Secondary Migration Research Articles

Utilization of Pyrrolic Compounds as Indicators of Secondary Migration for Woodford Oils in the Anadarko Basin, Oklahoma, USA

Utilization of Pyrrolic Compounds as Indicators of Secondary Migration for Woodford Oils in the Anadarko Basin, Oklahoma, USA

Migration aspirations in relation to border closures, employment opportunities and risk-taking attitudes: lessons from an online survey experiment

ABSTRACT This article investigates the effect of structural and individual factors on migration aspirations in a secondary migration context. Through an online survey experiment conducted with Syrian migrants (N = 551) living in Turkey, we unpack factors explaining aspirations to stay and move onward from the current country of residence. The findings indicate that open borders alone do not compel migrants to move onward. Instead, employment opportunities in their current residence play a crucial role in shaping aspirations to stay put. Moreover, individuals inclined to take risks are more likely to migrate, even when strict border controls are in place. By highlighting the question of what motivates migrants to stay as well as to move onward, this research emphasizes individual differences in forming migration aspirations and contributes to migration aspirations literature in the secondary migration context.

Settling beyond big cities: A scoping review of the Canadian literature on immigration to rural and smaller communities

AbstractNewcomers are living and working across rural and smaller communities in Canada. However, immigration research and policy are overwhelmingly focused on large, urban centres. Responding to this knowledge gap, this article presents the results from a scoping review of the Canadian literature on immigration outside of Canada's largest cities. An analysis of 90 studies reveals several key trends in the literature related to the geographic focus and themes addressed. The results of the review demonstrate that the majority of studies focus on regions with a high population density that are in close proximity to major urban centres, thus revealing a gap in knowledge regarding settlement across more rural and northern parts of the country. Issues related to settlement services, employment opportunities, welcoming communities, public policy, infrastructure, and retention and secondary migration were the most addressed themes across the literature and represent the diversity of rural Canada. In response to these findings, we conclude with a discussion of the potential opportunities for future research and policy change.

Influence of faults on late-stage migration of methane-rich gas in a major unconventional hydrocarbon accumulation: Montney Formation, western Canada

Faults are thought to act as barriers or conduits for intraformational hydrocarbon migration within unconventional low-permeability hydrocarbon accumulations. However, well-documented studies substantiating this phenomenon at the regional-scale are scarce. Here, we use an extensive molecular and isotopic dataset for produced-gas samples (n = 562) from the Montney unconventional hydrocarbon accumulation of northeast British Columbia to show that regional-scale secondary migration of methane-rich gas was significantly influenced by the distribution and orientation of faults. Cross-plots using iC4/nC4, δ13C ethane and δ13C propane exhibit single coherent distributions, suggesting that the C2+ components of most of these gases share interrelated histories of generation, maturation and primary migration. Conversely, cross-plots using gas dryness and δ13C methane against other selected gas parameters demonstrate geographic differentiation, with samples from the southeastern part of the study area generally exhibiting elevated molecular concentration and isotopic enrichment of methane compared to the samples from the northwestern part of the study area. The compositional and isotopic enrichment of methane in the southeastern samples signify significant late-stage secondary migration of highly mature methane-rich gas from deeper zones to shallower zones, and mixing with in-situ hydrocarbon fluids of lower thermal maturity. Previous structural mapping documents the presence of numerous subsurface thrust-faults related to the Cordilleran orogeny in the northwestern area, while these features are entirely absent in the southeastern area. Consequently, we conclude that thrust-faults, with accompanying clay-rich gouges, formed effective en-echelon barriers to the late-stage secondary migration of methane-rich gas in the northwestern area and prevented substantial mixing of hydrocarbon fluids.

Molecular dynamics simulations and experimental studies on low-temperature growth of GaN

Growth mechanisms of (0001) wurtzite GaN films at low temperature are investigated by molecular dynamics simulations and experiments. The crystallization properties of GaN films deteriorate dramatically at low temperature due to the limited energy available for atomic surface migration and incorporation into the perfect lattice sites. In our simulation, growth interruption stage is periodically introduced and the as-deposited GaN films are treated with energy-carrying argon ions at this stage. The surface atoms located at the weak binding sites can acquire energy from the argon ions for secondary migration and incorporation into the perfect lattice sites. As a result, the crystallization properties of GaN films are significantly improved. GaN films are experimentally grown on sputtered AlN/sapphire substrates at 600 °C via inductively coupled plasma metal organic chemical vapor deposition along with periodic argon plasma treatment. The as-deposited film acquires energy from the plasma, leading to significant improvement of the crystalline properties. The surface morphology of the GaN film demonstrates a noticeable smoothing effect, with an evident increase in grain size from submicron to micron level. Additionally, GaN film with the optimized surface morphology exhibits high c-axis and in-plane orientations, and the full width half maximums of (002) and (102) x-ray diffraction rocking curves are 0.25° and 0.32°, respectively. These results provide effective guidance for the growth of GaN films at low temperature.

Syn-tectonic fluid-flow and fault-fluid interaction along bedding-parallel thrust faults: Evidence from the frontal zone of the Chuandong-Xiangexi fold-and-thrust belt in central South China

Fluid-flow within tectonic belts and fault-fluid interaction are fundamental and controlling factors of large thrust belt evolutions, formation of mineral deposits in the upper crust and the ductile shear deformation in the middle crust. In central South China, a large Chuandong-Xiangexi fold-and-thrust belt and long-distance displaced thrust faulting are developed, but their formation mechanism is still in debate. In particular, the evolution of fluid-flow and fault-fluid interactions in this fold-and-thrust belt is still not well constrained. In this study, through detailed structural and microstructural observations together with stable isotope and fluid inclusion analyses, we aim to unravel the deformation characteristics and syn-tectonic fluid-flow along the detachment in the frontal zone of this fold-and-thrust belt. One approximately 30–60 m thick, NW-verging detachment thrust with brittle-ductile deformation and alternating the strongly and weakly deformed zones is identified in the Lower Permian bioclastic and argillaceous limestones. The strongly deformed zone is characterized by tectonic lenses, fault gouge, calcite veins, S–C fabric, and foliated fault rocks/gouge, while the weak deformation zone is marked by scattered fractures without calcite veins and weakly deformed tectonic lenses. The fluids within the thrust faults originate from formation waters (saline fluids or brines) in a closed system, evidenced by the δ18O values, the 87Sr/86Sr ratios, the hydrocarbon-bearing fluid inclusions characterized by moderate salinity (10–14 wt% NaClequiv.) and moderate-high homogenization temperatures (∼160–350 °C). In the hanging wall of the Huangyingshan fault, the fluids involved in the thrusting processes are most likely brines derived from Middle and Lower Triassic carbonate aquifers. While in the footwall, the fluids are likely brines derived from Cambrian evaporitic aquifers. These findings on the detachment thrust fault zone could provide valuable constraints on the conduit and distance of hydrocarbon secondary migration for exploring the potential of large-scale hydrocarbon accumulation in the Chuandong-Xiangexi fold-and-thrust belt.

Complications in the use of peripherally inserted central catheter associated with peripheral intravenous therapy: retrospective cohort.

to analyze the occurrence of difficulty in the peripheral insertion of the central catheter and the presence of complications in the use of this device in hospitalized adults who received peripheral intravenous therapy through a short peripheral intravenous catheter and to identify whether there is an association between peripheral intravenous therapy and the presence of complications in the use of the peripherally inserted central catheter. retrospective cohort, with patients aged 18 years or over, in a tertiary teaching hospital, with a peripherally inserted central catheter, who had at least one previous short peripheral intravenous catheter. Data were analyzed using descriptive statistics and Poisson regression. the sample consisted of 76 patients. There was an association between difficulty in the insertion procedure and number of punctures (p<0.01) and insertion in the external jugular vein compared to the upper limbs (p<0.01). The insertion site was also associated with the removal of the peripherally inserted central catheter due to complications in the robust analysis of variance (p=0.02). No associations were identified between: difficulty inserting the device and time on peripheral intravenous therapy (crude model p=0.23; adjusted model p=0.21); difficulty in insertion with administration of irritating and vesicant medication (crude model p=0.69; adjusted model p=0.53); complication in the use of peripherally inserted central catheter and time of peripheral intravenous therapy (crude and adjusted models p=0.08); and secondary migration of the catheter tip with the device insertion site (p=0.24). it was possible to identify secondary migration as one of the main complications, resulting in premature removal of the device. Furthermore, the greater the number of puncture attempts to insert the PICC, the greater the difficulty in inserting it. Insertion into the external jugular vein was recurrent, with a higher risk of removal due to complications in relation to the upper limbs.

New immigration destinations in Sweden: Migrant residential trajectories intersecting rural areas

AbstractThis paper aims to examine the residential trajectories of immigrants that intersect rural areas in Sweden. It adds to the literature on new immigration destinations (NIDs) and addresses the need to include migration routes intersecting rural areas, immigrants’ secondary migration patterns and temporal dimensions of migration, as well as the multiplicity of migrants in such destinations. We examine whether NIDs have emerged in Sweden and immigrants’ subsequent internal mobility from such areas and its determinants. Employing sequence analysis to full‐population register data, we identify typical migration pathways. According to the results, NIDs are an emerging phenomenon in rural and small‐sized cities in Sweden. We find limited support for the Swedish discourse that the diverse groups of rural migrants leave soon after arrival; also, those leaving are not doing so for labour market–related reasons, nor are they heading for metropolitan areas. We suggest that NIDs offer an important contribution to understanding migration patterns.

A new method of the hydrocarbon secondary migration research: Numerical simulation

A three-dimensional invasion percolation simulation model is introduced and integrated into a novel three-dimensional geological modeling framework based on the “unit element” theory to study secondary hydrocarbon migration. Leveraging the computational efficiency inherent in the invasion percolation theory, the simulation method is effectively applied to basin-scale hydrocarbon migration using finely discretized grids. Sensitivity analysis demonstrates the substantial influence of geological parameters including structural configuration, sedimentary facies, and pressure, on simulation results. Noteworthy observations from this study encompass: (1) The intricate influence of sedimentary facies and petrophysical properties characteristics on hydrocarbon migration and accumulation patterns within structural and lithological traps. Favorable petrophysical attributes in the carrier beds enhance the likelihood of accumulation in the structural traps, while lithological traps are prevalent in less conducive carrier beds. (2) The significant impact of sand bodies exhibiting favorable petrophysical attributes, such as channels, on migration and accumulation profiles. This underscores the necessity of incorporating sedimentary facies and rock attributes into oil and gas resource exploration. (3) The pronounced effects of overpressure magnitude and direction on hydrocarbon migration and accumulation dynamics. (4) Optimal strategies for oil and gas resource exploration necessitate a comprehensive assessment of rock attributes, overpressure considerations, and sedimentary facies. The practical implementation of this methodology is demonstrated in an actual exploration project within China's Junggar Basin. The simulation results closely align with established oil recovery data and facilitate predictive identification of promising exploration areas. This indicates the methodology is applicable to all petroleum systems similar to Junggar Basin. Through practical applications, the development of a scientifically rigorous three-dimensional geological model for the study area, coupled with numerical simulations of oil and gas migration, facilitates the elucidation of accumulation patterns. This approach aids in identifying pivotal factors such as sand body distribution, internal structural composition, permeability attributes, and fracture behavior, which collectively influence oil and gas migration. Furthermore, by correlating insights obtained from oil and gas discoveries in wells, a deeper understanding of carrier bed properties and their geological evolution is attained.

Introducing the role of the municipality of residence in studying the secondary migration of international migrants. Evidence from Lombardy (Italy)

AbstractSecondary internal and international movements of migrants are receiving increasing attention in Europe while research has so far focused on the characteristics of individuals who remigrate or plan to re‐emigrate, the attributes of the place that secondary migrants aim to leave have been less studied compared to other personal characteristics. This knowledge gap is primarily due to the fact that detailed information on the municipality of residence is largely unavailable in nationwide sample surveys. To fill this gap, after considering the time since migrants' arrival in Italy and previous internal mobility, we analyse the relationship between the characteristics of the municipality where migrants live and short‐term migration intentions of return, onward and internal migration in a competing risk framework. We focus on ethnic concentration (community hotspots and coldspots) and classification into central and marginal areas as critical characteristics of municipalities. We used a unique pooled data set that includes seven cross‐sectional surveys conducted between 2010 and 2016 by the Regional Observatory for Integration and Multiethnicity in the Northern Italian region of Lombardy. Municipal characteristics are strongly related to migrants' intentions: migrants who intend to move internally or to a third country are more likely live in urban, suburban, intermediate and peripheral areas and in the mountains. In contrast, the intention to return is not correlated with the characteristics of the municipality. The concentration of co‐nationals is also uncorrelated with short‐term migration intentions. We discuss the limitations of using a concentration indicator to study the relationship with secondary mobility.

Change and stability of migration intentions. Evidence from Italy

AbstractDue to a lack of relevant data, very few empirical studies have examined the changes in and stability of secondary migration intentions. We aim to fill this gap by analysing return migration intentions among international migrants in Italy. Data are drawn from the cross‐sectional SCIF survey conducted by ISTAT in 2011–2012. Our findings reveal that migration intentions at the beginning of the migratory experience tend to differ from those measured at more advanced migration stages (i.e. at the time of the survey). In particular, intentions to return seem less stable than intentions to stay. When confirming intentions to return or remain, critical factors include financial stability, family situation and ties with the country of origin and destination. Additionally, having an Italian partner, a partner living in Italy, and a positive self‐assessed family financial condition are positively associated with transitioning from a temporary plan to a permanent settlement intention.

A fusion of VGG-16 and ViT models for improving bone tumor classification in computed tomography

Background and ObjectiveBone tumors present significant challenges in orthopedic medicine due to variations in clinical treatment approaches for different tumor types, which includes benign, malignant, and intermediate cases. Convolutional Neural Networks (CNNs) have emerged as prominent models for tumor classification. However, their limited perception ability hinders the acquisition of global structural information, potentially affecting classification accuracy. To address this limitation, we propose an optimized deep learning algorithm for precise classification of diverse bone tumors. Materials and MethodsOur dataset comprises 786 computed tomography (CT) images of bone tumors, featuring sections from two distinct bone species, namely the tibia and femur. Sourced from The Second Affiliated Hospital of Fujian Medical University, the dataset was meticulously preprocessed with noise reduction techniques. We introduce a novel fusion model, VGG16-ViT, leveraging the advantages of the VGG-16 network and the Vision Transformer (ViT) model. Specifically, we select 27 features from the third layer of VGG-16 and input them into the Vision Transformer encoder for comprehensive training. Furthermore, we evaluate the impact of secondary migration using CT images from Xiangya Hospital for validation. ResultsThe proposed fusion model demonstrates notable improvements in classification performance. It effectively reduces the training time while achieving an impressive classification accuracy rate of 97.6%, marking a significant enhancement of 8% in sensitivity and specificity optimization. Furthermore, the investigation into secondary migration's effects on experimental outcomes across the three models reveals its potential to enhance system performance. ConclusionOur novel VGG-16 and Vision Transformer joint network exhibits robust classification performance on bone tumor datasets. The integration of these models enables precise and efficient classification, accommodating the diverse characteristics of different bone tumor types. This advancement holds great significance for the early detection and prognosis of bone tumor patients in the future.

Gulong shale oil enrichment mechanism and orderly distribution of conventional– unconventional oils in the Cretaceous Qingshankou Formation, Songliao Basin, NE China

Through the study of organic matter enrichment, hydrocarbon generation and accumulation process of black shale of the Cretaceous Qingshankou Formation in the Songliao Basin, the enrichment mechanism of Gulong shale oil and the distribution of conventional–unconventional oil are revealed. The Songliao Basin is a huge interior lake basin formed in the Early Cretaceous under the control of the subduction and retreat of the western Pacific plate and the massive horizontal displacement of the Tanlu Fault Zone in Northeast China. During the deposition of the Qingshankou Formation, strong terrestrial hydrological cycle led to the lake level rise of the ancient Songliao Basin and the input of a large amount of nutrients, resulting in planktonic bacteria and algae flourish. Intermittent seawater intrusion events promoted the formation of salinization stratification and anoxic environment in the lake, which were beneficial to the enrichment of organic matters. Biomarkers analysis confirms that the biogenic organic matter of planktonic bacteria and algae modified by microorganisms plays an important role in the formation of high-quality source rocks with high oil generation capability. There are four favorable conditions for the enrichment of light shale oil in the Qingshankou Formation of the Gulong Sag, Songliao Basin: the moderate organic matter abundance and high oil potential provide sufficient material basis for oil enrichment; high degree of thermal evolution makes shale oil have high GOR and good mobility; low hydrocarbon expulsion efficiency leads to a high content of retained hydrocarbons in the source rock; and the confinement effect of intra-layer cement in the high maturity stage induces the efficient accumulation of light shale oil. The restoration of hydrocarbon accumulation process suggests that liquid hydrocarbons generated in the early (low–medium maturity) stage of the Qingshankou Formation source rocks accumulated in placanticline and slope after long-distance secondary migration, forming high-quality conventional and tight oil reservoirs. Light oil generated in the late (medium–high maturity) stage accumulated in situ, forming about 15 billion tons of Gulong shale oil resources, which finally enabled the orderly distribution of conventional–unconventional oils that are contiguous horizontally and superposed vertically within the basin, showing a complete pattern of “whole petroleum system” with conventional oil, tight oil and shale oil in sequence.

Migration Processes in Austria: Features and Trends

The article deals with the current migration situation in the European Union with an emphasis on Austria. The article analyzes the key prerequisites and factors that caused demographic and social changes in Austrian society after World War II, contribute to the preservation of the migration attractiveness of the state at the current stage. The regulatory and legal instruments for regulating migration, including the stay and employment of foreign citizens, as well as the parameters of the functioning of integration mechanisms and ensuring national security against the background of the crisis events of 2015 are summarized. In the context of increasing external pressure on the European Union, Vienna's approaches to managing migration processes are analyzed, which are traditionally characterized by a tough position and often contrast with the official course of Brussels, especially with regard to the reception of refugees. Austrians, in order to prevent irregular cross–border movements of people and secondary migration, minimize threats to national security, actively interact with neighboring states and countries – migration donors. On the domestic political track, of particular interest is the situation associated with a new phenomenon – the mass arrival of Ukrainian refugees. This flow is qualitatively and quantitatively significantly different from traditional migration (gender, educational and social level, significant number of minors). Despite the rigidity of its migration policy, Austria is forced to quickly look for solutions to a complex of problems related to the accommodation and financing of the stay of immigrants from Ukraine, as well as to explain to its electorate the reasons for negative socio-economic changes in the conditions of the chosen foreign policy course. A side effect of providing broad social and legal guarantees to Ukrainians, along with a low level of integration into society, is the growing discontent of the titular population and migrants who arrived from other countries.

Coordinating settlement (im)mobilities: exploring secondary migration patterns and settlement geographies among refugee-humanitarian migrants in regional Australia

ABSTRACT International migrants play an important role in addressing the social and economic challenges associated with population ageing and fertility decline that are keenly felt in regional Australia. In a policy arena where the attraction and retention of migrants remains a challenge, large numbers of refugee-humanitarian migrants have, without any direct government policy intervention, independently gravitated towards unplanned regional settlement locations. However, these secondary migration patterns, often regarded as ‘organic’ or informal, are not well understood. We present new insights into their mobility in regional Australia using secondary datasets and primary research. Using Institutional Ethnographic methods, we highlight how their movements are not as ‘organic’ as imagined. Simultaneously, through the 'new mobilities' paradigm, we highlight the link between international and internal migration of refugee-humanitarian migrants. We tease out the relational element by drawing attention to how immobility of family members, structured by immigration policies that delay and deny family reunification, is intertwined with secondary migration patterns in Australia. As regional communities embrace the benefits of the secondary migration of refugee-humanitarian migrants, we show that these benefits are perversely supported by punitive family reunification policies that can have implications for the successful integration of refugee-humanitarian migrants.

Refugee Integration Outcomes cohort study: Evidence for policy and planning

Evidence on refugee integration outcomes in the UK is lacking, partly due to an absence of datasets which permit refugees to be identified. The RIO longitudinal cohort study designed in collaboration with the Home Office aims to address this by linking administrative data longitudinally.&#x0D; RIO covers cohorts granted asylum and refugees resettled in England &amp; Wales via the Vulnerable Persons and Vulnerable Children’s resettlement Schemes between 2015 and 2020. Linked data include the Personal Demographics Service from the NHS and Exit Checks from the Home Office. Census 2021 data have also been linked to the study. Deterministic linkage algorithms addressed different naming conventions across a wide set of cultures and administrative data quality. Associative linkage methods were developed to match residuals from the deterministic stage to their corresponding household if present. We conducted our own internal quality analysis to assess the quality of our linkage algorithms to improve our methodology ahead of incorporating new administrative data such as HMRC and DWP data.&#x0D; Experimental analysis has looked at social and economic outcomes for these refugee cohorts. Linkage to NHS data helps us understand access to health services and time taken to access these services once resettled. Census 2021 data provide a rich understanding of integration outcomes up to 6 years after arrival or grant of asylum. We demonstrate the potential of linked census data to provide evidence on housing, education, health, access to the labour market, education, households and secondary migration but also how this varies for asylum and refugee cohorts but also by age, sex and geographical region.&#x0D; RIO is aligned to the ONS strategic objective of inclusivity and recommendations made by the UK National Statistician’s Inclusive Data Task Force. RIO will ultimately help inform local authorities, government, charities and other organisations with resource allocation for these vulnerable populations. We are planning to make this dataset available to Accredited Researchers via the ONS Secure Research Service and the Integrated Data Service (IDS).

Differentiation of the Bazhenov Formation Bitumoids in the North-Surgut Region during Generation and Migration

Abstract —The Bazhenov Formation of the Western Siberian oil-and-gas province is currently one of the key objects of potential growth in oil reserves and production. Here we present results of a geochemical study of the Bazhenov Formation according to the methodology developed at Trofimuk Institute of Petroleum Geology and Geophysics, Novosibirsk (IPGG SB RAS) for rocks highly enriched in organic matter. The features of the group and hydrocarbon compositions of the bitumoids that are filling open and closed pores of the Bazhenov Formation rocks from the North-Surgut region were considered. It has been established that most of the naphthides are in a free (phase-segregated) or sorbed state in a closed pore space. The open pores contain the most mobile components of bitumoids, redistributed from closed pores during the primary migration and remained after the secondary migration of naphtides from the Bazhenov Formation to the Berriasian–lower Aptian reservoirs (A and B strata groups). The methodology used in this work allows determining intervals with increased open porosity and oil saturation in the section of the Bazhenov Formation (silicites and carbonates) by the volume of pore space occupied by open-pore bitumoids.

What Kind of Weapon Is Education? Teleological Violence, Local Integration, and Refugee Education in Northern Ethiopia

Abstract Why does education damage refugees? To understand this, we need to ask how education frames refugees’ thinking about their future, specifically related to questions of waiting in the camp or migrating through dangerous, irregular channels. Between 2016 and 2019, Ethiopia was at the forefront of trends in migration policy that prioritized education as part of a global strategy to prevent irregular, northward migration. However, despite increased educational opportunities, refugees rejected schooling as they weighed the decision to migrate onwards, citing a sharp disconnect between aspirations connected to schooling and the constraints on professional and personal progress that they face in hosting states. Drawing on long-term, multi-sited, ethnographic research on temporal violence, and temporal agency among Eritrean refugees in Ethiopia, we develop the concept of teleological violence to describe the harm generated by this disconnect, as risky secondary migration may come to seem like the only path toward a desired future.

Analytical approach for multivariate exploration planning via secondary migration modelling

Identifying potential petroleum traps in petroleum basins is one of the key challenges in petroleum exploration. Specifically, it is the identification of probable petroleum traps within a set of stratigraphic traps of a particular location of source rock and carrier bed. One solution lies in understanding the behaviour of hydrocarbon flow during secondary migration, and the evaluation of the probability of successful transport from the source rock to the trap. Modern reservoir simulators rely on numerical methods to model the oil/gas secondary migration. Using numerical simulators is, however, cumbersome and requires high volumes of data and computation time, which affects successful decision-making in exploration planning. Yet, analytical models are fast and allow for multivariant analysis of hydrocarbon secondary migration requiring only a moderate amount of geological data. This study presents the analytical modelling of hydrocarbon buoyant transport in petroleum basins by including the (i) areal variation of stringers’ cross-section, (ii) chemical reactions including oil biodegradation and (iii) hydrological water flow. The explicit formula is provided for the first and last moments of hydrocarbon arrival at the trap, describing the dynamics of filling of the trap. Field data from Australian and Chinese basins are used to investigate the effects of the above-mentioned parameters on the first and last moments of hydrocarbon arrival at the trap.

Oil–Source Correlation and Secondary Migration Paths in the Triassic Chang 10 of the Yanchang Formation in the Zhidan Area, Ordos Basin, China: Evidence from Biomarkers, Rare Earth Elements, and Carbazole Signatures

Oil–Source Correlation and Secondary Migration Paths in the Triassic Chang 10 of the Yanchang Formation in the Zhidan Area, Ordos Basin, China: Evidence from Biomarkers, Rare Earth Elements, and Carbazole Signatures