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Assessment of Radiological Hazards of sedimentary, Igneous and Sediments Natural Rocks

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World Journal of Nuclear Science and Technology 2024年第2期14卷 131-145页

作者： Wafaa Arafa Hala Mahmoud Eman Yousf Ashry Ashry Ibrahim Elaassy Ahmed Elsersy Faculty of Women Ain Shams University Cairo Egypt Nuclear Material Authority Cairo Egypt Faculty of Education Ain Shams University Cairo Egypt National Institute of Standard Giza Egypt

Gamma-ray spectroscopy based on a 100% efficiency hyper-pure germanium detector was used to evaluate the activity concentrations of 226Ra, 232Th, and 40K natural radionuclides in sedimentary, conglomerate, igneous and sedi-ments rock samples collected from four different locations in Eastern desert in Egypt. The obtained activity concentrations are used to evaluate the radi-ological hazards indices, absorbed dose rate, annual effective dose equivalent in air, radium equivalent, external and internal hazard index, radiation level index, annual gonadal dose equivalent, excess lifetime cancer risk and expo-sure rate. The results show that 1) the absorbed dose rate depends on the rock type, 2) the annual effective dose equivalent in air in 71% of sample below 20 mSvy-1 (permissible limit for workers), 3) the conglomerate rocks show low radioactivity level, 4) sedimentary rocks are rich in radium while igneous rocks are rich in thorium and the sediments rocks are rich in both radium and thorium.

关键词： Gamma Spectrometry Radiological Hazard Indices NORM sedimentary Conglomerate Igneous Sediments

Quaternary integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science China Earth Sciences 2024年第4期67卷 1360-1394页

作者： Yong WANG Mianping ZHENG Yuan LING Shuyuan XIANG Zhaogang SHAO Kexin ZHANG Xue KE Xiao LIN Fang HAN Jian’en HAN Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Institute of Mineral Resources Chinese Academy of Geological SciencesBeijing 100037China Faculty of Earth Sciences China University of GeosciencesWuhan 430074China Chinese Academy of Geological Sciences Beijing 100037China Institute of Geological Survey China University of GeosciencesWuhan 430074China School of Earth Sciences East China University of TechnologyNanchang 330013China Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China

The Quaternary strata on the Qinghai-Tibet Plateau contain rich information about the paleoclimate and environmental evolution,record the evolution process of the Quaternary regional tectonics,paleogeography,and geomorphology of the plateau,and are extremely important areas for studying the Quaternary geological events and regional environmental evolution.According to a comprehensive analysis of the regional stratigraphic data and the development and evolution characteristics of the biota,based on the differences in the lithostratigraphic units,sedimentary characteristics,landforms,and drainage systems,the Quaternary strata on the Qinghai-Tibet Plateau and its surrounding areas are divided into five stratigraphic regions:the Tarim region,Loess Plateau region,Qinghai-Tibet Plateau region,Yunnan-Guizhou Plateau region,and India-Ganges region.The Qinghai-Tibet Plateau stratigraphic region is divided into seven stratigraphic sub-regions:the West Kunlun-Karakorum,AltunQilian Mountains,Qaidam-Hehuang,East Kunlun-Bayan Har,Qiangtang,East Xizang-West Yunnan-West Sichuan,and Gangdise-Himalayan sub-regions.This paper briefly describes the lithostratigraphic units of the seven stratigraphic sub-regions of the Qinghai-Tibet Plateau.According to the lithostratigraphic sequence and its sedimentary characteristics,stratigraphic contact relationship,formation age,and evolution of the biota in each stratigraphic sub-region,the Quaternary tectonic paleogeographic evolution of the Qinghai-Tibet Plateau is divided into four stages.(1)The inherited differential uplift stage since the Pliocene(2.6-1.8/1.5 Ma):the regional sedimentary differences were significant,and the stratigraphic distribution was limited,the alluvial-proluvial sandy conglomerate was widely developed along the piedmont,and fluvial and lacustrine deposits were developed in the low-lying areas between the mountains.(2)The mountain range flattening stage(1.8/1.5-1.2/0.8 Ma):the erosion unconformity surfaces around the plateau were widely distributed,large rivers were

关键词： Quaternary stratigraphic sedimentary

sedimentary facies and depositional model of shallow water delta dominated by fluvial for Chang 8 oil-bearing group of Yanchang Formation in southwestern Ordos Basin,China

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Journal of Central South University 2015年第12期22卷 4749-4763页

作者：陈林陆永潮吴吉元邢凤存刘璐马义权饶丹彭丽 Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education (China University of Geosciences (Wuhan)) Faculty of Earth Resources China University of Geosciences (Wuhan) Exploration and Development Institute Huabei Branch Company of SINOPEC Institute of sedimentary Geology Chengdu University of Technology

A systematic analysis of southwestern Ordos Basin's sedimentary characteristics,internal architectural element association styles and depositional model was illustrated through core statistics,well logging data and outcrop observations in Chang 8 oil-bearing group.This analysis indicates that shallow water delta sediments dominated by a fluvial system is the primary sedimentary system of the Chang 8 oil-bearing group of the Yanchang Formation in southwestern Ordos Basin.Four microfacies with fine grain sizes are identified: distributary channels,sheet sandstone,mouth bar and interdistributary fines.According to the sandbody's spatial distribution and internal architecture,two types of sandbody architectural element associations are identified: amalgamated distributary channels and thin-layer lobate sandstone.In this sedimentary system,net-like distributary channels at the delta with a narrow ribbon shape compose the skeleton of the sandbody that extends further into the delta front and shades into contiguous lobate distribution sheet sandstone in the distal delta front.The mouth bar is largely absent in this system.By analyzing the palaeogeomorphology,the palaeostructure background,sedimentary characteristics,sedimentary facies types and spatial distribution of sedimentary facies during the Chang 8 period,a distinctive depositional model of the Chang 8 shallow water fluvial-dominated delta was established,which primarily consists of straight multi-phase amalgamated distributary channels in the delta plain,net-like distributary channels frequently diverting and converging in the proximal delta front,sheet sandstones with dispersing contiguous lobate shapes in the distal delta front,and prodelta or shallow lake mudstones.

关键词： sedimentary facies architectural element depositional model shallow water delta Chang 8 oil-bearing group Ordos Basin

sedimentary geochemistry of the Cambrian-Ordovician cherts: Implication on archipelagic ocean of North Qilian orogenic belt

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Science China Earth Sciences 2007年第11期50卷 1628-1644页

作者： DU YuanSheng1,2, ZHU Jie1, GU SongZhu1, 2, XU YaJun1 & YANG JiangHai1 1 Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074, China 2 Key Laboratory of Biogeology and Environment Geology of Education Ministry, Wuhan 430074, China Faculty of Earth Sciences China University of Geosciences Wuhan China Key Laboratory of Biogeology and Environment Geology of Education Ministry Wuhan China

The Caledonian North Qilian orogenic belt lies between the North China plate and the Qaidam mi-croplates, and resulted from the collision among the Qaidam microplate, mid-Qilian block and the North China plate. The orogen initiated from the rifting of the Late Proterozoic Rodinia, and then it experi-enced stages of Cambrian rift basin and Ordovician archipelagic oceanic basin, and foreland basin during Silurian to Early-Middle Devonian. The average ratios of Al/(Al+Fe+Mn), Al/(Al+Fe), δ Ce, Lan/Ybn and Lan/Cen from cherts of Cambrian Heicigou Formation are 0.797, 0.627, 1.114, 0.994 and 1.034 re-spectively. In the NAS standardized REE distribution pattern, the cherts from Xiangqianshan is slightly HREE enriched, and the cherts from Ganluci and Shiqingdong are plane. All of these features indicated that Cambrian cherts of the Heicigou Formation originated from a continental margin rift background. On the contrary, the average ratios of Al/(Al+Fe+Mn), Al/(Al+Fe), δ Ce, Lan/Ybn, Lan/Cen of the Ordovician chert from Dakecha, Cuijiadun, Shihuigou, Laohushan, Heicigou, Maomaoshan, Bianmagou, Da-chadaban, Baiquanmen, Jiugequan and Angzanggou, are respectively 0.72, 0.58, 0.99, 1.09 and 0.96 respectively. Their NAS standardized REE distribution patterns of most Ordovician cherts are plane mode or slightly HREE enriched. The REE distribution pattern of few samples of cherts are slightly LREE enriched. Characteristics of sedimentary geochemistry and tectonic evolution demonstrated that the Cambrian-Ordovician cherts, associated with rift, oceanic, island arc and back-arc volcanic rocks, was not formed in a typical abyssal oceanic basin or mid-oceanic ridge. On the contrary, they formed in a deepwater basin of continental margin or a archipelagic ocean tectonic setting. Several Early Paleo-zoic ophiolite belts in North Qilian and adjacent periphery Qaidam microplate imply that an archipelagic ocean during Ordovician existed in the east of Pro-Tethys.

关键词： North Qilian orogenic belt,Cambrian-Ordovician,cherts sedimentary geochemistry,archipelagic ocean

sedimentary characteristics comparison and genesis analysis of the deepwater channel in the hydrate enrichment zones on the north slope of the South China Sea

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Acta Oceanologica Sinica 2019年第3期38卷 103-113页

作者： Chao Fu Xinghe Yu Yiis Dong Yulin He Jinqiang Liang Zenggui Kuang School of Energy Resources China University of Geosciences Institute of Geology and Geophysics Chinese Academy of Sciences Guangzhou Marine Geological Survey Ministry of Land and Nature Resource

Natural gas hydrate(NGH) is one of the important clean energy at present and even in the future. The study of its sedimentary environment and minerogenetic condition has long been a hot issue that has received much concern from geologists all over the world. China has successfully obtained the samples of NGH in Shenhu and Dongsha sea areas in 2007, 2013 and 2015, respectively. From this, the continental slope north of the South China Sea becomes an important test site for the study of NGH sedimentary genesis and minerogenetic condition. NGH has been found in Shenhu, Dongsha and Qiongdongnan areas within the continental slope north of South China Sea,at different depths of water, with different sedimentary characteristics, gas genesis, and minerogenetic conditions.Using a seismic sedimentology theory, combining seismic facies results of each facies, sedimentary facies and evolution of each area are documented in turn establishing a sedimentary model by considering palaeogeomorphology, sea level change and tectonic movement. The channel system and MTD(Mass Transport Deposition) system among these three areas were compared focusing on the developing position, appearance and controlling factors. Relative location among three areas is firstly defined that Dongsha area in a nearprovenance steep upper slope, Shenhu area in a normal gentle slope and Qiongdongnan area in an awayprovenance flat plain. Besides, their channel systems are classified into erosional, erosional-aggradational and aggradational channel, and MTD systems into headwall domain, translational domain and toe domain.

关键词： sedimentary characteristics deep-sea channel genesis comparison hydrate enrichment zones

sedimentary geochemistry and provenance of the Lower and Middle Devonian Laojunshan Formation,the North Qilian Orogenic Belt

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Science China Earth Sciences 2010年第3期53卷 356-367页

作者： XU YaJun DU YuanSheng YANG JiangHai HUANG Hu Key Laboratory of Biogeology and Environmental Geology of China Education Ministry China University of GeosciencesWuhan 430074China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China

The Laojunshan Formation is a suite of molasse formed during the rapid uplift of the North Qilian Orogenic Belt (NQOB). Forty-one samples of sandstone have been collected from the Sunan and Minle sections in the western sector and the Gulang and Jingyuan sections in the eastern sector of the NQOB belt. Geochemical analyses of those samples indicated: 1) The MgO+Fe2O3T and Al2O3/SiO2 values are higher, and K2O/Na2O ratios are lower in the western sector than those in the eastern sector. 2) All of them are depleted in Nb and Ta elements. The samples from the western sector are depleted in Rb element and enriched with Sc, Co, Ni, V, and Cr elements in the Upper Crust-normalized patterns. However, those from the eastern sector are depleted in Sr without enrichments of Sc, Co, Ni, V, and Cr. 3) All of the samples display a right-inclined REE pattern af- ter Chondrite-normalized REE pattern. But LaN/YbN and Eu/Eu* ratios of the samples from the western sector are lower than those of the samples from the eastern sector. These geochemical characteristics suggest the prominent input of mafic clast with minor granitic rocks into the Sunan area, felsic clast into the Gulang and Jingyuan area, and both mafic and felsic clast into the Minle area. The angular shapes of gravels imply that these ill-sorted sediments were deposited near their sources without recy- cling. Geochemical features above also demonstrated that no major chemical weathering occurred for the western provenance, but deposits in the eastern sector resulted from low or middle degree chemical weathering. Evidences combining tectonic discriminations and comparisons with potential provenances revealed that sediments in the Sunan area were derived mainly from the North Qilian Continental arc, whereas sediments in the Minle, Gulang, and Jingyuan areas were derived not only from the North Qilian Continental arc but also from the basement of the Middle Qilian block. Integrated with the characteristics of development of Silurian and Devonian, these imply that the oro

关键词： North Qilian Orogenic Belt (NQOB) Laojunshan Formation sedimentary geochemistry provenance orogeny

sedimentary and geochemical characteristics of the Triassic Chang 7 Member shale in the Southeastern Ordos Basin,Central China

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Petroleum Science 2019年第2期16卷 285-297页

作者： Jing-Wei Cui Ru-Kai Zhu Zhong Luo Sen Li Research Institute of Petroleum Exploration and Development PetroChina Shandong Provincial Key Laboratory of Depositional Mineralization and sedimentary Minerals Shandong University of Science and Technology

The Ordos Basin is the largest petroliferous basin in China, where the Chang 7 Member shale serves as the major source rock in the basin, with an area of more than 100,000 km^2 So far, sedimentary and geochemical characterizations have rarely been conducted on the shale in shallow(sedimentary and geochemical characterizations were conducted for the well-outcropped YSC section. The study results show that the Chang7 Member shale is widely distributed laterally with variable thickness. The organic-rich shale is 7-25 m thick in total and exhibits obvious horizontal variation in mineral composition. In the eastern sections, the shale contains organic matter of TypeⅡ_2-Ⅲ and is low in thermal maturity, with high clay mineral content, low K-feldspar content, and no pyrite. In the western sections, the shale contains Type Ⅱ_1 organic matter and is low in thermal maturity, with high clay mineral, K-feldspar, and pyrite contents. The YSC section reveals three obvious intervals in vertical mineral composition and organic abundance.The Chang 7 Member organic-rich shale(TOC > 10%) contains mainly sapropelite and liptinite, with Type Ⅱ kerogen. It is generally characterized by a hydrocarbon potential of more than 70 mg/g, low maturity, and shallow-semideep lacustrine facies. In the western sections, the shale, still in a low maturity stage, has a higher hydrocarbon potential and is optional for shale oil recovery. However, the Chang 7 Member shale in the study area is highly heterogeneous and its shale oil recovery is practical only in the organic-rich intervals.

关键词： Ordos Basin Chang 7 Member oil Organic-rich shale sedimentary characteristics Geochemical characteristics

sedimentary environment indicators: Benzothiazole and its derivatives

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Chinese Science Bulletin 2001年第5期46卷 412-416页

作者： LI Yuan LI Renwei ZHOU Shixin LUO Binjie Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China Lanzhou Institute of Geology Chinese Academy of SciencesLanzhou 730000China

Benzothiazoles distributional characteristics of crude oils and non-hydrocarbon fractions of source rocks in Mangya depression of the Qaidam Basin, Lunnan oil field in the Tarim Basin, Kelamayi oil field in the Junggar Basin and the Tulufan Basin oil field were analyzed. It was found that the distributions of benzothiazole are remarkable diversity in different sedimentary environmental oils. The swamp crude oils contain high quantity of benzothiazole and relatively high quantity of alkylthio-benzothiazole and 2(3H)-benzothiazolone. But the quantity of the 2,2’-dithiobis-benzothiazole is relatively low. The abundance of benzothiazole and 2,2’-dithiobis-benzothiazole are relatively high insemi-brackish water lacustrine crude oils, but the quantity of alkylthio-benzothiazole and 2(3H)-benzothiazolone are relatively low. The benzothiazoles belong to weak acid and mild base compound, and their stabilization conditions relate to their environmental medium. The nitrogenous bases are in favor of alkalescence

关键词： crude oils source rock non-hydrocarbon fraction benzothiazoles sedimentary environment.

General regulations about submitting manuscripts to Journal of Palaeogeography

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Journal of Palaeogeography 2024年第1期13卷 F0003-F0003页

1.Journal of Palaeogeography [JoP] publishes in the general fields of sedimentology and palaeontology that include a distinct and noticeable palaeogeographic aspect or perspective.High-quality original research articles and authoritative reviews are welcomed.Subdisciplines of interest to JoP include (but not limited to):Facies analysis and sedimentary environments;Palaeobiology (including taxonomy) and palaeoecology;Palaeobiogeography;Stratigraphy;Sequence stratigraphy;sedimentary geochemistry;Provenance analysis;Palaeoclimatology.

关键词： geochemistry sedimentary environments