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Fluorene (FL), dibenzothiophene (DBT) and dibenzofuran (DBF) and their alkylated homologues are important polycyclic aromatic compounds in crude oils and source rock extracts. They share the similar chemical structure and may have genetic relationships. The parent compounds (unsubstituted), methyl-, dimethyl- and ethyl-substituted isomers are identified by comparison with retention indices reported in literatures and correlation with co-injection of internal standards in gas chromatography-mass spectrometry (GC-MS) analysis. Therefore, their relative concentrations can be determined. Based on the large data sets, this paper preliminarily establishes a ternary diagram to interpret the depositional environment/lithology for oils and related source rocks. Five typical depositional environments/lithologies are distinguished on this ternary diagram. Data points from typical marine carbonate, fluvial/deltaic/fresh lacustrine shale and swamp fall into the DBTs, FLs and DBFs end-members, respectively. Oils from marine shale have subequal contents of FLs and DBFs and lie between the zones of fluvial/deltaic/fresh lacustrine shale and swamp, but have a little higher abundance of DBTs. The oils from brackish/saline lacustrine have intermediate contents of DBTs with a wide variety and some degree overlap with that of marine shale. On the basis of the ternary diagrams, two petroleum systems in the cratonic region of the Tarim basis are defined. The majority of discovered oils were derived from the Middle-Upper Ordovician carbonate source rocks. Whereas, some oils from wells TD2, T904, LK1 and TZ62 originated from the Cambrian and Lower Ordovician source rocks. Therefore, the ternary diagram of FLs, DBTs and DBFs is a useful method to interpret depositional environment/lithology for oils and related source rocks and to definite petroleum systems as well.

A sedimentological investigation of the Neogene deposits of the Zagros foreland basin in SW Iran reveals a continuous and largely gradational passage from supratidal and sabkha sediments at the base (represented by the Gachsaran Formation) to carbonates and marine marls (Mishan Formation with basal Guri carbonate member) followed by coastal plain and meandering river deposits (Agha Jari Formation) and finally to braided river gravel sheets (Bakhtyari Formation). This vertical succession is interpreted to represent the southward migration of foreland basin depozones (from distal foredeep and foredeep to distal wedge-top and proximal wedge-top, respectively) as the Zagros fold–thrust belt migrated progressively southward towards the Arabian foreland. This vertical succession bears a striking similarity to modern depositional environments and sedimentary deposits observed in the Zagros region today, where one passes from mainly braided rivers in the Zagros Mountains to meandering rivers close to the coast, to shallow marine clastic sediments along the northern part of the Persian Gulf and finally to carbonate ramp and sabkha deposits along the southeastern coast of the Persian Gulf. This link between the Neogene succession and the modern-day depositional environments strongly suggests that the major Neogene formations of the Zagros foreland basin are strongly diachronous (as shown recently by others) and have active modern-day equivalents.

In Timpoweap Canyon near Hurricane (Utah, USA), spectacular outcrop conditions of Early Triassic rocks document the geometric relationships between a massive Smithian fenestral-microbial unit and underlying, lateral and overlying sedimentary units. This allows us to reconstruct the evolution of depositional environments and high-frequency relative sea-level fluctuations in the studied area. Depositional environments evolved from a coastal plain with continental deposits to peritidal settings with fenestral-microbial limestones, which are overlain by intertidal to shallow subtidal marine bioclastic limestones. This transgressive trend of a large-scale depositional sequence marks a long-term sea-level rise that is identified worldwide after the Permian–Triassic boundary. The fenestral-microbial sediments were deposited at the transition between continental settings (with terrigenous deposits) and shallow subtidal marine environments (with bioturbated and bioclastic limestones). Such a lateral zonation questions the interpretation of microbial deposits as anachronistic and disaster facies in the western USA basin. The depositional setting may have triggered the distribution of microbial deposits and contemporaneous marine biota. The fenestral-microbial unit is truncated by an erosional surface reflecting a drop in relative sea level at the scale of a medium depositional sequence. The local inherited topography allowed the recording of small-scale sequences characterized by clinoforms and short-distance lateral facies changes. Stratal stacking pattern and surface geometries allow the reconstruction of relative sea-level fluctuations and tracking of shoreline migrations. The stacking pattern of these small-scale sequences and the amplitude of corresponding high-frequency sea-level fluctuations are consistent with climatic control. Large- and medium-scale sequences suggest a regional tectonic control.

Hanamgond, P.T., 2024. Morpho-dynamics of Malvan-Devbag Beach, Maharashtra, West Coast of India. In: Phillips, M.R.; Al-Naemi, S., and Duarte, C.M. (eds.), Coastlines under Global Change: Proceedings from the International Coastal Symposium (ICS) 2024 (Doha, Qatar). Journal of Coastal Research, Special Issue No. 113, pp. 240-245. Charlotte (North Carolina), ISSN 0749-0208. The coastal length of Maharashtra is about 720 Kms which is almost 10% of the Indian coast. The beaches here are micro-tidal (0-2 m tidal range) with semi diurnal tides. The present study area- the Malvan-Devbag beach stretching about 15km, is a barrier beach along the south Konkan coast region of Maharashtra state. The coastal region here is hilly, narrow highly dissected with transverse ridges of the Western Ghats, and at many places extending as promontories into Arabian Sea. The shoreline is very irregular, associated with features like cliffs, notches, promontories, sea caves, embayments, submerged shoals and offshore islands. The morpho-dynamics at 7 locations, on monthly, seasonal and annual scale during June 2008 to July 2010 indicated dominating erosion during May/June (approach of monsoon) and reach the peak during monsoon (July/August). The beach starts regaining during September and develops fully by May with well-developed berm(s). The algebraic sum of volume change showed overall gain. It is observed that the longshore currents (both northerly and southerly) occur in the range of 0.2 - 1.0 m/sec; and majority of the currents are in the range of 0.2-0.4 at all the locations with the predominance of northerly currents. Sediment samples were collected across all the locations at 10m interval. The sediment size varies between medium to very fine, majority being fine, well sorted to moderately sorted. In general, the sediments of the study area are deposited under moderate to high-energy turbulence conditions. The CM patterns indicate moderate to high energy conditions of deposition. The sediment movement paths differ between station to station. In general, the alongshore sediment paths show northerly sediment transport during all the seasons. The cross-shore sediment movement shows cyclic behavior i.e., during monsoon it shows offshore transport and during fair-weather it shows onshore transport. This corroborates the general trend of West Coast beaches and supports the growth of the beach during the fair-weather season.

The Bir Dakhl section which is located in the southern Galala plateau, north eastern desert was sampled for microfacies analysis of the upper Cretaceous-lower Paleogene succession. Microfacies analysis led to the recognition of eight mixed clastic-carbonate facies types (black shale lithofacies MF-1, pure shale lithofacies MF-2, sandy shale lithofacies MF-3, marly shale lithofacies MF-4, mudstone microfacies MF-5, foraminiferal wackestone microfacies MF-6, bioclastic wackestone microfacies MF-7, and bioclastic packstone microfacies MF-8) of the studied interval. These microfacies can be grouped into three depositional environments: inner, middle and outer ramp. The interpreted depositional environments have been suggested to range from neritic to middle bathyal (∼ 700 m). Based on cyclostratigraphy, five deepening upward cycles and three shallowing upward cycles have been differentiated in Bir Dakhl section. Copyright 2016 Geological Society of India

Granulometrical, mineralogical and morphological investigation of the sea-bottom sediments in the Grgur Channel revealed five sediment types; the most frequent of them are muds containing some amount of coarse sediment fractions (sand and gravel). The coarsest fractions are prevalently composed of recent shell fragments. Unexpected well rounded carbonate gravel was found SE of the Prvić Island at 83 m of water depth. This gravel was presumably transported, shaped and deposited during a lowstanding sea-level by stream and/or in beach environment. Fine-grained fractions have siliciclastic composition and show a prevalenty terrigenous origin. One part of the fine-grained fraction originates from recent subaerial weathering of flysch outcrops and the other from subaerial erosion of presently submerged flysch outcrops active during a lower sea-level. Due to the rapid Late Pleistocene-Holocene transgression, the investigated sediments are now below the present wave-base. Due to the presumed very low or even negligible recent sedimentation in the study area, older sediments in the Grgur Channel remain uncovered and mixed by burrowing organisms. Therefore, analyzed surface sediments from the Grgur Channel are considered as a mixture of recent and subrecent deposits. By this investigation, a new seabed sediments map of the Grgur Channel was produced, as an improvement of the existing sedimentological map of the Kvarner area.

The present study aims to investigate petrography characteristics and sedimental environments of upper Olenekian—middle Anisian deposits of Nakhlak group in the sedimentary-structural zone of central Iran. To this end, a section of these deposits with a thickness of 720 meters was first selected, and 190 samples were taken from this section for preparing thin sections. Also, quantitative and qualitative laboratory tests were performed and 25 samples of sandstone were selected for point counter analysis. The results indicated that the major deposits of this formation are related to siliciclastic, carbonate, and pyroclastic types, which are in the form of two facies associations. The facies association A at the bottom of the studied section with the thickness of 90 meters has a periodicity of clastic, carbonate, and pyroclastic facies. The clastic facies of this association consists of fine-grained sandstone. In addition, the carbonate facies in association A are characterized by two microfacies consisting of intraclast oolitic grainstone and oolitic grainstone. Further, tuffite is the only pyroclastic facies related to association A, which has a laminate structure, cross-bedding lamination, herringbone bedding, and upward-thinning and thickening cycles. The facies association, B which is deposited later, is more in the middle and top part of the section. The facies association B is 660 meters thick and has a periodicity of clastic and limestone facies. Clastic facies of this association includes four lithofacies such as conglomerate, pebble coarsegrained sandstone, medium-grained sandstone to thin layer siltstone and shale. The carbonate facies consists of four microfacies such as sandy intraclastic wackestone and mudstone. Furthermore, slumping structures, cross bedding, turbulence, boudinage structure, and convolute of sediments, along with the effects of erosional channels are observed in facies B. Field and laboratory studies conducted on this succession indicate the structure of facies association A was deposited in a mixed siliciclastic carbonate ramp. Finally, submarine canyons and submarine fan environments were left by increasing the depth of the facies association B in the deep part of sea and turbidity systems. El objetivo del presente estudio está dirigido a la investigación de las características petrográficas y los ambientes sedimentarios de los depósitos antiguos de los Olenekianos Anisianos Medio, hecho por el grupo Nakhlak, en la zona sedimentaria-estructural del centro de Irán. Con este fin, se seleccionó una parte de estos depósitos con un espesor de 720 metros y después se tomaron 190 muestras de esta parte para preparar secciones finas. También, se realizaron pruebas de laboratorio cuantitativas y cualitativas y se seleccionaron 25 muestras de arenisca para el análisis de contadores de puntos. Los resultados indicaron que los principales depósitos de esta formación están relacionados con tipos siliciclásticos, carbonatados y piroclásticos, que son en forma de dos asociaciones facies. La asociación de facies de “A” al principio de la parte estudiada con el espesor de 90 metros, tiene una periodicidad de facies clásicas, carbonatadas y piroclásticas. Las facies clásicas de esta asociación consisten en arenisca de grano fino. Además, las facies carbonatadas en la asociación “A” se caracterizan por dos micro facies que consisten en piedra granulada intra oolítica y piedra granulada oolítica. Además, la toba es la única facies piroclásticas relacionadas con la asociación “A”, que tiene una estructura laminada, laminación cruzada, lecho de espiga y ciclos de adelgazamiento y engrosamiento ascendentes. La asociación de facies “B”, que se deposita más tarde, se observa más en la parte media y final de la sección examinada por este estudio. La asociación facies de “B” es de 660 metros de largo y tiene una periodicidad de facies clásicas y calizas. Las facies clásicas de esta asociación incluyen cuatro litófagas tales como conglomerado, piedra arenisca de grano grueso, arenisca de grano medio a fina capa de limolita y esquisto. Las facies de carbonato se componen de cuatro micro facies como wackestone, intraclástico, arenoso y mudstone. Además, en la facies “B” se observaron estructuras empinadas, lecho cruzado, turbulencia, estructura de boudinage y complejidad de los sedimentos junto con los efectos de los canales de erosión. Los estudios de campo y de laboratorio realizados sobre esta sucesión indicaron la estructura del depósito de asociación de facies “A” en una rampa de carbonato siliciclástico mixto. Por último, los cañones submarinos y los entornos de los ventiladores submarinos se dejan al aumentar la profundidad de la asociación facies B en la parte profunda del mar y los sistemas de turbidez.

.Khon Kaen’s petrified wood fossil sites in northeastern Thailand, though less studied, hold significant paleontological value. These sites offer crucial insights into the region’s geology. The Quaternary gravel beds, which contain a diverse array of petrified wood, were deposited on elevated terraces along the western boundary of the Khon Kaen subbasin. Field investigations focused on collecting sedimentological data to analyze the stratigraphic sequence, identify lithofacies, and characterize architectural elements in the gravel pits. The unconsolidated units (Units I–IV) unconformably overlie the Khorat Group bedrock in the Ban Non Rang area (north) and the Ban Kean Phra Doo area (south). From bottom to top, these units are as follows: I) conglomeratic sand, II) lenticular gravel with sand, III) massive gravel, and IV) red sandy soil containing minor pebble clasts. The depositional environment is interpreted as a braided stream on an alluvial fan with some debris flow occurrences, influenced by medium- to high-energy gravity/debris flows (Units I–III). Unit IV is identified as having been influenced by bioturbation processes. The majority of clasts in Units II and III consist of quartz, likely originating from the mountain ranges to the north to northwest of the subbasin.

Coal, being one of the major energy sources for power generation, contains several critical trace elements. There is a growing scarcity and expense of these critical elements as a result of the increased demand and limitation of mining sources. To explore the geochemical characteristics of the rare-metal, rare-dispersed (scattered), and rare-earth elements (TREs) in coal, 25 coal seam samples of the Shanxi Formation in the Huainan coalfield were collected. The major element oxides, minerals, and TREs were analyzed by X-ray fluorescence spectroscopy (XRF), X-ray diffraction (XRD), and inductively coupled plasma-mass spectrometry (ICP-MS). The results revealed that the coal of the Shanxi Formation had ultra-low moisture and low ash yield and was medium–high-volatility with low sulfur content and high calorific value. Concerning minerals, the coal was mainly composed of kaolinite, illite, quartz, calcite, dolomite, and pyrite. Compared with Chinese coal and world hard coal, rare-metal element Li and rare-dispersed element Se were enriched, whereas Ga and Ta were only slightly enriched. The average content of REYs was 51.34 μg/g, which is lower than the average content of REYs in Chinese coal. It has the enrichment characteristics of light REYs. In the vertical direction, the content of most TREs was higher in the roof and floor of the coal seam and the parting, indicating that the sedimentary microenvironment plays an important role in controlling the migration and enrichment of elements. The experimental results of sequential chemical extraction and correlation analysis showed that the TREs in the Shanxi Formation coal mainly exist in a residual and carbonate bound state, and occur in clay minerals and carbonate minerals. The enrichment of Se may be due to its high organic form ratio. The C-value, B content, w(Sr)/w(Ba), and REY geochemical parameters indicated that the Shanxi Formation Coal seam was developed in a transitional, semi-saline, deltaic sedimentary environment. With their development affected by seawater, REYs in coal are greatly supplied by terrigenous clastics. The complex sedimentary environment is an important reason for the varying occurrence states of TREs in the Shanxi Formation coals.

An integrated geological and geophysical approach is presented for the recognition of unconventional targets in the Miocene formations of the Carpathian Foredeep, southern Poland. The subject of the analysis is an unconventional reservoir built of interlayered packets of sandstone, mudstone and claystone, called a “heterogeneous sequence”. This type of sequence acts as both a reservoir and as source rock for hydrocarbons and it consists of layers of insignificant thickness, below the resolution of seismic data. The interpretation of such a sequence has rarely been based on seismic stratigraphy analysis; however, such an approach is proposed here. The subject of interpretation is high-quality seismic data of high resolution that enable detailed depositional analysis. The reconstruction of the depositional history was possible due to the analysis of flattened chronostratigraphic horizons (Wheeler diagram). The identification of depositional positions in a sedimentary basin was the first step for the indication of potential target areas. These areas were also subject to seismic attribute analysis (sweetness) and spectral decomposition. The seismic attribute results positively verified the previously proposed prospects. The results obtained demonstrate that the interpretation of the Miocene sediments in the Carpathian Foredeep should take into account the depositional history reconstruction and paleogeographical analysis.