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261.
声波测井中的纵波和横波 总被引:2,自引:0,他引:2
充流体井中声传播理论是声波测井的理论基础。Blot(1952)绘出了充流体井中简正模式和斯通利波的频散曲线,White等(1968)首先计算了合成全波列波形,Peterson(1974)和余寿绵(1984)导出了简正模式和斯通利波的振幅表达式。余寿绵还预言纵波和横波是一种共振现象,为沿轴向传播存在特征频率的不衰减波。但是,现行理论认为纵 相似文献
262.
以成像测井资料为基础,开展了土库曼斯坦阿姆河右岸中部的中上侏罗统卡洛夫阶—牛津阶台缘斜坡礁滩沉积微相研究。首先利用岩心、薄片等资料对成像测井进行标定,在成像测井上识别出障积礁、粘结丘、高能生物碎屑滩、低能生物碎屑滩、低能砂屑滩、礁(滩)间和斜坡泥等7种沉积微相。然后通过对不同类型沉积微相的成像测井响应特征进行研究,建立了研究区碳酸盐岩成像测井相模式,主要包括亮斑相、暗斑相、低阻交错层状相、低阻变形层状相、互层相、块状相等6类,并以此为依据进行了连续的单井成像测井相划分与沉积微相解释。最后对沉积微相与储层物性关系进行了研究,认为研究区卡洛夫阶—牛津阶储层主要为裂缝-孔隙型礁滩储层,有利于储层发育的沉积微相主要为高能生物碎屑滩、低能砂屑滩、障积礁、低能生物碎屑滩和粘结丘,礁(滩)间和斜坡泥微相的岩性相对较致密,储层一般不发育。 相似文献
263.
基于GIS的城市内涝预警预报系统设计与实现 总被引:1,自引:0,他引:1
针对当前日益突出的城市内涝问题,研究开发了城市内涝预警预报系统。该系统对排水管网运行的相关参数与城区积水数据、排水管道水位信息、雨量信息以及河道水位等防汛信息数据在线监测,并实时传输到系统,当各项监测参数出现异常或超出系统设定的阈值,系统将会及时报警。同时,系统提供统一的调度平台,结合内涝与防汛数据,为管理决策提供完善的数据支持和调度平台。 相似文献
264.
The Bremen ocean bottom tiltmeter is a new 6000 m-depth deep sea instrument for autonomous observation of sea floor tilt with
signal periods longer than 7.5 s. The instrument also records vertical acceleration in the frequency range from DC to 1 Hz.
The tiltmeter has an Applied Geomechanics Inc. 756 wide angle biaxial bubble tilt sensor with a resolution of 1.0μ rad (0.2
arc second). A Kistler Corp. MEMS accelerometer of type Servo K-Beam 8330A2.5 with about 10−5m/s2 resolution is used for the acceleration measurements. An Oceanographic Embedded Systems AD24 24 bit Sigma-Delta converter,
which is controlled by a low-power Persistor Inc. embedded computer system of type CF 2, samples the data. The duration of
tiltmeter operation is more than one year, which is controlled by the battery life. In our design the tiltmeter does not need
active leveling devices, i.e., servo motors or other moving components to adjust sensors or frame. We designed the instrument
for deployments by means of a remote operated vehicle. Since May 2005 the Bremen ocean bottom tiltmeter has recorded sea floor
deformation and seismicity level in the Logatchev hydrothermal vent field, Mid-Atlantic Ridge. The tiltmeter is a part of
the monitoring system of project ‘Logatchev Long-Term Environmental Monitoring,’ called LOLEM, of the German research program
with the name ‘Schwerpunktprogramm 1144: Vom Mantel zum Ozean.’ 相似文献
265.
本文以电磁场理论为基础 ,导出了过套管进行井间地层电阻率测井问题的理论公式 ,并用低频电磁波进行了数值计算 ,分析了套管对井间电阻率测井的影响。结果表明 :用低频电磁波过套管测量地层电阻率的井间测井方法是可行的。该理论可为套管井井间地层电阻率测井仪器的研制、测井解释及井间电阻率层析成像技术提供重要的理论依据。 相似文献
266.
267.
Volcanic stratigraphy of DSDP/ODP Hole 395A: An interpretation using well-logging data 总被引:1,自引:0,他引:1
Bartetzko Anne Pezard Philippe Goldberg David Sun Yue-Feng Becker Keir 《Marine Geophysical Researches》2001,22(2):111-127
Deep Sea Drilling Project/Ocean Drilling Program Hole 395A was drilled approximately 500 m deep into young oceanic crust west
of the Mid-Atlantic Ridge. Core recovery is very poor in this hole and therefore continuous downhole measurements are important
to understand the drilled lithology. Geophysical downhole measurements were carried out during several cruises. A new set
of logs was recorded during Leg 174B in summer 1997. The new logging data show a significant improvement in data quality compared
to older measurements from Leg 109. The lithostratigraphy established from cores gives only limited information because of
the poor core recovery in this hole. The gaps in the core lithostratigraphy are filled by reconstructing a synthetic lithological
profile using the standard well-logging data. Three types of lava morphologies, massive basalts, altered lava flows, and pillow
basalts, may be distinguished using the logs because the lava morphologies show differences in their physical properties due
to differences in fracturing and alteration. The synthetic lithological profile gives a more detailed and precise vertical
definition of single layers than the core profile. The integration of further logging and core data enables a detailed reconstruction
of the accretion history at the drill site. Cyclic, upward decreasing trends in the resistivity logs were already observed
during earlier cruises and were referred to magmatic cycles. Similar trends occur in the density log and, inversely, in the
total gamma ray log. The trends reflect gradual changes in fracturing, porosity, permeability, and alteration and cover depth
intervals of several tens of meters. Boundaries between cycles are interpreted to correspond to periods of volcanic quiescence.
Two types of boundaries may be identified. Boundaries correlating with reversals in the magnetic field and/or changes in the
geochemical composition of the basalts are interpreted as long pauses. Basalts separated by these boundaries were probably
fed by separate magma reservoirs. Boundaries identified only by changes in alteration but not in geochemistry are interpreted
to represent shorter pauses. They separate basalts that were probably fed by the same magma chamber.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
268.
In conventional slowness-time coherence(STC)method,slowness and time need to be searched at the same time,which limits the precision and lowers the efficiency.The dichotomy method combined with slowness-time coherence algorithm aims to enhance the efficiency of data processing and to improve the precision.The algorithm changes the searching pattern of conventional slowness-time coherence method to acquire the slowness of component waves in array acoustic logging data.Based on energy ratio of short time window versus long time window and slowness-time coherence method,the algorithm first acquires the arrivals of the component waves using energy ratio of short time window versus long time window method.It then uses the calculated results as the arrivals in conventional slowness-time coherence method,so the slowness-time two-dimensional searching process is simplified to slowness searching process.Based on dichotomy method,the searching pattern is further optimized in replace of the ergodic searching pattern in conventional slowness-time coherence method,which means that as the iteration proceeds,the current searching interval is reduced to half of the former,so the number of searching times is decreased.The dichotomy method combined with slowness-time coherence algorithm is applied to well L in the data processing.Compared with conventional slowness-time coherence method,for compressional wave,the searching efficiency of the algorithm is 4.53 times better,while for Stoneley wave,the searching efficiency is 1.85 times better.Compared with conventional logging data,the average absolute error of the results of the dichotomy method combined with slowness-time coherence algorithm is 1.14μs/ft smaller than that of the conventional method,while the average relative error is 1.2 percent lower.The dichotomy method combined with slowness-time coherence algorithm shows good results in its application,which can enhance the processing efficiency remarkably while getting reliable results at the same time. 相似文献
269.
经过十几年技术攻关,国内页岩气录井技术发展与应用水平不断提高。本文基于地质工程一体化的评价需求,总结了具有特色的页岩气录井技术系列:岩石热解录井和自然伽马能谱录井结合的烃源岩特性评价技术;元素录井和自然伽马能谱录井结合的页岩岩性、脆性评价技术;气测录井和碳同位素录井结合的含气性评价技术;核磁录井为主的页岩物性评价技术。同时,还对页岩气录井技术发展进行了展望,认为现今页岩气录井技术面临水平井目标靶体复杂化、深层页岩气地层温度高、常压页岩气地层压力低的技术难题,需要不断提升录井仪器分辨率,加强多维核磁录井技术等录井新技术创新;为实现页岩气层的立体刻画和精确评价,需要利用大数据资源开发智能化录井工程技术系列,为页岩气高效优质勘探开发提供全面技术支撑。 相似文献
270.
准确预测碳酸盐岩储层孔隙度和渗透率对于碳酸盐岩油气藏储层评价具有重要意义。碳酸盐岩储层裂缝与溶孔广泛发育,基于经验公式从测井曲线预测储层孔隙度和渗透率具有较大误差。以中东某碳酸盐岩油藏为研究对象,选取914块取心井岩心,测定孔隙度与渗透率,利用随机森林(RF)、K-近邻(KNN)、支持向量机(SVM)和长短期记忆网络(LSTM)4种不同机器学习方法,通过测井数据进行孔隙度与渗透率预测,优化机器学习参数,筛选出适用于碳酸盐岩油藏的测井孔隙度与渗透率预测方法。研究结果表明:4种机器学习方法预测储层孔隙度结果差异不大,通过调整输入参数种类,可进一步提高孔隙度与渗透率预测效果,当以补偿中子(NPHI)、岩性密度(RHOB)和声波时差(DT)3种测井参数数据作为输入时,基于LSTM的储层孔隙度预测精度最高,孔隙度预测结果均方根误差(RMSE)为4.536 2;由于碳酸盐岩储层的强非均质性,基于机器学习的测井储层渗透率预测效果较差,相对而言,仅以NPHI作为机器学习输入参数时,基于RF的储层渗透率预测精度最高,渗透率预测结果的RMSE为45.882 3。 相似文献