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燕山期由于受华夏构造自东向西仰冲作用的影响、改造作西侧伏的海西、印支褶皱带形成ＮＥ向分布、断面南倾、向西南撒开、向北东收敛,形如帚状推覆断裂带,在靠近收敛部分控制着金矿的分布。印支期金矿和碳酸盐台地礁岩的消失、礁前滑脱砾岩和火山碎屑浊积岩系上超盆地的复合、有机质的热解、分异有关,形成成岩—后生矿床;燕山晚期金矿以改造作用为主,形成后生矿床。 相似文献
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光学后向散射法在海洋现场探测无机悬浮颗粒物质的应用研究 总被引：1，自引：0，他引：1
本文论述了使用作者于１９８８年研制成功的国内第一台拖曳荧光计系统，通过改换荧光测量滤片为中性滤光片。 相似文献
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利用卫星遥感对同一地区重复成像的特点，采用从港湾不同时相的影像中提取不同潮位的水域面积的方法，建立潮位面积算式和采用分层求和的方法，建立沉 积参量算式。利用沉积参量算式和潮位面算式计算了海口港两个同时段的０ｍ以浅的沉积参量；１９６５－１９８４年时段沉积总量为４．５９×１０＾８ｍ＾３，沉积速率为２．４×１０＾５ｍ＾３／ａ；１９８４－１９９０年时段，沉积总量为－８．４×１０＾５ｍ＾３，沉积速率为－１． 相似文献
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Yu Ye Joseph R. Smyth Steven D. Jacobsen Wendy R. Panero David A. Brown Tomoo Katsura Yun-Yuan Chang Joshua P. Townsend Przemyslaw Dera Sergey Tkachev Cayman Unterborn Zhenxian Liu Céline Goujon 《Contributions to Mineralogy and Petrology》2013,166(5):1375-1388
MgSiO3 akimotoite is stable relative to majorite-garnet under low-temperature geotherms within steeply or rapidly subducting slabs. Two compositions of Mg–akimotoite were synthesized under similar conditions: Z674 (containing about 550 ppm wt H2O) was synthesized at 22 GPa and 1,500 °C and SH1101 (nominally anhydrous) was synthesized at 22 GPa and 1,250 °C. Crystal structures of both samples differ significantly from previous studies to give slightly smaller Si sites and larger Mg sites. The bulk thermal expansion coefficients of Z674 are (153–839 K) of a 1 = 20(3) × 10?9 K?2 and a 0 = 17(2) × 10?6 K?1, with an average of α 0 = 27.1(6) × 10?6 K?1. Compressibility at ambient temperature of Z674 was measured up to 34.6 GPa at Sector 13 (GSECARS) at Advanced Photon Source Argonne National Laboratory. The second-order Birch–Murnaghan equation of state (BM2 EoS) fitting yields: V 0 = 263.7(2) Å3, K T0 = 217(3) GPa (K′ fixed at 4). The anisotropies of axial thermal expansivities and compressibilities are similar: α a = 8.2(3) and α c = 10.68(9) (10?6 K?1); β a = 11.4(3) and β c = 15.9(3) (10?4 GPa). Hydration increases both the bulk thermal expansivity and compressibility, but decreases the anisotropy of structural expansion and compression. Complementary Raman and Fourier transform infrared (FTIR) spectroscopy shows multiple structural hydration sites. Low-temperature and high-pressure FTIR spectroscopy (15–300 K and 0–28 GPa) confirms that the multiple sites are structurally unique, with zero-pressure intrinsic anharmonic mode parameters between ?1.02 × 10?5 and +1.7 × 10?5 K?1, indicating both weak hydrogen bonds (O–H···O) and strong OH bonding due to long O···O distances. 相似文献
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Gianluca Iezzi Zhenxian Liu Giancarlo Della Ventura 《Physics and Chemistry of Minerals》2009,36(6):343-354
The high-pressure behavior of three synthetic amphiboles crystallized with space group P21/m at room conditions in the system Li2O–Na2O–MgO–SiO2–H2O has been studied by in situ synchrotron infrared absorption spectroscopy. The amphiboles have compositions ANa B(Na
x
Li1 − x
Mg1) CMg5 Si8 O22(OH)2 with x = 0.6, 0.2 and 0.0, respectively. The high-P experiments up to 32 GPa were carried out on the U2A beamline at Brookhaven National Laboratory (NY, USA) using a diamond
anvil cell under non-hydrostatic or quasi-hydrostatic conditions. The two most intense absorption bands in the OH-stretching
infrared spectra can be assigned to two non-equivalent O–H dipoles in the P21/m structure, bonded to the same local environment M1M3Mg3–OH–ANa, and pointing toward two differently kinked tetrahedral rings. In all samples these bands progressively merge to give a
unique symmetrical absorption with increasing pressure, suggesting a change in symmetry from P21/m to C2/m. The pressure at which the transition occurs appears to be linearly correlated to the aggregate B-site dimension. The infrared
spectra collected for amphibole B(Na0.2Li0.8Mg1) in the frequency range 50 to 1,400 cm−1 also show a series of changes with increasing pressure. The data reported here support the inference of Iezzi et al. (Am
Miner 91:479–482, 2006a) regarding a new high-pressure amphibole polymorph. 相似文献
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海上平台桶形基础负压沉贯技术的模拟试验研究方案 总被引：4，自引：0，他引：4
对海上平台桶形基础负压沉贯技术的模拟试验研究提出了初步方案,可作为本单位此项技术训端性研究工作的参考。 相似文献
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海口港纳潮量及其变化遥感研究 总被引：3，自引：0，他引：3
通过对遥感影像中提取的水域面积，结合潮汐资料建立的纳潮量算式的方法，得到海口港１９９０年纳潮量为２．５７×１０＾７ｍ＾３，１９８４年为２．９４×１０＾７ｍ＾３，１９６５的为２．６２×１０＾ｕ７ 相似文献