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91.
井间断裂构造分析是根据测井资料,以地层分层数据为基础,利用计算机技术实现井间断裂分析的一种计算机自动分析方法.动态波形匹配算法能够很好地建立井间地层之间的对比关系,可以通过曲线拟合、特征提取、匹配代价计算等步骤,自动绘制井间地层对比的路径图解.通过对各种构造的路径图分析,总结出正断层、逆断层、不整合、同沉积断层、犁式断层和地层尖灭等34种情况下的路径图模式,提出路径图模式及相关概念. 相似文献
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沁水煤层气田枣园区块煤层气开采井产出的水具有高盐度、高矿化度的特点,直接排放可能会造成生态环境的破坏。通过连续跟踪采集枣园区块煤层气井产出水样品,并进行了25项物理化学参数的系统测试,分析了矿化度及各种阴、阳离子的动态变化规律。发现其矿化度、氯离子、钠离子浓度均呈现先高后低的变化趋势,而碳酸氢根离子的变化规律相反,呈现先低后高的特点。水化学类型呈现由Cl-Na型向Cl·HCO3-Na型和HCO3·Cl-Na型变化的规律。产出水中阳离子以K++Na+离子为主,阴离子HCO3-和Cl-值较为接近,不存在明显占绝对优势的离子。依据产出水中各离子的变化特点,依据国家Ⅱ类地表水标准,采用回归分析方法,建立了氯离子浓度排采动态变化模型。研究成果为煤层气井产出水处理技术提供了依据。 相似文献
95.
Gerardo Severino Alessandro Santini Angelo Sommella 《Stochastic Environmental Research and Risk Assessment (SERRA)》2008,22(4):567-582
Average steady source flow in heterogeneous porous formations is modelled by regarding the hydraulic conductivity K(x) as a stationary random space function (RSF). As a consequence, the flow variables become RSFs as well, and we are interested into calculating their moments. This
problem has been intensively studied in the case of a Neumann type boundary condition at the source. However, there are many
applications (such as well-type flows) for which the required boundary condition is that of Dirichlet. In order to fulfill
such a requirement the strength of the source must be proportional to K(x), and therefore the source itself results a RSF. To solve flows driven by sources whose strength is spatially variable, we
have used a perturbation procedure similar to that developed by Indelman and Abramovich (Water Resour Res 30:3385–3393, 1994) to analyze flows generated by sources of deterministic strength. Due to the linearity of the mathematical problem, we have
focused on the explicit derivation of the mean head distribution G
d
(x) generated by a unit pulse. Such a distribution represents the fundamental solution to the average flow equations, and it
is termed as mean Green function. The function G
d
(x) is derived here at the second order of approximation in the variance σ2 of the fluctuation (where K
A
is the mean value of K(x)), for arbitrary correlation function ρ(x), and any dimensionality d of the flow domain. We represent G
d
(x) as product between the homogeneous Green function G
d
(0)(x) valid in a domain with constant K
A
, and a distortion term Ψ
d
(x) = 1 + σ2ψ
d
(x) which modifies G
d
(0)(x) to account for the medium heterogeneity. In the case of isotropic formations ψ
d
(x) is expressed via one quadrature. This quadrature can be analytically calculated after adopting specific (e.g.. exponential
and Gaussian) shape for ρ(x). These general results are subsequently used to investigate flow toward a partially-penetrating well in a semi-infinite
domain. Indeed, we construct a σ2-order approximation to the mean as well as variance of the head by replacing the well with a singular segment. It is shown
how the well-length combined with the medium heterogeneity affects the head distribution. We have introduced the concept of
equivalent conductivity
K
eq(r,z). The main result is the relationship where the characteristic function ψ(w)(r,z) adjusts the homogeneous conductivity K
A
to account for the impact of the heterogeneity. In this way, a procedure can be developed to identify the aquifer hydraulic
properties by means of field-scale head measurements. Finally, in the case of a fully penetrating well we have expressed the
equivalent conductivity in analytical form, and we have shown that (being the effective conductivity for mean uniform flow), in agreement with the numerical simulations of Firmani et al. (Water Resour
Res 42:W03422, 2006). 相似文献
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大汶口盆地蕴藏着丰富的岩盐资源,岩盐矿矿层埋深较深,上覆地层为古近系巨厚的松散泥岩、砂岩,易发生遇水软化,施工难度较大。山东肥城海晶盐化有限公司实施100万t/年卤折盐采输卤工程,实施卤井7组,每组井深约3000 m。定向对接井要求精准定点造斜、连续造斜。本文介绍了对接井施工中采用的关键施工工艺及MWD无线随钻测斜仪在定向钻进中进行钻井轨迹控制的应用实例。对如何在岩盐地层钻进、螺杆钻具应用、定点造斜等关键技术措施进行了详细阐述,以期为同类型卤水对接井项目施工中提供参考。 相似文献
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低渗透储层水平井-直井联合布井技术具有广泛的应用前景,其布井方式至关重要。首先利用劈分流场的方法直观地给出常规储层水平井-直井联合布井的产能评价方法;然后针对低渗透储层的渗流特点,在考虑启动压力梯度条件下建立新的井网渗流物理模型并求解得到产能评价公式;最后经分析计算给出启动压力梯度影响的面积井网极限注采井距关系曲线。研究结果为低渗透储层部署水平井-直井联合井网提供理论依据。 相似文献