发震带试验(SEIZE)

对发震带试验计划(SEIZE)以及南海（Nankai）海槽的发震带钻探计划（NanTroSEIZE）进行了综述。SEIZE作为大陆边缘计划(MARGINS)的重要研究内容和综合大洋钻探计划（IODP）的优先研究领域,重点对世界主要俯冲发震带进行研究。SEIZE的主要研究内容包括：①凸凹体的物理性质;②在地震周期里,应力、应变和孔隙流体成分随时间的变化;③在俯冲逆冲断层上,发震带上界和下界的确定;④引起海啸的发震带的特征;⑤大型逆冲带地震在物质转换过程中所起的作用。NanTroSEIZE将成为IODP第一个基于立管钻探的计划,也是科学大洋钻探历史上第一个分期实施的复合钻探计划;钻入发震带的复合钻探计划将最终验证关于发震带的各种假说。      

Gas hydrate saturation at Site C0002, IODP Expeditions 314 and 315, in the Kumano Basin,Nankai trough

The degree of gas hydrate saturation at Integrated Ocean Drilling Program (IODP) Site C0002 in the Kumano Basin, Nankai Trough, was estimated from logging‐while‐drilling logs and core samples obtained during IODP Expeditions 314 and 315. Sediment porosity data necessary for the calculation of saturation were obtained from both core samples and density logs. Two forms of the Archie equation (‘quick‐look’ and ‘standard’) were used to calculate gas hydrate saturation from two types of electrical resistivity log data (ring resistivity and bit resistivity), and a three‐phase Biot‐type equation was used to calculate gas hydrate saturation from P‐wave velocity log data. The gas hydrate saturation baseline calculated from both resistivity logs ranges from 0% to 35%, and that calculated from the P‐wave velocity log ranges from 0% to 30%. High levels of gas hydrate saturation (>60%) are present as spikes in the ring resistivity log and correspond to the presence of gas hydrate concentrations within sandy layers. At several depths, saturation values obtained from P‐wave velocity data are lower than those obtained from bit resistivity data; this discrepancy is related to the presence of free gas at these depths. Previous research has suggested that gas from deep levels in the Kumano Basin has migrated up‐dip towards the southern and seaward edge of the basin near Site C0002. The high saturation values and presence of free gas at site C0002 suggest that a large gas flux is flowing to the southern and seaward edge of the basin from a deeper and/or more landward part of the Kumano Basin, with the southern edge of the Kumano Basin (the location of site C0002) being the main area of fluid accumulation.     

国家重点研发计划“深地资源勘查开采”攻关目标与任务剖析

国家重点研发计划“深地资源勘查开采”重点专项（简称“深地专项”）以大幅提升中国资源发现率和资源获取能力,全面支撑国家找矿突破战略行动为核心目标。按照国家重点研发计划“全链条设计,一体化实施”的要求,专项重点资助的研究工作包括：中国深部资源成矿成藏、预测评价与深部开采相关重大基础理论研究,航空-地面-地下立体勘查和智能化、无人化绿色采矿共性关键技术装备研发以及相关应用示范研究。“深地专项”共包含“成矿系统的三维结构与控制要素系统”等7项任务,各任务及专项的目标通过若干相互关联、有机衔接的项目落实。结合专项启动以来的立项情况,梳理了7个任务方向专项经费的分布情况,并分析总结了各任务方向的研究重点、难点和预期目标,全面呈现了“深地专项”的研究布局、空间布局和资金布局,为相关研究工作和管理工作的开展提供了参考。     

The missing half of the subduction factory: shipboard results from the Izu rear arc,IODP Expedition 350

IODP Expedition 350 was the first to be drilled in the rear part of the Izu-Bonin, although several sites had been drilled in the arc axis to fore-arc region; the scientific objective was to understand the evolution of the Izu rear arc, by drilling a deep-water volcaniclastic section with a long temporal record (Site U1437). The Izu rear arc is dominated by a series of basaltic to dacitic seamount chains up to ~100-km long roughly perpendicular to the arc front. Dredge samples from these are geochemically distinct from arc front rocks, and drilling was undertaken to understand this arc asymmetry. Site U1437 lies in an ~20-km-wide basin between two rear arc seamount chains, ~90-km west of the arc front, and was drilled to 1804 m below the sea floor (mbsf) with excellent recovery. We expected to drill a volcaniclastic apron, but the section is much more mud-rich than expected (~60%), and the remaining fraction of the section is much finer-grained than predicted from its position within the Izu arc, composed half of ashes/tuffs, and half of lapilli tuffs of fine grain size (clasts <3 cm). Volcanic blocks (>6.4 cm) are only sparsely scattered through the lowermost 25% of the section, and only one igneous unit was encountered, a rhyolite peperite intrusion at ~1390 mbsf. The lowest biostratigaphic datum is at 867 mbsf (~6.5 Ma), the lowest palaeomagnetic datum is at ~1300 mbsf (~9 Ma), and the rhyolite peperite at ~1390 mbsf has yielded a U–Pb zircon concordia intercept age of (13.6 + 1.6/?1.7) Ma. Both arc front and rear arc sources contributed to the fine-grained (distal) tephras of the upper 1320 m, but the coarse-grained (proximal) volcaniclastics in the lowest 25% of the section are geochemically similar to the arc front, suggesting arc asymmetry is not recorded in rocks older than ~13 Ma.     

基于RouterOS技术的12322防震减灾电话呼叫系统双线路设计与实现

根据12322电话呼叫系统的实际工作情况,提出了系统线路备份方案,设计了适合新疆维吾尔自治区地震局现状的12322电话呼叫系统双线路,并给出整体思路、实际配置及调试过程,该方案将会提高12322电话呼叫系统线路的稳定运行,同时也提高了系统的安全运行效率。     

Linkage of deep sea rapid acidification process and extinction of benthic foraminifera in the deep sea at the Paleocene/Eocene transition

Ocean Drilling Program Leg 199 Site 1220 provides a continuous sedimentary section across the Paleocene/Eocene (P/E) transition in the carbonate‐bearing sediments on 56–57 Ma oceanic crust. The large negative δ¹³C shift in seawater is likely due to the disintegration of methane hydrate, which is expected to be rapidly changed to carbon dioxide in the atmosphere and well‐oxygenated seawater, leading to a reduction in deep‐sea pH. A pH decrease was very likely responsible for the emergence of agglutinated foraminiferal fauna as calcareous fauna was eliminated by acidification at the P/E transition at Site 1220. The absence of the more resistant calcareous benthic foraminifera and the presence of the planktonic foraminifera at Site 1220 is interesting and unique, which indicates that calcareous benthic foraminifera suffered greatly from living on the seafloor. Box model calculation demonstrates that, assuming the same mean alkalinity as today, pCO₂ must increase from 280 ppm to about 410 ppm for the calcite undersaturation in the deep ocean and for the oversaturation in the surface ocean during the P/E transition. The calculated increased pCO₂ coincides with paleo‐botanical evidence. The current global emission rate (～7.3 peta (10¹⁵) gC/y) of anthropogenic carbon input is approximately 30 times of the estimate at the P/E transition. The results at the P/E transition give an implication that the deep sea benthic fauna will be threatened in future in combination with ocean acidification, increased sea surface temperature and more stratified surface water.     

海底天然气水合物资源量计算及环境效应评估

计算天然气水合物的资源量是比较复杂的 ,利用垂直大陆边缘横断面面积来计算水合物资源量的方法 ,能较好地反映外界条件变化所导致的水合物资源量在时间上的变化趋势。呈透镜状的水合物横断面面积主要与以下 6个参数有关 :水的活度、大陆坡深度、大陆架转折端的深度、大陆坡坡度、底部水温以及地热梯度。其中 ,前 3个参数中任何一个减小或者后 3个参数中任何一个增大都会导致横断面面积的减小。运用VisualBasic 6 0编程 ,以布莱克海岭地质背景为例 ,根据横断面面积、充填率和孔隙度计算全球海底水合物资源量约为 3 97× 10 5km3 ,与其他学者的计算结果相当。进而推算出LPTM约有 0 38× 10 5km3 的水合物被溶解并释放到海洋和大气圈中 ,导致当时沉积的碳酸盐岩和有机物的平均δ13 C下降 - 2 5‰的重大地质事件。这种水合物资源量计算方法 ,对分析地史时期类似重大转折时期评估天然气水合物对全球环境的影响 ,具有较强的启迪作用     

快速气候变化与高分辨率的深海沉积记录

通过高分辨率海洋古气候序列研究快速气候变化的机制是大洋钻探ODP及相关的国际海洋古全球变化研究IMAGES的重要贡献。研究发现,千年、百年尺度的古气候事件具有全球性,不仅见于冰芯和北大西洋高纬区,也发生在热带太平洋等其它海区和地球的其它部分;不仅见于末次冰期,也发生在全新世和早、中更新世。尽管这些快速气候变化的原因和机理尚无定论,但至少说明存在有别于冰期／间冰期冰盖体积变化的因素（如热带过程、太阳活动等）在起作用,从根本上改变了学术界对地球气候环境系统历史的认识。     

美国全球变化研究的法律基础

自1990年以来，美国全球变化研究计划（USGCRP）已经实施了10多年，并取得了丰硕的成果，这在很大程度上归因于相对完善的法律体系。一方面，《1990年全球变化研究法案》全面协调该计划在国内和国际的实施，使计划在实施的10年里获得了大量的基础科学数据和丰富的研究成果；另一方面，美国《信息自由法》、《版权法》及相关数据政策促进了全球变化研究数据和信息的共享，避免了在获取科学数据方面的重复建设，提高了数据的使用效率。在全球变化研究法案的强制要求下，美国的全球变化研究计划稳定发展、不断完善。