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71.
《The Journal of geography》2012,111(2):119-126
Abstract This article presents a conceptual framework that embeds ideas from world-systems theory within the larger systemic context known as the theory of dissipative structures. This article creates a theoretical perspective on global capitalism, both geographic and historical, that offers a sufficiently general and flexible model for this particular complex system in human geography. The goal is to provide a perspective that reflects the interconnectedness of individual and separate places into a larger global system that is a single functioning spatial entity. In this view, the modern world-system becomes a culmination of its past and a prologue to its future. 相似文献
72.
苏鲁超高压变质带北部地球物理调查(1)─—深反射地震 总被引:7,自引:0,他引:7
苏鲁超高压变质带是世界上研究陆一陆碰撞俯冲和壳幔作用的最佳地质场所之一.为了解超高压变质带岩石的形成、折返和相应的动力学过程,必须了解该区的地壳和浅地幔构造.本文介绍了该区北部的地质情况和进行深反射地震调查取得的成果,包括(1)在五莲─青岛断裂南侧超高压变质岩片向北倾斜,呈现叠复组构,反映岩片的折返;(2)根据地震资料推测在146Ma前后胶南地块的隆升一伸展构造内幕;(3)超高压变质岩片厚约12km,由于含有大量相辉岩透镜体,地震波速高达6.8─7.3km/s;(4)莫霍面附近有许多楔形反射体,反映陆一陆碰撞;(5)石门地区7km深处存在高波速的强反射体,可作为在该区进行大陆科学钻探的候选场址. 相似文献
73.
矾山岩浆岩型磷(铁)矿床成矿地质背景分析 总被引:1,自引:1,他引:1
在矾山磷(铁)矿床生成的海西─印支期,各方向深大断裂同时活动,为岩体和矿床源源不断地提供物源;张宣幔枝构造外围拆离滑脱带为其提供容岩空间;岩体在复盖层下的巨厚沉积盖层中分异、演化,同时伴随着印支期开阔宽缓的褶皱。它充分反映了矿床生成于准地台活化初期的大地构造背景环境。 相似文献
74.
PS测井技术是地震勘探方法之一,也是一种简便、快速、准确的原位测试技术。该文介绍了单孔法PS测井的原理及其在铁路工程勘察中的应用,主要包括根据等效剪切波,进行建筑抗震场地类别划分,铁路工程抗震场地类别划分。根据岩土动力学参数,达到评价岩体质量和划分围岩类别目的,利用剪切波速法估算岩土的承载力基本值。通过青岛机场隧道场地的工程实例说明了PS测井技术在岩土工程勘察设计中的应用情况及应用效果。 相似文献
75.
琼东南盆地深水区断层垂向输导及成藏模式 总被引:1,自引:1,他引:1
In the Qiongdongnan Basin, faults are well developed.Based on the drilling results, the traps controlled two or more faults are oil-rich. However, when only one fault cut through the sand body, there is no sign for hy-drocarbon accumulation in the sandstone. In terms of this phenomenon, the principle of reservoir-forming controlled by fault terrace is proposed, i.e., when the single fault activates, because of the incompressibility of pore water, the resistance of pore and the direction of buoyancy, it is impossible for hydrocarbon to ac-cumulate in sandstone. But when there are two or more faults, one of the faults acts as the spillway so the hydrocarbon could fill in the pore of sandstone through other faults. In total five gas bearing structures and four failure traps are considered, as examples to demonstrate our findings. According to this theory, it is well-advised that south steep slope zone of Baodao-Changchang Depression, south gentle slope zone of Lingshui Depression, north steep slope zone of Lingshui Depression, and north steep slope zone of Baodao Depression are the most favorable step-fault zones, which are the main exploration direction in next stage. 相似文献
76.
77.
In the present research, effect of silica fume as an additive and oil polluted sands as aggregates on compressive strength of concrete were investigated experimentally. The amount of oil in the designed mixtures was assumed to be constant and equal to 2% of the sand weight. Silica fume accounting for 10%, 15% and 20% of the weight is added to the designed mixture. After preparation and curing, concrete specimens were placed into the three different conditions: fresh, brackish and saltwater environments (submerged in fresh water, alternation of exposed in air & submerged in sea water and submerged in sea water). The result of compressive strength tests shows that the compressive strength of the specimens consisting of silica fume increases significantly in comparison with the control specimens in all three environments. The compressive strength of the concrete with 15% silica fume content was about 30% to 50% higher than that of control specimens in all tested environments under the condition of using polluted aggregates in the designed mixture. 相似文献
78.
79.
Seismic properties of sediments are strongly influenced by pore fluids. Stiffness of unconsolidated marine sediment increases
with the presence of gas hydrate and decreases with the presence of gas. A strong bottom-simulating reflector (BSR) observed
on a seismic profile in the Makran accretionary prism, offshore Pakistan, indicates the presence of gas hydrate and free-gas
across the BSR. Elastic properties of gas depend largely on pressure and temperature. We, therefore, first determine the elastic
modulus of gas at pressure and temperature calculated at the BSR depth in the study region. The interval velocities derived
from the seismic data are interpreted by the effective medium theory, which is a combination of self-consistent approximation
and differential effective medium theories, together with a smoothing approximation, for assessment of gas hydrate and free-gas.
The results show the saturations of gas hydrate and free-gas as 22 and 2.4% of pore space, respectively, across the BSR. 相似文献
80.