The origin and depositional characteristics of supported conglomerates in the Mahu Sag, Junggar Basin, Xinjiang, China, are examined. Based on the terminological comparison, modern sedimentary survey and core descript...The origin and depositional characteristics of supported conglomerates in the Mahu Sag, Junggar Basin, Xinjiang, China, are examined. Based on the terminological comparison, modern sedimentary survey and core description, the initial connotation and similarities and differences in definition between supported conglomerates and other similar concepts are discussed, the modern sedimentary environment in which supported conglomerates develop is analyzed, and the sedimentological characteristics of supported conglomerates formed in different depositional environments revealed by the cores of Mahu conglomerate oil field in the Junggar Basin are described. The supported conglomerate is similar in texture to grain supported conglomerate and openwork conglomerate but has differences from them, so it is suggested to keep the term "supported conglomerate", but the formation mechanism of supported conglomerate needs to be re-examined. Through field survey of modern sediments in Baiyanghe alluvial fan, Huangyangquan alluvial fan, and Wulungu Lake in Xinjiang, it is found that supported gravels not only formed by flooding events but also by sieving, avalanching, fluvial sorting as well as wind and wave reworking in the depositional environments such as inter-mountain creek, colluvium fan, gravel channel on gobi and the fan surface, lake beach, delta front, subaerial debris flow and subwater grain-flow etc. Supported gravels could form supported conglomerate after being buried. Supported conglomerates of seven different origins have been recognized in the cores of the Triassic and Permian stratum of Mahu Depression, Junggar Basin, namely, supported conglomerates in gravel channel deposits, in wind reworked channel deposits, in gravel beach bar deposits, in wave reworked delta front deposits, in mouth bar deposits and in debris flow deposits respectively. The study shows the supported conglomerates may be formed by a single depositional event or by multi-events during the post-depositional sedimentary reworking and even in diagenesis stage. Through flume experiment, numerical simulation, empirical model and modern sediment survey, infiltration process of gravelly channel can be reconstructed and the primary pore structure of supported gravel can be estimated. Statistics on physical properties of various types of reservoirs in Triassic Baikouquan Formation of Mahu oilfield show that granule conglomerate and pebbly conglomerate have higher porosity and permeability, while the cobble and coarse pebble conglomerate have lower permeability, which indicates that the supported gravels are easy to be reworked by post depositional filtration and diagenesis, and thus decrease in porosity and permeability.展开更多
The environmental potential of perforated surfaces in the tropics is noticeable. They allow obtaining higher attenuation and spatial dispersion of both direct and diffuse lighting in indoor spaces, whereas in outdoor ...The environmental potential of perforated surfaces in the tropics is noticeable. They allow obtaining higher attenuation and spatial dispersion of both direct and diffuse lighting in indoor spaces, whereas in outdoor areas, the openwork elements reduce surfaces temperature and mitigate the characteristic glare of smooth surfaces when exposed to sunlight. Openwork walls have an immense sustainability potential in modern tropical buildings： they limit the solar rays＇ admission, as well as provide an advantageous use of natural light and cross ventilation, but the research on their solar behavior is scarce. In order to obtain suitable levels of solar gain, relationships among shape, proportion, thickness and partitions composing openwork elements must be studied. This research evaluates solar gain in perforated surfaces by defining the ＂solar applicability range＂, a property useful to identify intervals of guidance where a perforated pattern shape will present a definite solar gain, giving valuable input in the geometric design of openwork elements and introducing shade performance in the design of openwork walls. Results give geometric guidelines that allow to widen the solar applicability range of a perforation pattern and to define two perforation features that have impact on the solar performance of perforated surfaces： focalization and solar performance shift.展开更多
基金Supported by the the National Natural Science Foundation of China(41772094)China National Science and Technology Major Project(2016ZX05027-002-007)
文摘The origin and depositional characteristics of supported conglomerates in the Mahu Sag, Junggar Basin, Xinjiang, China, are examined. Based on the terminological comparison, modern sedimentary survey and core description, the initial connotation and similarities and differences in definition between supported conglomerates and other similar concepts are discussed, the modern sedimentary environment in which supported conglomerates develop is analyzed, and the sedimentological characteristics of supported conglomerates formed in different depositional environments revealed by the cores of Mahu conglomerate oil field in the Junggar Basin are described. The supported conglomerate is similar in texture to grain supported conglomerate and openwork conglomerate but has differences from them, so it is suggested to keep the term "supported conglomerate", but the formation mechanism of supported conglomerate needs to be re-examined. Through field survey of modern sediments in Baiyanghe alluvial fan, Huangyangquan alluvial fan, and Wulungu Lake in Xinjiang, it is found that supported gravels not only formed by flooding events but also by sieving, avalanching, fluvial sorting as well as wind and wave reworking in the depositional environments such as inter-mountain creek, colluvium fan, gravel channel on gobi and the fan surface, lake beach, delta front, subaerial debris flow and subwater grain-flow etc. Supported gravels could form supported conglomerate after being buried. Supported conglomerates of seven different origins have been recognized in the cores of the Triassic and Permian stratum of Mahu Depression, Junggar Basin, namely, supported conglomerates in gravel channel deposits, in wind reworked channel deposits, in gravel beach bar deposits, in wave reworked delta front deposits, in mouth bar deposits and in debris flow deposits respectively. The study shows the supported conglomerates may be formed by a single depositional event or by multi-events during the post-depositional sedimentary reworking and even in diagenesis stage. Through flume experiment, numerical simulation, empirical model and modern sediment survey, infiltration process of gravelly channel can be reconstructed and the primary pore structure of supported gravel can be estimated. Statistics on physical properties of various types of reservoirs in Triassic Baikouquan Formation of Mahu oilfield show that granule conglomerate and pebbly conglomerate have higher porosity and permeability, while the cobble and coarse pebble conglomerate have lower permeability, which indicates that the supported gravels are easy to be reworked by post depositional filtration and diagenesis, and thus decrease in porosity and permeability.
文摘The environmental potential of perforated surfaces in the tropics is noticeable. They allow obtaining higher attenuation and spatial dispersion of both direct and diffuse lighting in indoor spaces, whereas in outdoor areas, the openwork elements reduce surfaces temperature and mitigate the characteristic glare of smooth surfaces when exposed to sunlight. Openwork walls have an immense sustainability potential in modern tropical buildings： they limit the solar rays＇ admission, as well as provide an advantageous use of natural light and cross ventilation, but the research on their solar behavior is scarce. In order to obtain suitable levels of solar gain, relationships among shape, proportion, thickness and partitions composing openwork elements must be studied. This research evaluates solar gain in perforated surfaces by defining the ＂solar applicability range＂, a property useful to identify intervals of guidance where a perforated pattern shape will present a definite solar gain, giving valuable input in the geometric design of openwork elements and introducing shade performance in the design of openwork walls. Results give geometric guidelines that allow to widen the solar applicability range of a perforation pattern and to define two perforation features that have impact on the solar performance of perforated surfaces： focalization and solar performance shift.
