... these responses within specific time and energy windows. The outputs of the algorithms represent key parameters that identify the atomic composition of the rock and its porous space. Four of these key parameters are the Neutron Capture Cross Section (Sigma), the Hydrogen Index (HI); the Carbon-Oxygen ratio (C/O...

...-Carboniferous sandstone. Relevant environmental corrections were applied to the data except for the formation water salinity correction. The hydrogen index values are obtained from the thermal neutron porosity measurement using corrections incorporating the measured sigma from the gamma ray spectroscopy tool...

.... In the simple case of two measurements, density and neutron, the measurement space reduces to the familiar density-neutron crossplot. The porosity space becomes the line joining the matrix point to the water point. Since gas has lower density and hydrogen index than water, any data point affected by gas...

... Upstream Oil & Gas water saturation hydrogen index wireline tool well logging pore psdf method hydrocarbon log analysis lwd distribution pore-size-dependent fluid substitution LWD tool fluid substitution porosity Symposium Magenta hydrocarbon phase permeability University...

... at the formation pressure and temperature is then used in a nuclear forward modeling program that converts the mixture composition and mixture density to nuclear parameters such as electron density ( e), hydrogen index (HI), and thermal neutron capture cross section The result is a program that can be used...

... have different densities and exhibit fast exchange in the magnetic resonance time scales, they cannot be separated nor their effective hydrogen index determined. Corrections to conventional methods based on the Langmuir isotherm can be applied, but this depends on laboratory investigations on cores...

... at any given depth, BL equal to the density when no TOC is present (seeing a pattern yet?) and finally level of maturity (LOM) which is the slope of S2 (from pyrolysis) and TOC. This is essentially the hydrogen index from pyrolysis (not neutron response). (Fig. 6) LOM can also be calculated from...

..., the additional 3rd detector enabled cased-hole porosity measurement sensitivity for rocks of 30% or higher hydrogen index (Jacobson 2013). The measurement dependence on formation salinity is also much reduced compared to the traditional thermal-neutron capture cross section (Sigma) analysis (Guo 2012...

... for estimating reservoir capacity and inferring saturating fluids. The neutron log, measuring hydrogen index (HI), is commonly expressed in apparent water-filled porosity units assuming a constant matrix lithology, whereby it is not always representative of actual pore volume. On the other hand, a lithology...

... into water (Sw) and hydrocarbon (Sh) was achieved using the Archie model, however sub- dividing Sh into Sg and So was more challenging and relied on the apparent changes in porosity as recorded by the neutron log. As gas moved through the reservoir, the hydrogen index [HI] of the fluids would change which...

... workflow log analysis dielectric dispersion hydrogen index Symposium heavy oil reservoir saturation heavy oil Schlumberger dielectric log Upstream Oil & Gas correspond application probability distribution reservoir University characterization SPWLA 53rd Annual Logging Symposium, June...

... developed new correlations, the coefficients of which depend on tool hardware, acquisition modes, and processing algorithms. These are demonstrated to be useful from 10 mPa-s to 1,000,000 mPa-s or more. We also introduce the partitioned hydrogen index method, which uses a porosity model and a new...

... displayed by default. The N/M porosity reads the closest to the hydrogen index in shales, but its standoff and holesize corrections are large. The M/F porosity requires the smallest standoff and holesize corrections, but reads the highest in shales. The N/F porosity is a reasonable compromise, reading...

... a pulsed neutron source include hydrogen index, formation capture cross section (sigma), formation density from neutron-induced gamma-rays (NGD* Neutron Gamma Density), and formation elemental composition from the capture spectra (capture spectroscopy). The latter is then used to derive lithology...

... index levels and high viscosities in the tar mats, compared to the hydrogen indexes and viscosities of the medium/light oil. Also, because of the hydrogen index, the total porosity values measured by NMR and density logs are very different in the tar mat levels, but they have good agreement...

... as the primary, log scale formation evaluation data set. As is well known in gas or light oil bearing intervals determination of porosity is complicated by the influence of the low hydrogen index and density of the fluid ? the ?gas effect?. Although this is a case study based upon results from a Niger Delta...

... sufficient insight into the nature of the fluid being pumped that a completely uncontaminated sample is not required to determine the reservoir fluid characteristics. Field and lab tests have shown that viscosity, gas-oil ratio, and hydrogen index can be determined from nuclear magnetic resonance (NMR...

...-laboratory signal-to-noise ratios and operat- ing speeds. At the same time, the resonance frequency is still close enough to that of wireline (MRIL®) 1 and LWD tools (MRIL-WDrM) 1 to provide exact hydrogen index values for porosity correction and to differentiate between filtrate and connate fluids...

... measurements consisting of concurrent 1-sec and 14-sec recovery time data are used to correct for hydrogen index and polarization effects in order to obtain a mineralogy-independent total porosity. The NMR measurements are also used to generate, through an automated NMR Time Domain Analysis (TDA), a direct...

..., the pressure- and temperature dependence of the hydrogen index (HI) of the reservoir fluid was determined from laboratory measurements for application to fluid volume calculations from wireline NMR data. The measurements show that dissolved gas has a strong impact on the NMR response of reservoir fluids...