A stochastic Bayesian approach for combining well logs and geophysical surveys for enhancing subsurface characterization is presented. The main challenge we face is in creating the bridge to link between ambiguously related geophysical surveys and well data. The second challenge is imposed by the disparity between the scale of the geophysical survey and the scale of the well logs. Our approach ...

Different methods of lithology predictions from geophysical data have been developed in the last 15 years. The geophysical logs used for predicting lithology are the conventional logs: sonic, neutron-neutron, gamma (total natural-gamma) and density (backscattered gamma-gamma). The prompt gamma neutron activation analysis (PGNAA) is another established geophysical logging technique for in situ e...

A combination of subsurface borehole imaging data and drilling logs were used to characterize the fractures and lithology in 40 bedrock wells at the fractured-rock research site in the Mirror Lake area in Grafton County, New Hampshire. The purpose of the research was to determine whether subsurface lithology and fractures have an effect on the hydraulic conductivity of the crystalline-rock aqui...

A Bayesian model coupled with a fuzzy neural network (BFNN) is developed to alleviate the difficulty of using geophysical data in lithology estimation when cross correlation between lithology and geophysical attributes is nonlinear. The prior estimate is inferred from borehole lithology measurements using indicator kriging based on spatial correlation, and the posterior estimate is obtained fro...

The purpose of this study is to construct a fuzzy lithology system from well logs to identify formation lithology of a groundwater aquifer system in order to better apply conventional well logging interpretation in hydro-geologic studies because well log responses of aquifers are sometimes different from those of conventional oil and gas reservoirs. The input variables for this system are the g...

Introduction: The shergottite meteorites have been subdivided into three groups based on texture and mineralogy [1]. EETA79001 is a shergottite that contains examples of all three lithologies: lherzolitic (lithology X), olivine-phyric (lithology A), and basaltic (lithology B). Therefore, studying the magmas involved in the petrogenesis of EETA79001 may provide information not only on its own pe...

In the south area of China, there covers thick soil and flourish vegetation on the top of the rocks, so there is little research on lithology analysis by remote sensing in the south area, and there is also no mature methods on this aspect. Three Gorges are the south area which is thickly covered by soil and flourish vegetation and the lithology analysis is very difficult. Three Gorges possess t...

Abstract. In this paper, we consider a multi-lithology diffusion model used in stratigraphic modelling to simulate large scale transport processes of sediments described as a mixture of L lithologies. This model is a simplified one for which the surficial fluxes are proportional to the slope of the topography and to a lithology fraction with unitary diffusion coefficients. The main unknowns of ...

Citation: Damodararao K, Singh SK, Rai VK, Ramaswamy V and Rao PS (2016) Lithology, Monsoon and Sea-Surface Current Control on Provenance, Dispersal and Deposition of Sediments over the Andaman Continental Shelf. Front. Mar. Sci. 3:118. doi: 10.3389/fmars.2016.00118 Lithology, Monsoon and Sea-Surface Current Control on Provenance, Dispersal and Deposition of Sediments over the Andaman Continent...

In this paper, a novel neural networks based lithology identification approach is proposed. First, the logging curves are squared so that the noise is filtered off. Second, consecutive segments representing similar stratums are merged so that the dimension of inputs is reduced. Third, data sampling from different logging curves are respectively normalized so that the curves of small magnitude a...