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区域可持续发展评价:进展与展望 总被引：55，自引：4，他引：55
可持续发展的评价是目前可持续发展研究的热点和前沿。当前评价可持续发展的单项指标和指标体系在指标与可持续性的关系、指标权重的选择、指标的定量化、可持续性的总体判别方法、资本替代性与替代速度、指标阈值的确定等方面具有不同的局限性 ,这也是可持续发展评价的主要难点。可持续发展的评价必然要落实到不同尺度的空间地理单元上 ,区域发展是评价的对象 ,因而可持续发展的评价必然具有显著的区域性 ,不同区域的评价指标或指标体系必然会有所不同。社会、经济与人口的发展是人类社会发展的主要目标 ,而发展的可持续性依赖于自然环境的质量 ,包括自然资源的再生或替代、生命支持系统与生物多样性的维持或改善。据此 ,论文构建了区域可持续发展评价的理论框架和发展——可持续性二维评价坐标体系 ,并提出了“自上而下”和“自下而上”的指标遴选方法。 相似文献
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一种潜在的地质压力计：流体包裹体子矿物的激光拉曼光谱测压法 总被引：8，自引：0，他引：8
高温高压下矿物的拉曼原位测量表明，某些拉曼活性的物质其拉曼位移与压力之间具有良好的线性关系。这一特性使我们能够通过测量矿物包裹体中含有这些子矿物的拉曼位移以确定矿物的形成压力。与目前常采用的共存矿物对压力计以及流体包裹体的CO2等容线法等压力测定方法相比，该方法具有快速、方便和准确的特点。由于包裹体中可以存在各种不同的子矿物以及不同的溶液物质，因此系统研究包裹体中一切可能存在的矿物或物质的拉曼位移与温度和压力之间的关系将可以提供一种方便、准确的地质压力测量手段。 相似文献
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我国境外旅游本底趋势线的建立及科学意义 总被引：49，自引：4，他引：45
提出了旅游本底趋势线的概念,依据１９７８￣１９９６年共计１９境外客流量统计数据,经过“滤波”订正,建立了外国人,港澳台胞,华侨及境外客流总量４条本底趋势线;利用旅游本底趋势表“晴雨表”功能说明‘８９风波地我国境外旅游业的影响,利用预测功能预估了未来４年我国境外旅游业的发展趋势。 相似文献
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介绍了海平面对于大气压变化的响应（反变气压计响应）的理论现状及其今后发展方向,以及反变气压计响应对于地球自转激发函数的影响。有关研究成果表明,反变气压计响应的影响具有时域、频域性,且其随时空的变化比较明显,因此,详细研究其动态特征并应用于地球物理领域的前景广阔。 相似文献
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This is a review of sea level data performed at three selected stations (Québec-Lauzon, Harrington Harbour,and Halifax) in eastern Canada in order to investigate the seasonal trends and other long-term and short-term changes which occurred since the beginning of the 20th century. Stations situated in riverine or estuarine regions (e.g., Québec-Lauzon) are significantly affected by freshwater flow in their annual cycle of sea level changes and exhibit a definite maximum in spring and minimum in autumn-winter. Other stations situated in the eastern half of the Gulf of St. Lawrence (e.g., Harrington Harbour) or near the open Atlantic coast (Halifax) mainly follow the general cycle of subarctic regions, with lows in spring-summer and highs in autumn-winter. Such seasonal variations appear to be related to the atmospheric pressure and baroclinic current variations. Secular trends in mean sea level in eastern Canadian waterbodies show a mean rise of about 2.56 mm/yr -1 due to tectonic motions, that is, land subsidence. At several stations in eastern Canada, evidence is found for the influence of the nodal tide (18.6 years), the sunspot cycle (10.8 years), the lunar perigee (8.47 years), the pole tide (14.5 months), the annual cycle (12 months), and semiannual tidal cycle (6 months) in sea level records. Beside long-term oscillations with periods of more than one year, evidence is found for high energetic semidiurnal and diurnal tides where they contribute largely (from 90-95%) to short term variability of sea level. In the residual signal (variations of sea level--tidal variations), short-term variations between 2 to 30 days can be attributed to meterological forcing (atmospheric pressure and winds), longitudinal seiches (2-10 h), atmospheric tides (12 h and 24 h) and inertial oscillations (16-18 h). A regressive model showed that the water discharge from the St. Lawrence River contributes 29% to the monthly residual sea level at Québec-Lauzon. The atmospheric pressure and winds contribute respectively 8.1% and 8.9% at this station. They contribute 52.1% and 7.7% at Harrington Harbour and 41.8% and 14.3% at Halifax. The regression coefficients of residual sea level on atmospheric pressure are respectively estimated to be -1.507 cm. ( hPa ) -1 ( - 0.345 cm. ( hPa ) -1 ), -0.776 cm. ( hPa ) -1 ( - 0.112 cm. ( hPa ) -1 ) and -0.825 cm. ( hPa ) -1 ( - 0.008 cm. ( hPa ) -1 ) at the three stations. Compared to the coefficient of the inverted barometer, estimated to be -1 cm. ( hPa ) -1 , these effects of the atmospheric pressure on sea level variations seem to be amplified at Que´bec-Lauzon by the wind effects (and water discharge) while they are reduced at Harrington Harbour and Halifax. 相似文献
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Margaret Hanrahan Gerhard Brey Alan Woodland Rainer Altherr Hans-Micheal Seitz 《Contributions to Mineralogy and Petrology》2009,158(2):169-183
An eclogite barometer has profound importance in the study of upper mantle processes and potential application to diamond
prospecting. Studies on the partitioning of Li between clinopyroxene (cpx) and garnet (grt) in natural samples have shown
that this particular element is very sensitive to changes in pressure and could be calibrated as the barometer demanded for
bimineralic eclogites. Experiments were performed from 4 to 13 GPa and 1,100–1,400°C in the CMAS (CaO, MgO, Al2O3, SiO2) system with Li added as Li3PO4 to quantify this pressure dependence into a barometer expressed in the following equation: P = (0.00255T – ln K
d)/0.2351 where P is in GPa, T is in °C and K
d is defined as the partition coefficient of Li (in ppm) between clinopyroxene and garnet. The experimental pressures are reproduced
to ±0.38 GPa (1σ) by this equation. This barometer is strictly applicable only to CMAS. Experiments at 1,300°C, 8–12 GPa showed
that Henry’s Law is fulfilled for Li partitioning between cpx and grt in the concentration range of approximately 0.01–1 wt%
Li. Direct application of the equation to experiments in natural systems performed at 1,300°C from 4 to 13 GPa consistently
overestimates pressures by approximately 2 GPa.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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Monomineral universal clinopyroxene and garnet barometers for peridotitic,eclogitic and basaltic systems 总被引：1，自引：1，他引：0
I.V. Ashchepkov T. Ntaflos A.M. Logvinova Z.V. Spetsius H. Downes N.V. Vladykin 《地学前缘(英文版)》2017,8(4):775-795
New versions of the universal Jd-Di exchange clinopyroxene barometer for peridotites,pyroxenites and eclogites,and also garnet barometer for eclogites and peridotites were developed.They were checked using large experimental data sets for eciogitic(~530) and peridotitic systems(650).The precision of the universal Cpx barometer for peridotites based on Jd-Di exchange is close to Cr-Tschermalite method produced by Nimis and Taylor(2000).Cpx barometer was transformed by the substitution of major multiplier for K_D by the equations dependent from Al-Na-Fe.Obtained equation in combination with the thermometer of Nimis and Taylor(2000) allow to reconstruct position of the magma feeder systems of the alkali basaltic magma within the mantle diapirs in modern platforms like in Vitim plateau and other Southern Siberia localities and several localities worldwide showing good agreement of pressure ranges for black and green suites.These equations allow construct PTX diagrams for the kimberlite localities in Siberia and worldwide calculating simultaneously the PT parameters for different groups of mantle rocks.They give very good results for the concentrates from kimberlite lamproites and placers with mantle minerals.They are useful for PT estimates for diamond inclusions.The positions of eclogite groups in mantle sections are similar to those determined with new Gar—Cpx barometer produced by C.Beyer et al.(2015).The Fe rich eclogites commonly trace the boundary between the lower upper parts of subcontinental lithospheric mantle(SCLM) at 3-4 CPa marking pyroxenite eclogites layer.Ca-rich eclogites and especially grospydires in SCLM beneath Precambrian kimberlites occurs near pyroxenite layer but in younger mantle sections they became common in the lower parts.The diamondiferous Mg Cr-less group eclogites referring to the ancient island arc complexes are also common in the middle part of mantle sections and near 5-6 GPa.Commonly eclogites in lower apart of mantle sections are remelted and trace the high temperature convective branch.The Mg-and Fe-rich pyroxenites also show the extending in pressure trends which suggest the anatexic melting under the influence of volatiles or under the interaction with plums. 相似文献
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岩浆绿帘石特征及其地质意义研究进展 总被引：5，自引：0，他引：5
综述了国际上对岩浆绿帘石的研究成果，总结了岩浆绿帘石的特征及其在花岗质岩浆中的结晶行为，讨论了岩浆绿帘石的地质意义。岩浆绿帘石的稳定与岩浆成分、fH2O以及fO2关系密切。它通常作为中、高压近固相线结晶矿物，主要产于英云闪长岩、花岗闪长岩、花岗岩等钙碱性花岗质岩石中。该矿物在岩浆中的结晶可早可晚（相对于黑云母或角闪石），氧逸度的高低直接影响到它在岩浆中的最小稳定压力。作为早期结晶的矿物，绿帘石不能作为压力计来反映岩体侵位深度，因为在绿帘石晶出时，岩浆中液相体积在50%～80%，这样岩浆可能会有快速侵位的过程，但它的地质意义在于能够对岩浆上升速率做出估算。而晚期近固相线晶出的绿帘石时，能够作为压力计反映岩体最小侵位深度。据此可以应用于对地壳演化和隆升的研究。由于氧逸度对绿帘石的稳定有很大影响，因此在能够作为压力计时，首先需要确定岩浆氧逸度情况。通常磁铁矿型花岗岩最小侵位深度在3×108 Pa左右（10 km），而钛铁矿型为5×108 Pa以上(17～20 km)。 相似文献
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赞皇变质杂岩区西南部斜长角闪岩的地球化学、变质演化研究及其构造意义 总被引：2，自引：2，他引：0
赞皇变质杂岩位于华北克拉通中部造山带中南段,阜平杂岩以南,太古代变质岩石在该杂岩区仅有零星出露。目前研究发现,在赞皇变质杂岩的西南部地区亦有太古代(含榴)斜长角闪岩出露,且与东南部的斜长角闪岩具有类似的地球化学性质,其原岩为亚碱性玄武质岩石,形成于岛弧构造环境。岩石中石榴石保留微弱的进变质生长环带,且记录了进变质、峰期变质和退变质三个阶段的矿物组合。不同阶段的温压估算结果分别为:进变质阶段约679℃和8.4kbar,高峰期变质条件位于高角闪岩相,最高温度超过702℃、最高压力大于9.3kbar,退变质阶段温度为633～636℃、压力为5.2～5.4kbar。该地区含榴斜长角闪岩拥有典型的顺时针近等温减压型(ITD)的变质作用P-T轨迹,推测赞皇变质杂岩可能卷入了华北克拉通东部陆块和西部陆块之间的俯冲-碰撞-快速隆升过程。同时,早期进变质作用阶段信息的保留为俯冲过程的存在提供了新的证据。 相似文献
10.
Saskia Erdmann Rucheng Wang Fangfang Huang Bruno Scaillet Kai Zhao Hongsheng Liu Yan Chen Michel Faure 《Comptes Rendus Geoscience》2019,351(8):551-561
Constraining crystallization pressure and thus intrusion depth of granites in various geodynamic settings remains challenging, yet important to further our understanding of magma system and crustal evolution. We propose that titanite, which is a common accessory in metaluminous and weakly peraluminous granites, can be used as a barometer if it crystallized in magmatic, near-solidus conditions and in equilibrium with amphibole, plagioclase, K-feldspar, quartz, biotite, and magnetite ± ilmenite. Titanite Al2O3 increases with pressure (P) according to: P (in MPa) = 101.66 × Al2O3 in titanite (in wt%) + 59.013 (R2 = 0.83) with estimated uncertainties of ~±60 to ~±100 MPa for crystallization between ~150 and 400 MPa. We highlight that the current calibration dataset is limited, and that systematic experimental studies are needed to rigorously quantify the relation. The most important use of this empirical barometer will be for rocks in which amphibole is present but significantly altered, or in combination with amphibole barometry, as titanite can be easily dated by LA-ICP-MS. 相似文献
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