Basic well log analysis

Asquith, George B.; Krygowski, Daniel; Henderson, Steven; Hurley, Neil

doi:10.1306/mth16823

Cited by 356 publications

(292 citation statements)

References 0 publications

Supporting

Mentioning

285

Contrasting

Unclassified

Order By: Relevance

“…Secondly, porosity as one of the factors that might affect the responses of the logs, can be derived from sonic log as an acoustic log and in some cases with resistivity log. Both logs show similar signature when passing via a brine saturated permeable formation [16]. However, the presence of gas in this type of formation will cause the curve to deflect from the norm.…”

Section: Basic Principlesmentioning

confidence: 94%

See 1 more Smart Citation

Generating Pseudo-Synthetic Seismogram with Resistivity Logs Considering the Effect of Gas: Application to Bizzy Field, Onshore, Niger-Delta, Nigeria

Kafisanwo¹,

Abe²,

Falade³

2019

EESRJ

View full text Add to dashboard Cite

Traditionally, sonic and density logs are vital components during the generation of synthetic seismogram. However, sonic logs as observed in many studies, often have poor quality or even absent in some cases. This work is a case study for the transformation of resistivity logs to pseudo sonic logs for the generation of pseudo synthetic seismogram considering the effect of gas. This research studies the relationship between resistivity and sonic logs in order to utilize the former for the generation of pseudo synthetics when sonic log is absent or poor. Standard synthetic seismograms were first created conventionally using sonic and density logs as inputs. The sonic log values were then plotted against the corresponding resistivity values for each well to derive their relationship using both linear and polynomial functions. Generally, the crossplot shows a fair correlation but some scattered plots were observed. Further probe into these observed anomalies revealed the areas to be gas saturated. A better correlation was achieved within affected zones by doing independent crossplots for previously gas delineated units. The standard synthetic generated were used as control for the pseudo synthetics and better correlation is observed when compared with the previous pseudo synthetics that does not acknowledge gas-effect.

show abstract

Section: Basic Principlesmentioning

confidence: 94%

“…It is recommended to always run a caliper log to compliment density log interpretation. Also, Asquith [16] in his study proposed that any density value whose correction exceeds 0.20g/cc should be tagged as invalid.…”

Section: Basic Principlesmentioning

confidence: 99%

Generating Pseudo-Synthetic Seismogram with Resistivity Logs Considering the Effect of Gas: Application to Bizzy Field, Onshore, Niger-Delta, Nigeria

Kafisanwo¹,

Abe²,

Falade³

2019

EESRJ

View full text Add to dashboard Cite

show abstract

“…where K is the permeability in mD, φ is Effective porosity in v/v and wir S is the irreducible water saturation in v/v. In this study the permeability was estimated first by using the calculated water saturation, and then the results were compared with those estimated from Crain's method [22] using irreducible wa- A reservoir at irreducible water saturation exhibits BVW values that are constant throughout but if the BVW is not constant means that the reservoir or zone is not at irreducible water saturation [16].…”

Section: Permeability Estimationmentioning

confidence: 99%

Petrophysical Analysis of Reservoirs Rocks at Mchungwa Well in Block 7 Offshore, Tanzania: Geological Implication on the Reservoir Quality

Mjili¹,

Mulibo²

2018

OJG

View full text Add to dashboard Cite

The present work highlights the results of the study conducted to estimate the petrophyiscal properties of the Mchungwa well with the aim of assessing the quality of reservoirs rocks. A set of well logs data from Mchungwa well were used for the analysis that involved identification of lithology, hydrocarbon and non-hydrocarbon zones and determinations of petrophysical parameters such as shale volume, porosity, permeability, fluid saturation and net pay thickness. This study was able to mark six sandstone zones with their tops and bases. Of the six zones hydrocarbon indication was observed on four zones from which estimation of petrophysical parameters was done to assess the reservoirs quality. The petrophysical parameters across the four reservoirs yield an average shale volume ranging from 0.08 to 0.15 v/v. The porosity ranges from 7% to 23%, indicating a fair to good porosity sandstone, while permeability ranges from 0.01 to 6 mD. The porosity and permeability results suggest that the quality of the sandstone reservoirs identified at Mchungwa well is poor. Fluid types defined in the reservoirs on the basis of neutron-density log signatures and resistivity indicate a mixture of water and gas. However, high water saturation (50% -100%) indicates that the proportion of void spaces occupied by water is high, thus, indicating low hydrocarbon saturation of 2.4%, 17.9%, 19.2% and 39.3%. Generally the results show that hydrocarbon potentiality at Mchungwa well is extremely low because of small net pay thickness and very low hydrocarbon saturation. This could be attributed to the geology of the surrounding area where low hydrocarbon saturation suggest the presence of non-commercial volumes of either migrant gas or gas generated from the interbedded claystone sediments, which are dominant in the observed well.

show abstract

“…The equations and parameters are used in this procedure (Fig.2) proposed by [4], [5], [6], [7], [8], [9], [10], [11] and [12].…”

Section: Radioactive (Gamma Ray Density Neutron)mentioning

confidence: 99%

Well Log Sequence Stratigraphy and the Pertophysical Properties of the Shiranish Formation in the Kirkuk Oil Field (K-260 and K-229)

Al-Zaidy¹

2017

djps

View full text Add to dashboard Cite

The Shiranish Formation comprises the globigerinal marls and limestones of the Upper Senonian (Upper Campanian-Maestrichtian). The present study has been discussed the pertophysical properties of this marly rocks in Kirkuk oil field (K-260 and K-229). The study area is located in northeastern Iraq (Kirkuk areas). This area lies within the Zagros foreland basin, bordered on the northeast by the Zagros Mountains and on the southeast by the Arabian Shield, and consists of linear and high amplitude folds that trend in a northwest-southeast direction. The Shiranish Formation was deposited during the transgression period after the sea level fall marked by the glauconitic contact (SBI) with the Kometan Formation. According to the general facies observation with the gamma ray and resistivity logs patterns, there are two major units in this Formation. The first unit is represented by six cycles of transgressive system tracts (TST) which bounded the upper unit by maximum flooding surface; the second unit is represented by three cycles of high system tracts which unconformably underlying of Aaliji Formation. According to the porosity type and the conductivity properties in addition to decreasing and increasing of shale effect (Gamma Ray) for the Shiranish Formation within K-260 and K-229 there are five petrophysical zones. These zones may be divided in to two Groups:-A. Low petrophysical properties rocks, this include the zones II and IV. B. Good petrophysical properties rocks, this include the zones I, III and V.The zones of group B are important rock units because there are shows of fractured porosity and gas effects in the zones three and five. Where, the zone three is represents a gas effect when the neutron and density porosity are extrusive. While the zone five are represent the fractured porosity in addition to present of gas effects. The first zone is different from the previous two types by the type of rock is limestone and the fabric/porous type is moldic and intragranular grainstone. At the last of this study the researcher is suggested that the Shiranish Formation may be a good reservoir rocks (fractured reservoir).

show abstract

Basic well log analysis

Cited by 356 publications

References 0 publications

Generating Pseudo-Synthetic Seismogram with Resistivity Logs Considering the Effect of Gas: Application to Bizzy Field, Onshore, Niger-Delta, Nigeria

Generating Pseudo-Synthetic Seismogram with Resistivity Logs Considering the Effect of Gas: Application to Bizzy Field, Onshore, Niger-Delta, Nigeria

Petrophysical Analysis of Reservoirs Rocks at Mchungwa Well in Block 7 Offshore, Tanzania: Geological Implication on the Reservoir Quality

Well Log Sequence Stratigraphy and the Pertophysical Properties of the Shiranish Formation in the Kirkuk Oil Field (K-260 and K-229)

Contact Info

Product

Resources

About