Stochastic evaluation of fluvial to marginal marine sealing facies

Hydrocarbon top seal analyses are particularly difficult in fluvial and marginal marine settings. Although these settings often contain beds comprised of a low-permeability, clay-rich lithology associated with high quality seals, their presence does not guarantee an effective seal because individual beds within the stratal unit may be laterally discontinuous. Lateral facies changes, truncation of fine-grained beds, or the presence of crevasse splays may provide cross-stratal migration pathways, reducing the effective sealing capacity to a magnitude less than the closure height.     

Modeling an atypical petroleum system: A case study of hydrocarbon generation,migration and accumulation related to igneous intrusions in the Neuquen Basin,Argentina

In the Altiplanicie del Payún area (Neuquen Basin, Argentina), immature source rock sections intruded by up to 600 m thick Tertiary laccoliths show full spectrum maturity aureoles over hundreds of meters from the contacts. Commercial oil accumulations (20–33°API) and oil shows are located along the entire column, both in sandstone/carbonate and fractured igneous reservoirs. A challenging numerical model that included the emplacement of the intrusive bodies, with extreme temperature ranges and unusually short calculation time steps, has been done with the aim to better understand hydrocarbon generation and migration processes related to these thermal anomalies.     

A control-volume finite-element method for three-dimensional multiphase basin modeling

In this paper we describe a 3D control-volume finite-element method to solve numerically the coupled partial differential equations (PDEs) governing geological processes involved in the evolution of sedimentary basins. These processes include sediment deposition and deformation, hydrocarbon generation, multiphase fluid flow, and heat transfer in deforming porous media.     

春晓气田泥岩垮塌测井数据校正及应用

由于存在部分泥岩井眼垮塌,东海春晓气田测井曲线砂泥岩阻抗部分叠置。针对这一现象,采用未垮塌段泥岩伽马与密度拟合关系校正垮塌段泥岩密度,声波时差经本区伽德那公式拟合后求取。通过泥岩垮塌测井数据校正前后对比、直方交会、岩石物理、正演及反演效果分析,认为校正后的测井数据比较真实地反映垮塌段扩径泥岩地层特征,储层与围岩波阻抗差异明显,为储层反演、砂体空间展布分析提供了有力依据。     

1997–1998 El Niño off Peru: A numerical study

An eddy-resolving numerical simulation for the Peru–Chile system between 1993 and 2000 is analyzed, mainly for the 1997–1998 El Niño. Atmospheric and lateral oceanic forcings are realistic and contain a wide range of scales from days to interannual. The solution is validated against altimetric observations and the few in situ observations available. The simulated 1997–1998 El Niño closely resembles the real 1997–1998 El Niño in its time sequence of events. The two well-marked, sea-level peaks in May–June and November–December 1997 are reproduced with amplitudes close to those observed. Other sub-periods of the El Niño seem to be captured adequately. Simple dynamical analyses are performed to explain the 1997–1998 evolution of the upwelling in the model. The intensity of the upwelling appears to be determined by an interplay between alongshore, poleward advection (related to coastal trapped waves) and wind intensity, but also by the cross-shore geostrophic flow and distribution of the water masses on a scale of 1000 km or more (involving Rossby waves westward propagation and advection from equatorial currents). In particular, the delay of upwelling recovery until fall 1998 (i.e., well after the second El Niño peak) is partly due to the persistent advection of offshore stratified water toward the coast of Peru. Altimetry data suggest that these interpretations of the numerical solution also apply to the real ocean.     

Review of recent findings on the water masses and circulation in the East Sea (Sea of Japan)

Recent findings on water masses, biogeochemical tracers, deep currents and basin-scale circulation in the East/Japan Sea, and numerical modeling of its circulation are reviewed. Warming continues up to 2007 despite an episode of bottom water formation in the winter of 2000–2001. Water masses have definitely changed since the 1970s and further changes are expected due to the continuation of warming. Accumulation of current data in deep waters of the East/Japan Sea reveals that the circulation in the East/Japan Sea is primarily cyclonic with sub-basin scale cyclonic and anticyclonic cells in the Ulleung Basin (Tsushima Basin). Our understanding of the circulation of intermediate water masses has been deepened through high-resolution numerical studies, and the implementation of data assimilation has had initial success. However, the East/Japan Sea is unique in terms of the fine vertical structures of physical and biogeochemical properties of cold water mass measured at the highest precision and their rapid change with the global warming, so that full understanding of the structures and their change requires in-depth process studies with continuous monitoring programs.     

北部湾盆地涠西南凹陷C洼烃源岩热史及成熟史模拟

北部湾盆地涠西南凹陷C洼流沙港组烃源岩热史及成熟史研究,对C洼深水油气勘探具有指导意义。在恢复涠西南凹陷C洼地史和热史的基础上,利用EASY%Ro模型计算了流沙港组烃源岩的成熟度史。研究结果表明,在涠西南凹陷发展的裂陷阶段初始期热流值较高,最大值约为77mW/m2,其后热流值逐渐减小,现今热流值约为54mW/m2;涠西南凹陷C洼流沙港组烃源岩开始生烃(Ro=0.5%)时间为51MaBP,达到生烃高峰(Ro=1%)时间为42MaBP,达到高成熟演化阶段(Ro=1.3%)时间为17MaBP;对比涠1井流沙港组烃源岩演化特征,处于C洼深水勘探区的流沙港组烃源岩成熟度较高,生烃能力较强,拥有广阔的油气勘探前景。     

南海西部断裂系研究及其物理模拟实验证据

南海西部断裂系是由四条典型的走滑断裂所组成的断裂系统,是南海扩张的西部边界.此断裂系主要是在白垩纪以来的印-藏碰撞、新生代印支挤出和南海扩张的共同作用下形成的.通过模拟实验,探讨此断裂系的成因、演化过程,认识到此断裂系经历了五期构造运动.     

端元分析模型在长江口邻近海域沉积物粒度数据反演方面的应用

海洋沉积物粒度分布曲线往往同时具有多个峰,而且同一类型沉积物因时间和空间上的不同其粒度分布曲线峰的位置也不同,沉积物粒度分布多峰的特点反映了沉积物不同的输运形式和沉降过程[1,2].因此,在沉积物的粒度分布数据中保存了有关沉积物输运和沉降的信息,而获得这些信息对于揭示沉积区域水动力特性、沉积物输运和沉降规律具有重要的意义.     

Formation and Movement of the ESIW as Modeled by MICOM

The presence of the minimum salinity and oxygen-rich East Sea Intermediate Water (ESIW) off Korean coast has raised many questions about its origin and movement. This study attempts to answer these questions in the context of numerical model. For this, the Miami Isopycnic Coordinate Ocean Model is used with surface and inflow boundary conditions based on available data. Model results show that the ESIW forms most distinctly off Vladivostok, where the center of doming structure is observed, and moves southward along Korean coast forming a large cyclonic gyre around the doming. The renewed ESIW has the character of minimum potential vorticity common to usual mode waters. These results are compatible with various indications made in previous observational and theoretical studies. However, it is not known whether the doming structure is a result of convection or the latter is favored by the former. This revised version was published online in August 2006 with corrections to the Cover Date.