Based on the Markov model and the basic theory of information entropy, this paper puts forward a new method for optimizing the location of observation points in order to obtain more information from limited geological investigation. According to the existing data from observation points data, classification of tunnel geological lithology was performed, and various lithology distribution were de...

The cross plotting of rock properties for fluid and lithology discrimination was carried out in a Niger Delta oil field using well data from a given oil field. The data used for the analysis consist of suites of six wells. The reservoir was evaluated using gamma ray logs, volume of shale, resistivity and neutron porosity for well-02 and well-06. Sand lithology showed low gamma ray, high resisti...

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . LOCATION AND PURPOSE OF STUDY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....

We conducted an integrated geomechanics case study of the Woodford shale to understand the effectiveness of multi-stage hydraulic fracturing. The study involves two parallel horizontal wells, each about 5,000 feet long with ~15 frac stages. Analysis of Instantaneous Shut-In Pressure (ISIP) of each frac stage indicates significant variations of the minimum horizontal principal stress (Shmin) mag...

Subsurface microbial community structure in relation to geochemical gradients and lithology was investigated using a combination of molecular phylogenetic and geochemical analyses. Discreet groundwater and substratum samples were obtained from depths ranging from 182 to 190 m beneath the surface at approximately 10-cm intervals using a multilevel sampler (MLS) that straddled Cretaceous shale an...

Characterisation of the heterogeneous naturally fractured reservoirs is an essential and significantly challenging task, especially due to the limited data availability. This paper presents a foundation relationship between P-wave / S-wave velocity and formation resistivity for improved fracture characterisation. Rock matrix and fluid volumetrics are combined with the basic correspondence betwe...

The interaction between human activities and watershed geology is accelerating long-term changes in the carbon cycle of rivers. We evaluated changes in bicarbonate alkalinity, a product of chemical weathering, and tested for long-term trends at 97 sites in the eastern United States draining over 260,000 km(2). We observed statistically significant increasing trends in alkalinity at 62 of the 97...

The sand intervals of the Lower Goru Formation of the Cretaceous age, widely distributed in the Middle and Lower Indus Basin of Pakistan, are proven reservoirs. However, in the Sawan gas field of the Middle Indus Basin, these sandstone intervals are very deep and extremely heterogeneous in character, which makes it difficult to discriminate lithologies and fluid saturation. Based on petrophysic...

High slope simulation analysis is an essential means of engineering design, construction, and operation management. It necessary to master dynamics, ensure safety, analyze instability mechanisms, carry out stability early warning prediction. This paper, aiming at the landslide phenomenon high on left bank a reservoir project, considering influence stratum lithology, fault, excavation unloading,...

Observations from 145 submersible dives are used to create a database of mid-ocean ridge scarp topography and lithology. Seafloor lithologies are classified into extrusives, basaltic talus, dykes, gabbros and serpentinites, and the dive locations are broadly classified according to whether they are close to transform valleys and as a function of ridge spreading rate. The database is used to det...