三维F－K域DMO方法及应用效果

在常速情况下，从三维时距方程出发，通过倾角代换，将三维倾角时差分裂为两个正交方向上的二维倾角时差，然后在这两个正交方向上分别做一次二维倾角时差校正，便可达到三维倾角时差校正的目的．应用实例表明这种三维ＤＭＯ分裂方法是切实有效的．     

三维F－K域DMO方法及应用效果

在常速情况下，从三维时距方程出发，通过倾角代换，将三维倾角时差分裂为两个正交方向上的二维倾角时差，然后在这两个正交方向上分别做一次二维倾角时差校正，便可达到三维倾角时差校正的目的．应用实例表明这种三维ＤＭＯ分裂方法是切实有效的．     

地面核磁共振找水方法在中国的应用效果

简要地阐述了地面NMR方法的直接找水原理及特点，并以实例说明了新的找水方法巳在中国11个省区地下水探查中取得出明显成效。建议在提高NMR找水仪抗电磁干扰能力和加大勘探深度方面进行研究，提高新方法的适应性。     

吉林省红旗岭镍矿区3号岩体成矿地质特征及找矿方向

吉林省红旗岭镍矿区是我国岩浆岩型铜镍硫化矿床的主要矿化集中区之一,已往勘查年中发现30余个镁铁—超镁铁质岩体,并在1号岩体中发现中型铜镍矿床、7号岩体中发现大型铜镍矿床,2号、3号、9号、32号岩体中发现小型铜镍矿床。3号岩体是本区规模较大岩体之一,通过对岩体特征的分析和对比,确定了深部镍钴矿体的找矿标志和找矿方向,为红旗岭镍矿区评价其它岩体提供依据。     

渭南阎村W7孔岩心样品的古地磁学研究

对渭南阎村W7孔岩心地层样品的磁性地层学研究,确定了黄土组、三门组地层的时代。这一地区的黄土/古土壤层形成始于松山反极性时晚期,约为1.1MaB.P.。按照地层样品的剩磁特征和岩性特征对黄土/古土壤层作更精细地划分,这一地区的黄土/古土壤层相当于马兰黄土、离石黄土层,缺失午城黄土。地层的剩磁极性资料表明,三门组地层形成于高斯极性时晚期—松山极性时中期,按照奥尔都维正极性亚时为第四纪下限的年代准则,确定三门组地层的时代为晚上新世。 W7孔岩心的地层样品的剩磁极性序列与已有的地磁极性年代表的磁极性序列大体相当,本项研究也揭示了二个短周期极性事件的存在,位于第5黄土层的安比拉事件(Emperor)发生的年代约为0.445—0.458Ma B.P.。位于第9黄土层的后期哈拉米洛事件(Post-Jaramillo)发生的年代约为0.77—0.81MaB.P.。 磁性地层学研究表明这一地区在松山反极性时中晚期出现过沉积间断,持续时约0.5Ma。 根据W7孔的地层学研究认为,选择以奥尔都维正极性亚时末期的年代(1.60MaB.P.)作为第四纪下限是有利于第四纪地层的划分和对比的。     

鄂尔多斯盆地三叠系延长组石油资源现状与勘探潜力分析

为寻求保持探明石油地质储量持续稳定增长的有效资源接替勘探领域,对鄂尔多斯盆地三叠系延长组待探明资源量的分布进行综合分析。通过对延长组5大沉积体系资源量和探明石油地质储量分布特征的对比分析,指出延长组中、下组合是近期油气勘探的主要接替层系。其中湖盆中部的长6、长8油层组和西北、西南沉积体系的长8油层组是近期增储上产的现实勘探领域;东北沉积体系的长8油层组和全盆地的长9—长10油层组是保证未来5~10年储量稳定增长的主要勘探接替领域。     

南京地震台数字与模拟记录测定震级的对比研究

分析了CTS-1宽频带数字地震仪和模拟仪器DD1、DK1记录的地震资料,发现在地震记录与大震速报方面,数字仪器可以代替原来的模拟仪器,并与模拟记录实现“无缝”连接。     

Supernova 2002ap: the first month

Supernova (SN) 2002ap in M74 was discovered on 2002 January 29. Being one of the nearest (10 Mpc) SN events in the last decades, and spectroscopically similar to the so-called 'hypernovae' 1997ef and 1998bw, both possibly associated with gamma-ray bursts (GRBs), it is of great interest. Shortly after its discovery, we launched an intensive photometric and spectroscopic monitoring campaign of this event, and here we report the results of the first month of observations. We use our UBVRI photometry to estimate the magnitudes at, and dates of, peak brightness. Our data suggest that this object reached its peak B -band luminosity on February     . Based on its similarity to SN 1998bw, we estimate the range of possible dates for a GRB that may have been associated with SN 2002ap. We find that it may include dates outside the time frame for which all available gamma-ray data have been intensively scanned, according to recent reports. The absolute magnitude at peak brightness of SN 2002ap  ( M _B =-16.9)  shows that it was significantly fainter than SN 1998bw, or normal Type Ia SNe, but similar to SN 1997ef. Our spectroscopic observations confirm that SN 2002ap is strikingly similar to SNe 1998bw and 1997ef. We briefly describe the spectral evolution of this object. To assist other observers and to stimulate theoretical models, we make our entire data set publicly available in digital form (http://wise-obs.tau.ac.il/∼avishay/local.html).     

Photometry of the Supernova SN 2002ap in M 74 during 2002

UBVR _c I _c observations of SN 2002ap during February, October, and November 2002 at the Crimean Astrophysical Observatory are reported. An examination of our photometric data, along with published data, shows that over a period of about a year from the day the SN 2002ap supernova burst, the light curve passed through three developmental stages: a sharp rise, followed by a stage of rapid exponential decrease, and then a slower fading. Based on the shape of the light curve, this supernova is of type SN I, but according to the variation in its color indices, it more likely belongs to the SN Ic supernovae. In the premaximum stage, the energy distribution from 3000 to 6000 resembles the emission from a star of spectral class F5V. In the second stage of the light curve evolution, when the brightness falls off rapidly, the changes in the color indices are associated with a change in the radiation temperature indicative of rapid cooling of the ejected material. Taking the effective radiation temperature in the premaximum stage to be T _eff 6500 K, we estimate the expansion velocity of the quasiphotosphere to be about 9700 km/s.