中国强降水过程时空集中度气候趋势

基于日降水资料序列提出一种度量不同强度降水过程时空集中程度的指标,根据中国740个气象站逐日降水资料研究分析了我国强降水过程集中度和集中期及其相关统计特征,结果表明暴雨过程年内集中度与年降水量正相关区与中国降水空间分布有很好的一致性;在对大范围洪涝灾害研究方面,暴雨过程年内集中度和集中期在定量地表征降水量在时空场上的非均匀性时有更高分辨力; 暴雨过程年内集中度比较清晰地反映出长江流域、江淮地区洪涝增加的趋势及黄河中下游、华北强降水减少的趋势。该方法可直接应用到评估水旱灾害及其气候影响等领域。     

庐枞盆地A型花岗岩与铀成矿关系

分别对庐枞盆地A型花岗岩的微量元素特征、形成时间、放射性特征等方面和已知铀矿床的成矿时间、空间分布特征、矿床成矿流体等方面资料进行了研究,分析了两者间相互关系,认为庐枞盆地A型花岗岩和铀成矿关系密切,两者在形成时间相近,空间分布相依,成因相联。     

廊固凹陷沙四晚期构造应力场模拟及低级序断层预测

在了解区域构造背景、分析断层活动特征及构造演化特征的基础上,对廊固凹陷沙四晚期构造应力场进行数值模拟,并对低级序断层发育进行预测。研究结果表明,研究区在沙四晚期活动的主要断层包括大兴断层、半截河断层等6条,牛北斜坡构造带与河西务构造带在该时期隆起明显,综合分析可知该时期最小主应力方向为SE144°—NW324°;低级序断层发育受最小主应力、剪应力等的影响,最小主应力和最大主应力与最小主应力的差值控制断层的优势发育区,平面剪应力控制断层走向,该区主要发育北北东—北东走向的断层;剖面剪应力在大部分区域为左旋,表明断层视倾向以北西向为主。     

柴达木盆地北缘晚海西—印支期古构造应力分析

为了更好认识柴北缘晚海西—印支期古构造应力特征与演化过程,在天峻快日玛乡、城墙沟、石灰沟等地区详细野外观测的基础上,利用地层恢复和古构造应力反演技术对柴北缘及邻区石炭系—新生界构造观测数据进行分析。结果表明晚二叠世—中三叠世,柴北缘在南—北向挤压作用下向北俯冲碰撞,盆地内部上二叠—中三叠统缺失。晚三叠世开始,西秦岭斜向碰撞柴达木盆地,柴北缘进入造山阶段,所受挤压作用方向转变为北西—南东向,盆地内大范围缺失上三叠统。晚海西—印支期柴北缘内部二叠纪—三叠纪地层大面积剥蚀加之该期强烈挤压作用造成尕海南山石炭系与白垩系、旺尕秀煤矿石炭系与侏罗系之间的角度不整合,意味着下伏石炭系可能遭受强烈破坏。     

南极长城站能见度变化分析

利用南极长城站1986—2012年能见度人工观测资料,分析了能见度的变化特征和趋势。结果显示,高于10 km能见度出现频率为61.0%,低于1 km的频率为8.0%。11—3月能见度较好,6—10月能见度较差;海雾和降水是夏季能见度降低的主要原因,冬季则主要归因于频繁的降雪、吹雪或雪暴等灾害性天气。10 km能见度发生频数有显著减小倾向,10 km能见度呈上升趋势,且冬季的上升速度最快,大雾、吹雪和降雪减少是主导冬季能见度升高趋势的重要因素。长城站能见度显著的天气尺度周期为2.1—8.3 d,年际变化周期为2 a、4.1 a和6.9—8.2 a,又以4.1 a最为显著。2012年开展的能见度自动观测实验表明,20 km范围内的自动观测精度较高,适用于长城站的连续监测。     

四川盆地中三叠统雷口坡组雷三、雷四段盐岩沉积环境与成因研究

四川盆地雷口坡组大量钻井资料揭示中三叠统雷口坡组主要成盐期分别为雷三2期和雷四2期。岩性组合特征、沉积环境研究表明,在川中的平昌—南充—遂宁一带发育雷三2期浓缩盐膏质蒸发泻湖微相,在川中-川西地区的南部—盐亭—成都—邛崃地区发育雷四2期盐膏湖盆微相。两期盐岩差异主要表现是,雷三2期时,盆地处于频繁的海进、海退过程中,沉积环境变化较快,成盐环境相对开放,盐盆往往多次蒸发浓缩、补给、淡化,海水表现出接近或者达到盐岩沉积浓度,其间往往夹杂石膏和云质团块沉积。雷四2期时,四川盆地处于持续的海退蒸发期,蒸发量远远大于补给量,海水以蒸发浓缩为主,海水表现为超过石盐沉积浓度,沉积石盐中夹杂卤石,局部地区钾含量极高。     

Histological Observation of Germ Cell Development and Discovery of Spermatophores in Ovoviviparous Black Rockfish（Sebastes schlegeli Hilgendorf） in Reproductive Season

Black rockfish（Sebastes schlegeli） is an important species for culture; however, its reproductive characteristics have not been fully documented. In this study, we investigated the morphology and developmental process of germ cells in this ovoviviparous rockfish in reproductive season（October 2011–November 2012） with histological methods. We found that the gonad of mature fish showed notable seasonal changes in developmental characteristics and morphological structure. The sperm cells matured during a period lasting from October to December, significantly earlier than the oocytes did. A large number of spermatozoa and other cells occurred in testis at different developmental stages. Vitellogenesis in oocytes began in October, and gestation appeared in April next year. Spermatophores were discovered for the first time in Sebastes, which assembled in testis, main sperm duct, oviduct and genital tract, as well as ovarian cavity in October and April. These organs may serve either as production or hiding places for spermatophores and spermatozoa which were stored and transported in form of spermatophores. Testicular degeneration started from the distal part of testis in April, with spermatophores assembled in degenerating testis and waiting for transportation. The copulation probably lasted for a long period, during which the spermatozoa were discharged in batches as spermatophores. These spermatophores were coated with sticky materials secreted from the interstitial areas of testis and the main sperm duct, then transported into ovary.     

Sedimentary characteristics of relict deposits on the western South Yellow Sea

Integrated studies of vertical sedimentary sequences, grain sizes, and benthic foraminifera and ostracoda, in combination with AMS 14C dating, and 210Pb and 137Cs analysis were carried out in three vibracores taken from the area of relict deposits on the western South Yellow Sea. The relict sands, which are about 0.4 m thick, overlie on the Early Holocene coastal marsh or tidal flat deposits with an evident erosional interface in between. The middle and upper parts or sometimes the whole of the relict sands have been reworked under the modern dynamic environment. The sedimentation rate varies between 0.20–0.30 cm year-1. The relict sands show a bimodal grain-size distribution pattern in frequency curves, with a sharp peak in the coarse fraction between 3Φ and 4Φ and a secondary peak in the fine fraction of about 7Φ. Of the benthic foraminiferal and ostracod assemblages, the reworked relict sands are characterized by the mixing of the nearshore euryhaline shallow-water species and deeper water species. The erosional interface at the bottom of the relict sands is considered as a regional ravinement surface formed during the transgression in the Early Holocene due to shoreface retreating landwards. The relict sands were accumulated on the ravinement surface during the transgression in the deglaciation period as lag deposits after winnowing and reworking by marine dynamic processes. And the secondary peak of fine fraction in the frequency curve for the relict sands suggests the input of fine-grained sediments during the reworking process. As the conclusion, the relict sands in the study area are interpreted as a type of reworked relict sediments.     

恒星日滤波的修正以及对高频GPS定位的影响研究

对现有的恒星日滤波方法进行了修正,提出了利用站点获得的卫星星历分段计算卫星平均轨道周期的方法。实例结果表明,相比修正前的恒星日滤波,修正后的滤波可更有效地提高定位精度,坐标三分量(N、E、U)分别提高了4.5%、5.2%和6.2%,而且在0.001～0.08 Hz频率域上也可获得更好的效果。     

二维正方晶格光控太赫兹波调制器

2006年冬季在南京北郊盘城利用系留气球探测系统、自动气象站等仪器对雾日和非雾日的边界层进行了监测,对比分析了两者的边界层结构。结果表明,非雾日主要为单层贴地逆温,并时常出现短时的双层结构,雾发展成熟时逆温则脱离地面。与非雾日相比,雾日平均雾顶之上温度日较差增大,雾顶之下则减小。平均风速的时间—高度分布在雾日和非雾日类似,在稳定性边界层中风速随高度出现一个或者两个极大值区。温度和比湿在非雾日没有显著的对应性,而在雾体内具有较好的对应关系,在雾顶升降过程中反相关。较强的逆温、较低的温度和较小的近地层风速是南京冬季成雾的背景条件。