinghe ,&nbsp;M. Hellers ,&nbsp;A.U. Wijenayake ,&nbsp;H.M.T.G.A. Pitawala ,&nbsp;E.K.C.W. Kularathna","doi":"10.1016/j.eve.2024.100047","DOIUrl":"10.1016/j.eve.2024.100047","url":null,"abstract":"<div><div>The Mannar Basin is a rift basin formed during the breakup of Gondwana, comprising sedimentary deposits from multiple cycles. Exploration for hydrocarbons has uncovered igneous sequences distributed throughout the basin's sedimentary sequences. These sequences exhibit geochemical characteristics, typical for flood basalts formed during a series of eruptions from 60 to 62 Ma. Previous studies have focused on the petroleum system, tectonostratigraphy, lithostratigraphy, and the paleo-environmental setting, therefore, little was known about the petrogenesis of this flood basalt sequence. This study investigates the petrogenesis of the flood basalt sequence, focusing on crystallization temperature, source magma characteristics, and the nature of magma fractional crystallization. Additionally, it examines the mineralogical characteristics, including clay minerals, of the interstratified sedimentary layers to interpret their origins—an area that has not been previously studied in depth. Petrographic thin sections were prepared from unwashed drill cuttings taken from a depth of 4000–4200 m in the Barracuda petroleum exploration well. A detailed petrographic study was conducted on these samples to investigate the petrogenesis. Additionally, electron probe microanalysis (EPMA) was performed to determine the mineral chemistry of the basalt and interstratified sedimentary rock samples. The basalts are primarily composed of plagioclase (An_62-82) and clinopyroxene (mostly augite), with minor occurrences of orthopyroxene (En_54-67) and ulvöspinel. Only the lower-most basalt layers (4200–4210 m) contain olivine (Fo_56-71). High-Al orthopyroxenes were observed in the shallower sequence. Mineral zoning and mineral chemical variations record fractional crystallization of the mafic magma. Together, these minerals reflect a complex magmatic evolution, where, initially, high-temperature conditions prevailed, followed by differentiation and fractional crystallization; a transition from primitive to more evolved conditions. Geothermometric calculations indicate crystallization temperatures of the basalt varying from 1330 to 1340 °C, typically associated with mantle-derived magmas and representing high-temperature magmatic processes.</div><div>The interlayered sedimentary rocks within the basalt sequence are dark-coloured and consist of weathered feldspar and clinopyroxenes, with minor quartz and calcite. Powder x-ray diffraction (XRD) analyses reveal the presence of clay minerals such as smectite, antigorite, attapulgite, and chlorite in these sedimentary rocks. While unpublished reports suggest that the interlayered rocks are sandstones and shales (based on gamma-ray log data), these analyses indicate that they are volcaniclastic sediments resulting from the weathering of individual layers of the flood basalt sequence after their eruption.</div></div>","PeriodicalId":100516,"journal":{"name":"Evolving Earth","volume":"2 ","pages":"Article 100047"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142748255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Crystallographic study of vertebrate fossils from the Central Narmada valley, India","authors":"Sakina Abdeali Halvadwala,&nbsp;Prateek Chakraborty","doi":"10.1016/j.eve.2024.100033","DOIUrl":"10.1016/j.eve.2024.100033","url":null,"abstract":"<div><p>The Narmada River originates in eastern Madhya Pradesh near Amarkantak (200 40′ N, 81 46′ E), travels through Madhya Pradesh, Maharashtra, and Gujarat before emptying into the Gulf of Cambay in the Arabian Sea, close to Baruch in Gujarat. Numerous fossil discoveries in the region include various mammals, reptiles, fishes, amphibians, and molluscan shells. In addition to being a rare mid-continental location in the Old World, the Narmada Valley has traditionally served as a line delineating Northern and Southern India. This valley has produced countless animal fossils as well as a few human fossils. This has been a crucial route for the movement of both faunal migrations from the north to the south and the transmission of the monsoons from the southeast to the northwest. The present work examines the crystallization index of the faunal fossils from three (Barmanghat,Talayyaghat,Devakachar) localities in the Central Narmada valley falling within the region of Madhya Pradesh. Fossil samples were subjected to X-Ray diffraction in order to calculate the Crystallization index as a direct indicator of the degree of fossilization. The materials of Narmada river valley have been studied extensively by previous scholars; however, this study is first attempt to study the fossils using scientific technique such as XRD.</p></div>","PeriodicalId":100516,"journal":{"name":"Evolving Earth","volume":"2 ","pages":"Article 100033"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2950117224000037/pdfft?md5=38d03fb156794efef7028cdbebe342fa&pid=1-s2.0-S2950117224000037-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142136341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Morphospecies of potentially toxic cyanobacterium Microcystis - A review on colony formation and its global distribution","authors":"Renju Mohan ,&nbsp;Afnitha K.H ,&nbsp;Ajayakumar P ,&nbsp;Lathika Cicily Thomas ,&nbsp;K.B. Padmakumar","doi":"10.1016/j.eve.2024.100049","DOIUrl":"10.1016/j.eve.2024.100049","url":null,"abstract":"<div><div>The increased occurrence of toxic blooms of <em>Microcystis</em> is emerging as a global concern due to the health implications and associated water quality issues. <em>Microcystis</em> are single-celled ubiquitous cyanobacteria capable of forming colonies of different morphologies in various eutrophic water bodies, including freshwater, estuaries and marine systems. Their distribution and severity have increased during past decades, contributed by factors like warmer temperatures, climate change, eutrophication and other hydrological changes. They form colonies of varying shapes and sizes depending on the type of species and environmental factors. This cyanobacterial genus consists of more than 50 distinct morphological variants, mainly based on their physical characteristics like cell shape, size, colony arrangement etc. However, their greater morphological variations and phenotypic plasticity often complicate their morphological identification. Studies regarding their morphospecies are thus crucial for improved taxonomic classification, identifying the major bloom-forming species and their ecological impacts. This review has attempted to provide a brief knowledge about some of the common morphospecies of <em>Microcystis</em>, its colony formation and distribution worldwide.</div></div>","PeriodicalId":100516,"journal":{"name":"Evolving Earth","volume":"2 ","pages":"Article 100049"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142757075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geochemical modeling of diagenetic reactions between albitization of K-feldspar and plagioclase feldspar in sandstone reservoirs under the influence of CO2 partial pressure","authors":"Marcos Antonio Klunk ,&nbsp;Tiago Jonatan Girelli ,&nbsp;Soyane Juceli Siqueira Xavier ,&nbsp;Farid Chemale Jr ,&nbsp;Renzo D'souza ,&nbsp;Mohuli Das ,&nbsp;Sudipta Dasgupta","doi":"10.1016/j.eve.2024.100042","DOIUrl":"10.1016/j.eve.2024.100042","url":null,"abstract":"<div><div>Diagenetic albitization has been observed in sedimentary basins around the world. This process significantly changes the original composition of sandstones and the chemistry of the formation waters under the influence of partial pressure of CO₂. The transformation of detrital feldspars into albite is considered a crucial diagenetic process in the Gulf Coast and North Sea reservoirs. Earlier studies suggest that plagioclase albitization typically happens before that of K-feldspar. In the Gulf Coast's Frio Sandstone, located in the Upper Oligocene at depths between 900 and 2400 m, detrital plagioclase is often dissolved and replaced by albite, while K-feldspar mostly dissolves without much substitution. Similarly, in the North Sea reservoirs, especially in the upper section of the Upper Triassic Lunde Formation at depths beyond 2900 m, plagioclase tends to undergo albitization, whereas K-feldspar remains largely unaffected or experiences minimal transformation. This research focuses on analyzing the differences in the albitization patterns of detrital and K-feldspar plagioclase through the KINDISP and Geochemist's Workbench (GWB) geochemical modeling tools, aiming to compare them. These diagenetic processes are crucial for reservoir geology, as they influence the concentration of silica in water, which, in turn, affects quartz cementation. This study aims to explore the variations in the albitization behavior of detrital and K-feldspar plagioclase using the KINDISP and Geochemist's Workbench (GWB) geochemical models and conduct a comparative analysis between them. Understanding these diagenetic reactions becomes relevant for reservoir geology analysis, as such phenomena control the aqueous silica concentration to some extent, which is consequently reflected in the quartz cementation. The dissolution of plagioclase and K-feldspar releases silica into the pore fluids. As the concentration of silica in the fluid increases, it leads to the precipitation of quartz as overgrowths on detrital quartz grains, a process known as quartz cementation. This was observed particularly in simulations involving temperature increases up to 150 °C, where the equilibrium between albite and anorthite was closely linked to the stability of quartz (Ben et al., 1993). The removal of feldspar through albitization reduces porosity and permeability but contributes silica to the system, which promotes quartz cementation. This, in turn, decreases the reservoir quality by filling pore spaces with secondary quartz, reducing the rock's ability to store and transmit fluids. Thus, the study highlights the importance of these diagenetic processes in reservoir evaluation, as the balance between feldspar dissolution and quartz cementation ultimately controls reservoir properties.</div></div>","PeriodicalId":100516,"journal":{"name":"Evolving Earth","volume":"2 ","pages":"Article 100042"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142532618","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seismic risk assessment using integrated MCDM method in West Bengal, India","authors":"Monalisa Malakar ,&nbsp;Sukanta Malakar ,&nbsp;Mohd Sayeed Ul Hasan ,&nbsp;Abhishek K. Rai ,&nbsp;Vijay K. Kannaujiya","doi":"10.1016/j.eve.2024.100036","DOIUrl":"10.1016/j.eve.2024.100036","url":null,"abstract":"<div><div>Earthquakes are one of the natural hazards that threaten human lives and properties. Consequently, seismic risk assessment plays a significant role in disaster mitigation. This study estimates seismic risk in West Bengal, India, by integrating the two multi-criteria decision-making (MCDM) models: analytical hierarchy process (AHP) and Entropy. Integrated AHP-Entropy is used to determine vulnerability, seismic hazard, and coping capacity. The seismic risk was then assessed by integrating the thematic information of vulnerability, seismic hazard, and coping capacity. The results show that about 19% of the total area and 70% of the total population in West Bengal may be at very high seismic risk. The result is validated through a receiver operating characteristic curve, displaying satisfactory performance in seismic risk estimation. The findings of this study may help governmental agencies identify seismic-risk zones and establish seismic hazard plans in advance against any potential threat in the study region.</div></div>","PeriodicalId":100516,"journal":{"name":"Evolving Earth","volume":"2 ","pages":"Article 100036"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2950117224000062/pdfft?md5=58e6091ddcad46fef6e94cd478244d26&pid=1-s2.0-S2950117224000062-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142316256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Potential of pine forest in controlling soil erosion in Himalayan region - Investigation using fallout radionuclide (137Cs) measurements","authors":"Anu David Raj ,&nbsp;Suresh Kumar ,&nbsp;Sankar Mariappan ,&nbsp;K.R. Sooryamol ,&nbsp;Justin George Kalambukattu","doi":"10.1016/j.eve.2024.100031","DOIUrl":"10.1016/j.eve.2024.100031","url":null,"abstract":"<div><p>The Himalayas possess a distinctive topography owe to the dynamic interplay of tectonic activity, geological erosion and sedimentation, glacial processes, and climatic influences over the millions of years. The rugged, steep terrain and poor land management make it more prone to water erosion, negatively impacts the soil, affecting the goods and services supported by the soil ecosystems. Traditional methods used in soil erosion assessment face limitations when dealing with topographically complex hillslopes. The use of Fallout Radionuclide (FRN) -¹³⁷Cs provides a feasible alternative for measurement of soil erosion in the region with such topography. However, there is lack of ¹³⁷Cs-based soil erosion studies in the north-west Himalayas. Pine (<em>Pinus roxburghii</em>) is the predominant forest type in the Himalayas, offering numerous benefits to both natural ecosystems and human beings. In this study, we selected a typical steep hillslope covered with pine forest in the Himalayas for soil erosion assessment. The study measured ¹³⁷Cs reference inventory of 1409 Bq m⁻² in the landscape. Importantly, the concentration of ¹³⁷Cs along the hillslope positions showed a significant variation attributed to topographic variability. Topographic factors, such as the slope shape and gradient, were identified as the major governing parameters of soil erosion in the hilly and mountainous region. The net soil erosion rate over hillslope positions revealed highest at upper hillslope followed by ridge, middle and valley hillslope positions. The net soil erosion rate under the pine forest ranged from 8.0 to 14.6 t ha⁻¹ yr⁻¹, with an average rate of 9.9 t ha⁻¹ yr⁻¹. Erosion rate over the hillslope positions were found in accordance to the soil loss tolerance limit (SLTL) except for the upper hillslope, indicating it as critical slope position requires to adopt suitable conservation measures. The study signifies the role of the forest in mitigating soil erosion and, in turn, conserving soil resources. The findings provide crucial insights and guidance to land managers and decision-makers, emphasizing the necessity of conserving and restoring forests in the Himalayas.</p></div>","PeriodicalId":100516,"journal":{"name":"Evolving Earth","volume":"2 ","pages":"Article 100031"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2950117224000013/pdfft?md5=d6b4c238d40ed4ee2b90bdc733d569de&pid=1-s2.0-S2950117224000013-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141623773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reconstruction of avulsion history of the Brahmaputra River: Rare example of a giant braided river course alteration through multi-channel multi-avulsion processes","authors":"MD. Raihanul Islam,&nbsp;Imran Khan,&nbsp;MD. Alifnur Salim,&nbsp;M.D. Musfequzzaman","doi":"10.1016/j.eve.2024.100034","DOIUrl":"10.1016/j.eve.2024.100034","url":null,"abstract":"<div><p>The avulsion scenario of the Brahmaputra has been a debated issue for quite a long time. This study aims to resolve this debate through reconstruction of the avulsion history of the Brahmaputra. We have addressed the processes, timeline and causes of the avulsion. Old maps and images from 1776 to 2023, evidence from contemporary literature and recent studies have been used in our study. We find that the process of creation of the Jamuna was started through capturing the flow of the Brahmaputra by the Jenni during the 1780s. Between 1780 and 1800 the Brahmaputra created two primary avulsion channels upstream and initiated the multi-avulsion process which was completed in the 1880s. The first avulsion channel conveyed the Brahmaputra flow into the Konaie directly and the second avulsion channel diverted the flow captured by the Jenni into the Konaie. Contemporarily, the flow-enriched Konaie switched its flow into the Jenni at downstream through an unnamed channel and the combined flow traveled through the bed of the Jenni before creating the confluence with the Ganges. In the whole process, the Konaie received, inflated and transported the dominant flow of the Brahmaputra and the Jenni became inferior over time. We have introduced a bend migration concept along with local sediment overload to focus on setting up a lower stability threshold of avulsion that led to the eruptive creation of the avulsion channels by a coupled switching mechanism imparted by high monsoonal discharges, avulsion of the Tista into the Brahmaputra and the high-magnitude floods.</p></div>","PeriodicalId":100516,"journal":{"name":"Evolving Earth","volume":"2 ","pages":"Article 100034"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2950117224000049/pdfft?md5=13edd939e0300dd88ea59df5d27aad8c&pid=1-s2.0-S2950117224000049-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142117415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bonebed amber deposits: A review of taphonomy and palaeontological significance","authors":"Pierre Cockx ,&nbsp;Ryan C. McKellar","doi":"10.1016/j.eve.2024.100032","DOIUrl":"10.1016/j.eve.2024.100032","url":null,"abstract":"<div><p>Bonebeds and amber deposits provide a wealth of palaeontological information allowing palaeobiologists to reconstruct ancient ecosystems in great detail. It is a common view that these two sources of data rarely intersect in the fossil record, owing to distinct taphonomic pathways. Nonetheless, the past decades have seen an increasing number of bonebed amber deposits reported and investigated, suggesting that some depositional environments might provide the appropriate conditions for preserving plant material and bones. By reviewing the current knowledge of the taphonomy of amber deposits and that of bonebeds, and through examination of a series of Cretaceous deposits in North America and Europe, we identify a taphonomic window that permits the long-term preservation of both materials. This synthesis allows us to provide some keys for bonebed amber prospecting, which will hopefully lead to additional finds in the field. We also review the main findings of the first comprehensive studies of bonebed amber deposits which focus on the amber assemblage, the chemistry of the fossil resin, and its stable isotopic composition, to demonstrate the utility of combined studies. This approach enables palaeobiologists to reconstruct past forest habitats by (<em>i</em>) exploring the faunal communities (especially, arthropod communities) of the forests, (<em>ii</em>) identifying the dominant source tree, (<em>iii</em>) identifying the ecological conditions, and (<em>iv</em>) characterizing the palaeogeography of the region. These findings show that amber represents a source of complementary data within bonebeds and can help achieving a better knowledge of past terrestrial habitats.</p></div>","PeriodicalId":100516,"journal":{"name":"Evolving Earth","volume":"2 ","pages":"Article 100032"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2950117224000025/pdfft?md5=892761fadd4e77ade4916ff31538a9ef&pid=1-s2.0-S2950117224000025-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142021101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}