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61.
锥形聚晶金刚石复合片(polycrystalline diamond compact,PDC)齿是一种具有较强抗冲击性和耐磨性的新型PDC齿,在坚硬、强研磨性和软硬交错地层中取得了非常好的钻井提速效果。为了揭示锥形齿破碎硬岩机制,开展锥形齿破碎花岗岩试验与数值模拟研究,分析了切削深度和前倾角对锥形齿切削力和破岩比能的影响规律,采用高速摄像机和透明K9玻璃观测了锥形齿作用下岩屑形成过程及微裂纹萌生与扩展过程,通过数值模拟分析了破岩过程中岩石应力响应与损伤演化特性,结合对切削槽和大尺寸块体岩屑表面形貌及断口微观特征分析,建立了锥形齿破碎花岗岩机制模型。结果表明,锥形齿破碎花岗岩的过程可以分为挤压成核和块体崩裂两个阶段,前倾角对岩石破碎过程影响较小,切削深度的影响显著;锥形齿周围的裂纹主要由压实核、纵向裂纹和横向裂纹组成,纵向裂纹和横向裂纹扩展的最大深度分别为切削深度的6.69倍和4.53倍;齿尖周围压应力集中,岩石发生压剪破坏,压应力区外围形成弧形条带状拉应力区,并在齿尖及压应力区边界处诱导出拉伸微裂纹;微裂纹向齿前扩展形成弧形拉伸主裂纹,发生块体岩屑崩裂,提高破岩效率,向岩石内部扩展劣化...  相似文献   
62.
陈新海 《探矿工程》2022,49(5):127-135
为了巴彦河套新区油气资源高效开发,(1)通过测井数据、岩心实验以及实钻数据,开展了该区地层岩性可钻性分析,表明白垩系埋深较深地层以及太古界片麻岩地层可钻性差;(2)调研了该区以及外部区块难钻地层异形齿钻头实钻情况,白垩系5000 m以深地层以及太古界地层单只钻头进尺少,机械钻速低,调研的外部区块塔里木塔河南难钻地层通过使用异形齿钻头,提速效果显著;(3)对比分析了平面齿、斧形齿、多棱齿以及锥形齿破岩机理,为后续钻头优化设计提供了理论支撑;(4)开展了异形齿PDC钻头现场实验,较常规PDC钻头单只进尺以及机械钻速均取得了显著的提升,其中有21口井实现二开“一趟钻”,总进尺30000余米。总之根据地层可钻性变化,优配平面齿、斧形齿、多棱齿以及锥形齿,提高钻头与地层的配伍性,可显著提高钻井效率。  相似文献   
63.
方学东  郝斌 《测绘科学》2010,35(2):132-133
针对民用机场净空管理过程中锥形面范围难以准确确定,主要采用手工方式绘制障碍物限制面图进行管理的问题,给出了净空管理过程中受城市建设影响较大的、形状最为复杂的锥形面范围,导出了锥形面边界的计算方法,并确定了围限锥形面的各关键点坐标,为采用计算机自动判定障碍物是否落入锥形面奠定了理论基础。  相似文献   
64.
65.
In 2001, the International Seabed Authority (ISBA) initiated the consideration relating to the Regulations for Prospecting and Exploration for Hydrothermal Polymetallic Sulphides and Cobalt-rich Ferromanganese Crusts in the Area at its 7th session. Since then, the consideration of the Regulations has been mainly focused on the size of areas to be allocated for exploration and exploitation of the crusts. This paper, based on the investigation data and the analysis of the distribution characteristics of the crusts, suggests a model for determining the size of areas for exploration and exploitation of the crusts, taking into account various factors such as production scale, crust thickness and grade, mineable area proportion, recovery efficiency, exploration venture, and so on. Through the modeling, the paper suggests that the exploration area (the area covered by each application for approval of a plan of work for exploration of cobalt-rich crusts) shall be 4 856 km2 and the exploitation area (the mine site area) shall be 1 214 km2, for 20 years of 1 million wet tonnes annual production.  相似文献   
66.
透视圆锥投影的研究   总被引:2,自引:0,他引:2  
分析了获取透视圆锥投影的原理和方法,推导出了透视切,割圆锥投影的一般公式,给出了透视切,割圆锥投影的几个特例,并对各种圆锥投 影的变形进行了比较分析。结果表明,透视圆锥投影用于小比例尺地图的制作是可行的。  相似文献   
67.
通过大洋一号船DY105--12 /14 航次采集的结壳样品,对中太平洋CL、CM2、CM3、CX、CQ、 CA、CB 海山结壳的主要成壳元素Mn、Fe、Co、Ni、Cu 的含量进行了测试统计,并与邻区的麦哲伦海山、马绍尔群岛、夏威夷群岛和莱恩群岛进行了对比,中太平洋各海山以及不同区域海山结壳的主成分之间存在一些差异,这主要与各海山结壳的物质来源、成壳环境和成壳时代的差异有关。不同形态类型的结壳主成分具有一定的差别,其主要原因可能是生长机制和形成环境不同造成的。  相似文献   
68.
Observations from 17 ALVIN dives and 14 ANGUS runs plus laboratory study of basalt samples collected with ALVIN help to constrain the morphologic, volcanic and petrologic evolution of four seamounts near the East Pacific Rise (EPR). Comparison among the four volcanoes provides evidence for a general pattern of near-EPR seamount evolution and shows the importance of sedimentation, mass wasting, hydrothermal activity and other geologic processes that occur on submerged oceanic volcanoes. Seamount 5, closest to the EPR (1.0 Ma) is the youngest seamount and may still be active. Its summit is covered by fresh lavas, recent faults and hydrothermal deposits. Seamount D is on crust 1.55 Ma and is inactive; like seamount 5, it has a breached caldera and is composed exclusively of N-MORB. Seamounts 5 and D represent the last stages of growth of typical N-MORB-only seamounts near the EPR axis. Seamounts 6 and 7 have bumpy, flattish summits composed of transitional and alkalic lavas. These lavas probably represent caldera fillings and caps overlying an edifice composed of N-MORB. Evolution from N-MORB-only cratered edifices to the alkalic stage does not occur on all near-EPR seamounts and may be favored by location on structures with relative-motion-parallel orientation.  相似文献   
69.
A new bathymetry processing software package has been developed to postprocess new GLORI-B swath bathymetry data using preexisting techniques. GLORI-B bathymetry is calculated using an interferometry (phase delay) method using the modified GLORIA towfish which has parallel rows of transducers on both sides. We describe four types of artifacts observed during the first use of this new system during Legs 5 and 6 of the Gloria Expedition which surveyed the fastest spreading segment of the global seafloor spreading system and the broad chain of volcanoes near Easter Island. These artifacts include cross-track bias, along-track bias, a 'dropped edge' effect, and random noise. We describe and illustrate how we minimize these artifacts. We merge the SeaBeam 2000 bathymetry data with the GLORI-B bathymetry data to produce a final bathymetric mosaic which covers about 243,400 km2 and shows a different style of diffuse widely spread volcanism not previously observed along hotspot chains. The data are used in several studies describing seamount morphology, elastic thickness of the lithosphere, tectonic and geochemical evolution of the area, and mantle flow from a hotspot to a superfast seafloor spreading center.  相似文献   
70.
This paper presents the fractal distribution of topography of seamounts from the West Pacific and the resource quantity of cobalt crust therein. The cobalt resource quantity has three to four variable fractal dimensions, corresponding to the distinct slopes and water depths of the seamount. The multiple fractal property of resource quantity may have resulted from various factors, such as types and components of cobalt crusts and ages of oceanic crusts hosting the seamounts. Individual seamounts display complex topography and quantity of cobalt crust, both in the same and different regions. Translated from Acta Sedimentologica Sinica, 2006, 24(5): 705–713 [译自: 沉积学报]  相似文献   
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