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111.
文章对印度尼西亚索林帕萨铜多金属矿含矿石英脉流体包裹体进行了显微测温与氢氧同位素测定,发现石英脉中含有3种类型的流体包裹体:A.纯液相水溶液包裹体;B.富液相气液两相水溶液包裹体和C.富气相气液两相水溶液包裹体,其中以B类为主.三种流体包裹体同时出现,表明石英脉形成时流体可能发生过沸腾作用.成矿流体均一温度为198.9℃~356.4℃,冰点温度为-0.6℃~-2.3℃,相应流体盐度变化范围为0.94%~3.76%NaCleq..质谱测定显示成矿流体的氢氧同位素组成分别为占δDH2O=-61.0‰~-81.0‰,δ18OH2O=-3.08‰~0.17‰,表明成矿流体主要为大气降水,不排除有少量岩浆水加入.根据成矿流体地球化学与围岩蚀变类型,初步推断该矿属于酸性-硫酸盐(高硫)型的浅成低温多金属矿床,沸腾作用是成矿物质沉淀的主要因素.  相似文献   
112.
印尼地区地震断层面上的海潮负荷应力特征   总被引:2,自引:1,他引:1       下载免费PDF全文
对印尼地区3574次M≥5.0地震震源断层面上的海潮负荷应力进行计算,研究了地震断层上的负荷应力随深度变化以及随断层倾角和走向的变化特征.结果表明,地震断层上的负荷正应力大于负荷切应力.逆断层上的负荷应力最大,其它依次为斜滑断层、正断层和走滑断层.倾角范围在0°—50°的断层上的负荷正应力随倾角增大有减小趋势,负荷切应力在30°—50°倾角范围的断层上较大.负荷应力随断层走向的趋势性变化不明显.不同类型断层上的负荷正应力和切应力在震源深度15km处均达到最大,之后随深度增加而减小.当震源深度小于40km时,断层面上的海潮负荷应力的量级与固体潮应力相当.因此指出,在潮汐应力对地震影响的研究中,对震源深度小于40km的海洋和沿海地震,除固体潮汐应力外还需要考虑海潮负荷应力的影响.  相似文献   
113.
Semeru Volcano is the highest mountain of Java (Indonesia), and a vulcanian explosion occurs every 15 minutes on average, since 1967. Thus a constantly renewed stock of material and the heavy monsoon rainfall [3700 mm yr?1 at 1500 m above sea level (a.s.l.)] provide a perfect setting for the study of lahars and their deposits. Hence, we examined the architecture of lahars' terraces 9·5 km from the summit in the Curah Lengkong Valley. We first used ground penetrating radar (GPR) over vertical exposures of the lahars cut‐bank terraces. This allowed us to better understand transversal radargrams across terraces, which are not visually accessible in the field. Preliminary results from a single radargram are very instructive, since (1) they prove that the lateral architecture does not correspond to that observed from banks only; (2) we could observe the presence of lenses and stratigraphic discontinuities; (3) the setting of the various units can also help reconstruct deposition processes and the chronology of different units. In order to finalize these preliminary results, we however need to perform multiple GPR radargrams and provide a complete set of results. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
114.
印度尼西亚红土镍矿的生成及找矿勘探   总被引:2,自引:0,他引:2  
通过对印度尼西亚东南部红土镍矿的找矿工作以及前人对红土镍矿找矿工作的总结,指出红土镍矿的生成条件及找矿勘探方法。红土镍矿是超基性岩在热带及亚热带常年高温、雨、旱交替且年降雨量较大的地区经风化、淋滤、沉积富集而成。找矿勘探工作要针对找矿区域的超基性岩进行化探次生晕扫面工作并确定矿化区。  相似文献   
115.
In 2006 Merapi volcano, Indonesia, erupted for a few months, producing several block-and-ash flows reaching a maximum distance of 7.5 km from the main vent. During the eruption, we conducted a survey on those flow deposits in the Gendol Valley at Kaliadem village, about 4.5 km from the Merapi submit, using a Ground Penetrating Radar (GPR). The upper deposit was studied in its distal reaches, whereas the one below was studied in its medial reaches. The field study was carried out with a commercial RAMAC® GPR coupled with 100 MHz antennas, and the data treatment conducted with Reflex™ software. From this survey, we determined both deposits' local (1) thickness – reaching a maximum of 15 m – and (2) internal architecture. This last one is governed by long reflecting horizons extending over 20 to 30 m that delimit layers showing progradation patterns in their distal reaches. Within these layers we could also observe an internal architecture of still unknown origin. The layers are interpreted as the result of the flow pulses that progressively deposited downstream-ward by progradation. However the interpretation of those GPR profiles is a bit hazardous, because of the absence of outcrops, and we can only proceed by analogy with other studies. Nevertheless, despite numerous limitations, GPR is a helpful tool to understand pyroclastic deposits' structure when no visual observations are available.  相似文献   
116.
2004年12月26日印尼8.7级和2007年9月12日印尼8.5级地震不同程度引起新疆地下流体和形变的同震效应。震后,水位首先出现同震水震波,而后出现大幅度上升现象;水温出现震时脉冲突升,震后小幅度下降,然后逐步过渡到一个新的稳定状态。两次印尼8级地震,前者较后者水温和水位同震波到时短、波幅大、振荡持续时间长。重力仪记录到变化幅度极大、到时和结束时相当清晰的同震震波,且初始到时在其他形变记录仪器之前,持续时间较长;倾斜和应变记录到同震阶跃,但持续时间相对较短。垂直摆正常波动时有明显的固体潮,地震波到时后固体潮畸形变化或消失,地震波基本衰减完后,重新出现明显固体潮。  相似文献   
117.
Fauna species living in seagrass meadows depend on different food sources, with seagrasses often being marginally important for higher trophic levels. To determine the food web of a mixed-species tropical seagrass meadow in Sulawesi, Indonesia, we analyzed the stable isotope (δ13C and δ15N) signatures of primary producers, particulate organic matter (POM) and fauna species. In addition invertebrates, both infauna and macrobenthic, and fish densities were examined to identify the important species in the meadow. The aims of this study were to identify the main food sources of fauna species by comparing isotopic signatures of different primary producers and fauna, and to estimate qualitatively the importance of seagrass material in the food web. Phytoplankton and water column POM were the most depleted primary food sources for δ13C (range −23.1 to −19.6‰), but no fauna species depended only on these sources for carbon. Epiphytes and Sargassum sp. had intermediate δ13C values (−14.2 to −11.9‰). Sea urchins, gastropods and certain fish species were the main species assimilating this material. Seagrasses and sedimentary POM had the least depleted values (−11.5 to −5.7‰). Between the five seagrass species significant differences in δ13C were measured. The small species Halophila ovalis and Halodule uninervis were most depleted, the largest species Enhalus acoroides was least depleted, while Thalassia hemprichii and Cymodocea rotundata had intermediate values. Fourteen fauna species, accounting for 10% of the total fauna density, were shown to assimilate predominantly (>50%) seagrass material, either directly or indirectly by feeding on seagrass consumers. These species ranged from amphipods up to the benthic top predator Taeniura lymma. Besides these species, about half of the 55 fauna species analyzed had δ13C values higher than the least depleted non-seagrass source, indicating they depended at least partly for their food on seagrass material. This study shows that seagrass material is consumed by a large number of fauna species and is important for a large portion of the food web in tropical seagrass meadows.  相似文献   
118.
The macrobenthic animal biomass of the intertidal area of the Sembilang peninsula of South Sumatra, Indonesia, has been studied in 2004. Each month (March–August) 21 core samples were taken at each of six sampling stations. Macrobenthic fauna were identified at the lowest taxonomical level possible and counted. Biomass was measured as ash-free dry mass (afdm). The average biomass over all stations and months was 3.62 g afdm m−2, the highest biomass (47.45 g afdm m−2) found at a station in one month was due to abundant occurrence of the bivalve Anadara granosa. Low biomass of macrobenthic fauna at Sembilang peninsula cannot easily be explained but is in line with low biomasses found elsewhere in the tropics. For that reason we analyzed a data set of 268 soft-bottom intertidal biomasses collected world-wide to look for a relationship with latitude. It was shown that average biomass of intertidal macrobenthic fauna in the tropics was significantly (p < 0.05) lower than that at non-tropical sites. A significant second-order relationship between biomass of macrobenthic fauna and latitude was established.  相似文献   
119.
High-pressure metamorphic rocks are exposed in Karangsambung area of central Java, Indonesia. They form part of a Cretaceous subduction complex (Luk–Ulo Complex) with fault-bounded slices of shale, sandstone, chert, basalt, limestone, conglomerate and ultrabasic rocks. The most abundant metamorphic rock type are pelitic schists, which have yielded late Early Cretaceous K–Ar ages. Small amounts of eclogite, glaucophane rock, garnet–amphibolite and jadeite–quartz–glaucophane rock occur as tectonic blocks in sheared serpentinite. Using the jadeite–garnet–glaucophane–phengite–quartz equilibrium, peak pressure and temperature of the jadeite–quartz–glaucophane rock are P  = 22 ± 2 kbar and T  = 530 ± 40 °C. The estimated P–T conditions indicate that the rock was subducted to ca 80 km depth, and that the overall geothermal gradient was ∼ 7.0 °C/km. This rock type is interpreted to have been generated by the metamorphism of cold oceanic lithosphere subducted to upper mantle depths. The exhumation from the upper mantle to lower or middle crustal depths can be explained by buoyancy forces. The tectonic block is interpreted to be combined with the quartz–mica schists at lower or middle crustal depths.  相似文献   
120.
Indonesia has maritime boundaries with 10 countries namely: Australia, Timor Leste, Papua New Guinea (PNG), Palau, Philippines, Vietnam, Thailand, Malaysia, Singapore, and India. Many treaties have been ratified concerning these boundaries. Unfortunately, many coordinates of boundary points mentioned in the treaties are not clear in relation to their geodetic datum. The uncertainty in geodetic datum of boundary points introduces complications and problems in spatial management of Indonesia's maritime boundaries, since it can displace the boundary lines from their assumed true location. This study investigates the possible original geodetic datums for the maritime boundaries between Indonesia and neighboring countries, in the case they are not explicitly stated in the treaties. The displacements of boundaries in WGS84 datum are generally in the order of a few hundred meters, i.e., about 200 to 400 m, depending on the assumed original geodetic datum being considered. These boundary displacements are spatially advantageous for Indonesia in some cases and also disadvantageous in others. The study will sum up with some conclusions and recommendations.  相似文献   
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