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Investigating low dispersion isotope dissolution Lu-Hf garnet dates via in situ Lu-Hf geochronology,Kanchenjunga Himal

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Geoscience Frontiers 2024年第3期15卷 137-145页

作者： Kyle P.larson John M.Cottle Mark Button Brendan Dyck Iva Lihter Sudip Shrestha Department of Earth Environmental and Geographic SciencesUniversity of British ColumbiaOkanaganKelownaCanada Department of Earth Science University of CaliforniaSanta BarbaraUSA Fipke Laboratory for Trace Element Research University of British ColumbiaOkanaganKelownaCanada

Re-examination of three specimens from the Kanchenjunga Himal of Nepal via in situ Lu-Hf garnet geochronology yields evidence of multiple garnet growth *** analyses from grain cores in two specimens define Paleozoic regressions whereas analyses from grain rims in the same specimens define low-precision regressions consistent with the timing of Himalayan *** dates contrast with previously published low dispersion,ca.290 Ma isotope dissolution(ID)Lu-Hf garnet dates for the same *** of Lu and spot age distribution in representative grains from the specimens examined yields calculated dates that approximate the Permian-age regressions through the original ID *** findings demonstrate that it is possible to generate low dispersion ID Lu-Hf data from multigenerational garnet with significantly different-age growth events when approximately equal proportions of the different age reservoirs are included in multi-component aliquots.

关键词： Lu-Hf geochronology In situ Lu-Hf geochronology Kanchenjunga Himal

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美国页岩油气地质特征及勘探开发进展

石油勘探与开发 2024年第4期51卷 807-828页

作者： MCMAHON T P larson T E ZHANG T SHUSTER M 美国德克萨斯大学奥斯汀分校杰克逊地质科学学院经济地质局奥斯汀78758-4445德克萨斯州美国

基于美国页岩油气勘探开发历程的回顾,对主要页岩盆地的地质演化、主要页岩层系的油气地质特征及勘探开发进展进行系统梳理和总结。美国重要页岩盆地的富烃页岩主要发育于6个地质时期:中奥陶世、中—晚泥盆世、早石炭世(中—晚密西西比... 详细信息

基于美国页岩油气勘探开发历程的回顾,对主要页岩盆地的地质演化、主要页岩层系的油气地质特征及勘探开发进展进行系统梳理和总结。美国重要页岩盆地的富烃页岩主要发育于6个地质时期:中奥陶世、中—晚泥盆世、早石炭世(中—晚密西西比世)、早二叠世、晚侏罗世和晚白垩世(塞诺曼期—土伦期),构造沉积环境主要包括克拉通内盆地、前陆盆地和被动大陆边缘盆地。古生界富烃页岩主要分布于以下6个盆地:阿巴拉契亚盆地(尤蒂卡页岩和马塞勒斯页岩)、阿纳达科盆地(伍德福德页岩)、威利斯顿盆地(巴肯页岩)、阿卡马盆地(费耶特维尔页岩)、沃思堡盆地(巴内特页岩)和二叠盆地(狼营组和斯帕瑞组/骨泉组页岩)。中生界富烃页岩主要发育在西墨西哥湾盆地(海恩斯维尔组和鹰滩组)和落基山盆地群(以丹佛和粉河盆地的尼尔布拉勒组页岩为主)。通过对各页岩区带的详细分析发现,页岩的岩相和矿物成分存在差异,“页岩储层”并非只是页岩,很多情况下页岩油气还产自粉砂岩和碳酸盐岩等多种岩石类型。美国的页岩油气资源丰富,页岩油地质资源量超过0.246×1012 t,页岩气地质资源量超过290×1012 m3。在开启“页岩革命”的水平井水力压裂技术出现之前,美国经过了长达20年的勘探开发实践和理论技术积累。自2007年至2023年,美国页岩油气产量从约11.2×104t/d油当量增加到超过300.0×104t/d油当量,2017年页岩油气产量超过了常规油气,2023年在油气总产量中的占比增加到60%以上。页岩油气的开发主要得益于钻完井技术的改进,“立体开发”的攻关,以及重复压裂、提高原油采收率和“U”形井等技术的应用。基于美国丰富的页岩资源基础和技术的不断进步,页岩油气的产量将继续为全美的油气生产做出更大贡献。

关键词：美国页岩油页岩气页岩储层非常规储层油气产量资源评价

脂肪组织在CYP1B1基因缺陷小鼠抵抗营养性肥胖中的作用

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脂肪组织在CYP1B1基因缺陷小鼠抵抗营养性肥胖中的作用

Reconsidering the distribution of gray wolves

2008内分泌代谢性疾病系列研讨会暨中青年英文论坛

作者：王素青刘学清 michelle larson Colin R Jefcoate 武汉大学公共卫生学院营养与食品卫生系 Department of Pharmacology and Toxicology University of Wisconsin at Madison 53706

我们实验室发现,CYP1B1参与前脂肪细胞的分化过程,在脂肪形成过程起一定作用。为了更深入研究CYP1B1在脂肪代谢中的作用,我们给予CYP1B1基因敲除小鼠低、高脂膳食,观察其与野生型小鼠的异同及其内在的可能机制。

关键词：

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Zoological Research 2017年第3期38卷 115-116页

作者： Greger larson Palaeogenomics & Bio-Archaeology Research Network Research Laboratory for Archaeology and History of Art University of Oxford UK

When attempting to understand where domestic plants and animals were domesticated, it is essential to consider the geographic distribution of the wild ancestor. Many domestic taxa now inhabit just about every continen... 详细信息

关键词： of have is in were been Reconsidering the distribution of gray wolves

Laboratory investigation of the anisotropic confinement-dependent brittle-ductile transition of a Utah coal

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International Journal of Mining Science and Technology 2021年第1期31卷 51-57页

作者： Bo-Hyun Kim Mark K.larson Mine Safety Branch CDC/NIOSH/SMRDSpokaneWA 99207USA

This paper was developed as part of an effort by the National Institute for Occupational Safety and Health(NIOSH)to identify risk factors associated with bumps in the prevention of fatalities and accidents in highly stressed,bump-prone ground *** of failure mechanism with increasing confinement,from extensional-to shear-dominated failure,are widely observed in the rupture of intact specimens at the laboratory scale and in rock *** the previous analysis conducted in 2018,both unconfined and triaxial compressive tests were conducted to investigate the strength characteristics of some specimens of a Utah coal,including the spalling limits,the ratio of apparent unconfined compressive strength(AUCS)to unconfined compressive strength(UCS),the damage characteristics,and the postyield *** mechanical characteristics were found to be strongly anisotropic as a function of the orientation of the cleats relative to the loading ***,the transition from extensional to shear failure at the given confinements was not clearly *** this study,a total of 20 specimens were additionally prepared from the same coal sample used in the previous study and then tested under both unconfined and triaxial compressive *** different confining stresses are used as analogs for different width-to-height(W/H)ratios of pillar *** the W/H ratios of the specimens were not directly considered during testing,the equivalent W/H ratios of a pillar as a function of the confining stresses were estimated using an existing empirical *** to this relationship,theW/H atwhich in-situ pillar behavior would be expected to transition from brittle to ductile is identified.

关键词： Bump-prone ground conditions A Utah coal Anisotropic Equivalent W/H ratios of a pillar

Development of a fault-rupture environment in 3D: A numerical tool for examining the mechanical impact of a fault on underground excavations

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International Journal of Mining Science and Technology 2019年第1期29卷 105-111页

作者： Bo-Hyun Kim Mark K.larson Spokane Mining Research Division CDC/NIOSH

While faults are commonly simulated as a single planar or non-planar interface for a safety or stability analysis in underground mining excavation, the real 3D structure of a fault is often very complex, with different branches that reactivate at different times. Furthermore, these branches are zones of nonzero thickness where material continuously undergoes damage even during interseismic periods. In this study, the initiation and the initial evolution of a strike-slip fault was modeled using the FLAC3D software program. The initial and boundary conditions are simplified, and mimic the Riedel shear experiment and the constitutive model in the literature. The FLAC3D model successfully replicates and creates the 3D fault zone as a strike-slip type structure in the entire thickness of the model. The strike-slip fault structure and normal displacement result in the formation of valleys in the model. Three panels of a longwall excavation are virtually placed and excavated beneath a main valley. The characteristics of stored and dissipated energy associated with the panel excavations are examined and observed at different stages of shear strain in the fault to evaluate bump potential. Depending on the shear strain in the fault, the energy characteristics adjacent to the longwall panels present different degrees of bump potential, which is not possible to capture by conventional fault simulation using an interface.

关键词： 3D fault zone Strike-slip fault FLAC3D Bump potential Energy characteristics

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韦布望远镜揭密早期宇宙的盛筵

中国国家天文 2024年第6期18卷 40-49页

作者：丹·科丽贝卡·拉森戴昱(译) 空间望远镜科学中心约翰斯·霍普金斯大学罗切斯特理工学院国家天文台

令天文学家欣喜的新望远镜,带来了观测宇宙最初十亿年星系无与伦比的新视角。天文学家在用韦布空间望远镜(James Webb Space Telescope,JWST)观测宇宙最初的几十亿年时,期待看到什么呢?哈勃望远镜的观测已经揭示了宇宙在不同的时期都拥... 详细信息

令天文学家欣喜的新望远镜,带来了观测宇宙最初十亿年星系无与伦比的新视角。天文学家在用韦布空间望远镜(James Webb Space Telescope,JWST)观测宇宙最初的几十亿年时,期待看到什么呢?哈勃望远镜的观测已经揭示了宇宙在不同的时期都拥有多姿多彩的星系。数十亿年前,星系是年轻、活跃,而且无序的——正等待着演化至我们现在看到的壮观的旋臂盘星系和椭圆星系。

关键词：哈勃望远镜椭圆星系盘星系旋臂空间望远镜早期宇宙韦布

Navigating the genomic instability mine field of osteosarcoma to better understand implications of non-coding RNAs

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BIOCELL 2022年第10期46卷 2177-2193页

作者： KANIZ FATEMA ZACHARY larson JARED BARROTT Biomedical and Pharmaceutical Science Idaho State UniversityPocatello83209USA

Osteosarcoma is one of the most genomically complex cancers and as result,it has been difficult to assign genomic aberrations that contribute to disease progression and patient outcome consistently across *** potential source for correlating osteosarcoma and genomic biomarkers is within the non-coding regions of RNA that are differentially ***,it is unsurprising that a cancer classification that is fraught with genomic instability is likely to have numerous studies correlating non-coding RNA expression and function have been published on the *** review undertakes the formidable task of evaluating the published literature of noncoding RNAs in *** is not the first review on this topic and will certainly not be the *** review is organized with an introduction into osteosarcoma and the epigenetic control of gene expression before reviewing the molecular function and expression of long non-coding RNAs,circular RNAs,and short non-coding RNAs such as microRNAs,piwi RNAs,and short-interfering *** review concludes with a review of the literature and how the biology of non-coding RNAs can be used therapeutically to treat cancers,especially *** conclude that non-coding RNA expression and function in osteosarcoma is equally complex to understanding the expression differences and function of coding RNA and proteins;however,with the added lens of both coding and non-coding genomic sequence,researchers can begin to identify the patterns that consistently associate with aggressive osteosarcoma.

关键词： Osteosarcoma Epigenetics Long non-coding RNA Circular RNA MicroRNA

Himalayan Tectonics:Preface

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Geoscience Frontiers 2019年第3期10卷 791-792页

作者： Kyle larson Christopher J. Spencer Tectonics and Geodynamics Earth Environmental and Geographical Sciences IKBSAS University of British Columbia Earth Dynamics Research Group The Institute for Geoscience Research (TIGeR) Department of Applied Geology Curtin University

The Himalayan-Tibetan orogen system serves as the modern paradigm for understanding convergence-related processes in orogenic belts. The advancements made studying the region have been applied to other ancient orogenic belts leading not only to a better understanding of their development, but also of secular changes in collisional processes. As more advanced methodologies are introduced and utilized in geological research, the type, scale, and quality of data available enable quantification of geological processes not previously possible. These complex and robust datasets now form the core of many of the research projects undertaken across the Himalaya and continue to provide unprecedented insight into the myriad different aspects of the evolution of the collisional system.

关键词： Himalayan-Tibetan system evolution