Kuqa depression bears not only plenty ofnatural gas, but also a large amount of condensate and smallquantity of crude oil. Based on the geochemical correlationbetween the Jurassic and Triassic terrestrial hydrocarbons...Kuqa depression bears not only plenty ofnatural gas, but also a large amount of condensate and smallquantity of crude oil. Based on the geochemical correlationbetween the Jurassic and Triassic terrestrial hydrocarbonsource rock, this paper confirms that the natural gas in Kuqadepression belongs to coal-type gas and the main gas sourcerock is attributed to the middle to lower Jurassic coal seriesformation, while the main oil source rock is the upper Tri-assic lacustrine mudstone. The authors indicated that Kuqadepression was slowly subsided in Mesozoic, but rapidlywent down in Late Tertiary, which made the Jurassic andTriassic source rock suddenly deep-buried and rapidlyevolved to high and over-mature phase since 5 Ma. TheTriassic source rock is postponed to the Early Miocene dur-ing 23-12 Ma when entering the oil-generating peak, whilethe Jurassic is suspended to the latest 5 Ma, especially since2.5 Ma to the dry gas-generating period, which is one of thecharacteristics of the source rock thermal evolution in Kuqadepression. This paper presents a two-stage trapping andlate gas trapping model in Kuqa depression whose charac-teristics are: The main oil and gas reservoirs have differentsources. The oil reservoir is formed early while the gas res-ervoir is formed lately. During the early stage, it, mainly asoil, takes long distance lateral migration, while in the laterstage, it, mainly as gas, takes the vertical migration and alsohas lateral migration. The trap formed in different time onthe south and north sides of the depression and evolved intoa distributional pattern with oil in the south part and gas inthe north, also oil on the outer ring and gas on the inner ring.This paper points out that the late trapping of the naturalgas in Kuqa depression is favorable for the preservation oflarge gas fields.展开更多
Optical trapping describes the interaction between light and matter to manipulate micro-objects through momentum transfer.In the case of 3D trapping with a single beam,this is termed optical tweezers.Optical tweezers ...Optical trapping describes the interaction between light and matter to manipulate micro-objects through momentum transfer.In the case of 3D trapping with a single beam,this is termed optical tweezers.Optical tweezers are a powerful and noninvasive tool for manipulating small objects,and have become indispensable in many fields,including physics,biology,soft condensed matter,among others.In the early days,optical trapping was typically accomplished with a single Gaussian beam.In recent years,we have witnessed rapid progress in the use of structured light beams with customized phase,amplitude,and polarization in optical trapping.Unusual beam properties,such as phase singularities on-axis and propagation invariant nature,have opened up novel capabilities to the study of micromanipulation in liquid,air,and vacuum.We summarize the recent advances in the field of optical trapping using structured light beams.展开更多
文摘Kuqa depression bears not only plenty ofnatural gas, but also a large amount of condensate and smallquantity of crude oil. Based on the geochemical correlationbetween the Jurassic and Triassic terrestrial hydrocarbonsource rock, this paper confirms that the natural gas in Kuqadepression belongs to coal-type gas and the main gas sourcerock is attributed to the middle to lower Jurassic coal seriesformation, while the main oil source rock is the upper Tri-assic lacustrine mudstone. The authors indicated that Kuqadepression was slowly subsided in Mesozoic, but rapidlywent down in Late Tertiary, which made the Jurassic andTriassic source rock suddenly deep-buried and rapidlyevolved to high and over-mature phase since 5 Ma. TheTriassic source rock is postponed to the Early Miocene dur-ing 23-12 Ma when entering the oil-generating peak, whilethe Jurassic is suspended to the latest 5 Ma, especially since2.5 Ma to the dry gas-generating period, which is one of thecharacteristics of the source rock thermal evolution in Kuqadepression. This paper presents a two-stage trapping andlate gas trapping model in Kuqa depression whose charac-teristics are: The main oil and gas reservoirs have differentsources. The oil reservoir is formed early while the gas res-ervoir is formed lately. During the early stage, it, mainly asoil, takes long distance lateral migration, while in the laterstage, it, mainly as gas, takes the vertical migration and alsohas lateral migration. The trap formed in different time onthe south and north sides of the depression and evolved intoa distributional pattern with oil in the south part and gas inthe north, also oil on the outer ring and gas on the inner ring.This paper points out that the late trapping of the naturalgas in Kuqa depression is favorable for the preservation oflarge gas fields.
基金We thank Professor Kishan Dholakia for his instructive advice and help on the preparation of the manuscript.Y.Y thanks Dr.Leiming Zhou for the helpful discussion.This work was supported by the National Natural Science Foundation of China(11874102 and 61975047)the Sichuan Province Science and Technology Support Program(2020JDRC0006)the Fundamental Research Funds for the Central Universities(ZYGX2019J102).M.C.and Y.A.thank the UK Engineering and Physical Sciences Research Council for funding.
文摘Optical trapping describes the interaction between light and matter to manipulate micro-objects through momentum transfer.In the case of 3D trapping with a single beam,this is termed optical tweezers.Optical tweezers are a powerful and noninvasive tool for manipulating small objects,and have become indispensable in many fields,including physics,biology,soft condensed matter,among others.In the early days,optical trapping was typically accomplished with a single Gaussian beam.In recent years,we have witnessed rapid progress in the use of structured light beams with customized phase,amplitude,and polarization in optical trapping.Unusual beam properties,such as phase singularities on-axis and propagation invariant nature,have opened up novel capabilities to the study of micromanipulation in liquid,air,and vacuum.We summarize the recent advances in the field of optical trapping using structured light beams.