Integrating Wireline Logs and Seismic Data to Analyse The Facies snd Paleogeography of Tanjung Formation, Barito Basin, South Kalimantan

Author(s):  
E. A. Rosa

The study area is physiographically part of the Barito Basin, South Kalimantan (Van Bemmelen, 1949). 2D seismic data along with well logs from three wells, biostratigraphy data from two wells, and core data are utilized to do an integrated sequence stratigraphy. Petrography data from the equivalent formation at well-X from the study area is also used to support the evaluation. This study was to determine lithology facies and depositional environment based on several key maps: Sand Shale Ratio (SSR), Isopach, and Paleogeographic Maps. After that, seismically-supported sequence stratigraphy was applied to vertically and laterally subdivide the facies distribution and paleogeography into two depositional models based on the following key sequence-stratigraphic markers: (1) Sequence Boundary (SB)-1 to SB-2 that show regressive succession, and (2) SB-2 to Top Tanjung Formation that reflects transgressive phase.

2021 ◽  
Vol 11 (3) ◽  
pp. 1226
Author(s):  
Abd Al-Salam Al-Masgari ◽  
Mohamed Elsaadany ◽  
Abdul Halim Abdul Latiff ◽  
Maman Hermana ◽  
Umar Bin Hamzah ◽  
...  

This study focuses on the sequence stratigraphy and the dominated seismic facies in the Central Taranaki basin. Four regional seismic sequences namely SEQ4 to SEQ1 from bottom to top and four boundaries representing unconformities namely H4 to H1 from bottom to top have been traced based on the reflection terminations. This was validated using well logs information. An onlapping feature on the seismic section indicates a new perspective surface separated between the upper and lower Giant formation, which indicates a period of seawater encroachment. This study focused extensively on deposition units from SEQ4 to SEQ1. The seismic facies, isochron map, and depositional environment were determined, and the system tract was established. This study was also able to propose a new perspective sequence stratigraphy framework of the basin and probable hydrocarbon accumulations and from the general geological aspect, SA-Middle Giant Formation (SEQ3) could act as potential traps.


Author(s):  
Onyewuchi, Chinedu Vin ◽  
Minapuye, I. Odigi

Facies analysis and depositional environment identification of the Vin field was evaluated through the integration and comparison of results from wireline logs, core analysis, seismic data, ditch cutting samples and petrophysical parameters. Well log suites from 22 wells comprising gamma ray, resistivity, neutron, density, seismic data, and ditch cutting samples were obtained and analyzed. Prediction of depositional environment was made through the usage of wireline log shapes of facies combined with result from cores and ditch cuttings sample description. The aims of this study were to identify the facies and depositional environments of the D-3 reservoir sand in the Vin field. Two sets of correlations were made on the E-W trend to validate the reservoir top and base while the isopach map was used to establish the reservoir continuity. Facies analysis was carried out to identify the various depositional environments. The result showed that the reservoir is an elongate , four way dip closed roll over anticline associated with an E-W trending growth fault and contains two structural high separated by a saddle. The offshore bar unit is an elongate sand body with length: width ratio of >3:1 and is aligned parallel to the coast-line. Analysis of the gamma ray logs indicated that four log facies were recognized in all the wells used for the study. These include: Funnel-shaped (coarsening upward sequences), bell-shaped or fining upward sequences, the bow shape and irregular shape. Based on these categories of facies, the depositional environments were interpreted as deltaic distributaries, regressive barrier bars, reworked offshore bars and shallow marine. Analysis of the wireline logs and their core/ditch cuttings description has led to the conclusion that the reservoir sandstones of the Agbada Formation in the Vin field of the eastern Niger Delta is predominantly marine deltaic sequence, strongly influenced by clastic output from the Niger Delta. Deposition occurred in a variety of littoral and neritic environment ranging from barrier sand complex to fully marine outer shelf mudstones.


GeoArabia ◽  
1997 ◽  
Vol 2 (2) ◽  
pp. 179-202 ◽  
Author(s):  
Sabah K. Aziz ◽  
Mohamed M. Abd El-Sattar

ABSTRACT The Lower Cretaceous (Berriasian to Valanginian) Habshan Formation (Lower Thamama Group) of Abu Dhabi was deposited on a broad carbonate shelf. In east onshore Abu Dhabi, the Habshan Formation consists mainly of limestone and dolomite reaching a thickness of more than 1,100 feet. The depositional environment ranged from shallow-water peritidal to deeper shelf basin. The integration of seismic-stratigraphic, biostratigraphic, lithostratigraphic and electric log data reveals three sequences (I to III) and three shelf edges within the Habshan Formation in east onshore Abu Dhabi. These high energy shelfal sediments prograde toward the basin to the east and northeast with their shelf edges trending north-northwest to south-southeast. The seismic data indicates that the basin was filled in the east during the Hauterivian, after the deposition of Sequence IV (equivalent to the Zakum formation). Good reservoir development is found in the carbonates deposited in the high energy environment along the shelf edge of the Habshan sequence, particularly within the oblique and sigmoidal clinoforms, whereas potential source rocks are expected to be developed basinward. This combination renders the Habshan and Zakum sequences an attractive exploration target, both as structural and stratigraphic traps. Recent exploration activity in the area established the presence of hydrocarbons within the Habshan Sequence III in east onshore Abu Dhabi.


1995 ◽  
Vol 35 (1) ◽  
pp. 296
Author(s):  
J. S. Rasidi

The Late Cretaceous Withnell Formation has attracted very little exploration attention because of the perception that it has poor hydrocarbon potential. This unfavourable perception has arisen from the fact that very little is known about its depositional environment and lithofacies and therefore, its petroleum prospectivity.A sudden fall of relative sea level occurred at the end of the Santonian, and was followed by the deposition of the siliciclastic Withnell Formation. The occurrence of a number of channels and canyons at the base of the formation, over the old shelf and slope on the southern margin of the sub-basin, supports the hypothesis that the Withnell Formation began as a lowstand systems tract. The thickness distribution of the formation and the progradation direction of seismic packages suggest a southeasterly provenance. Correlation of seismic data and well logs, and rock descriptions demonstrate the presence of units deposited during increasing water depths and subsequent highstand systems tract.Much more information, both seismic and well data, is required to establish the facies distribution within the Withnell Formation which may contain sand-prone lowstand facies such as basinfloor or slope fans. The presence of such reservoir facies would enhance the petroleum prospectivity of the Withnell Formation.


1994 ◽  
Vol 34 (1) ◽  
pp. 350 ◽  
Author(s):  
Keyu Liu ◽  
Lincoln Paterson ◽  
Feng Xu Jian

SEDPAK is a forward modelling computer program for depositional processes developed by the University of South Carolina's StratMod Group. It simulates the geometry of generalised lithofacies in a sedimentary sequence or a basin by considering principally four major geological variables: eustatic sea level, tectonic movement, sediment accumulation, and initial and evolving basin surfaces.Based on seismic data, well logs and other information from drill holes, the geometries of sedimentary sequences of the Gippsland Basin and the Barrow-Exmouth Sub-basins have been successfully reproduced on both basin and reservoir scales using SEDPAK 3.12. The simulation results indicate that eustacy, tectonics, sediment input and basin physiography can be equally important in controlling the geometry of strata and basin architecture. However, some differences exist: (1) tectonic movement normally contributes to long-term variations of the first order (megasequence) basin architecture and configuration; (2) the second order (sequence) basin architecture and stratal geometry can be controlled by either sediment supply, eustacy, tectonism or a combination; and (3) high frequency facies variations and stratal geometry within individual sequences are primarily controlled by eustatic sea level variations and basin physiography.This study has demonstrated that SEDPAK is a useful tool for reconstruction of basin evolution histories and for reservoir characterisation. It can also be used to predict sedimentary facies in undrilled exploration frontier areas. In addition, it can be used to address some critical assumptions and problems in the sequence stratigraphy concept. SEDPAK is particularly useful in the study of high frequency sequence stratigraphy and cyclicity, where various sequence or parasequence bounding surfaces and internal geometry can not be easily recognised from seismic data, well logs and outcrops.


2021 ◽  
Vol 19 (3) ◽  
pp. 63-82
Author(s):  
S. Inichinbia ◽  
Halidu Hamza

The sequence stratigraphy of Amangi field of the Niger Delta was studied using seismic data and well logs. The field is a structurally  complex one and presents serious challenges to hydrocarbon exploration and production. The main objective of these analyses is to  identify sand intervals using the available data. Well log data were used as additional tools to constrain the seismic correlations in order to solve the correlation problem. The well logs were evaluated for the field’s petrophysical properties by combining the gamma ray and resistivity logs to determine reservoir zones with considerable hydrocarbon saturation. Also, the relationship between some basic rock properties/attributes and litho-types were determined for the study area. Next, well-to-seismic ties were produced and two horizons were picked. Acoustic impedance inversion was also performed which revealed “hard sands” due to mixed lithologies (heterolithics). This made it difficult to discriminate the sands from shales in the P-impedance domain alone. So, progress was made to determine the net-to-gross of the field. The analysis revealed that these reservoirs have shaly sand with shale content of 10%, porosity averaging 21%, and hydrocarbon saturation of 90%. The result established a vertical stack of a series of reservoirs in an anticlinal structure of which the H1000 and H4000 stand out for their huge volumes of rich gas condensate accumulation. This discovery provoked the drive for the first phase of development of this field. Keywords: stratigraphy, facies, net-to-gross, horizon, lithology, well-to-seismic tie, impedance


2019 ◽  
Vol 45 (2) ◽  
pp. 209-216
Author(s):  
Afroza Parvin ◽  
ASM Woobaidullah

The application of sequence stratigraphy to resolve the miscorrelation between different genetic units in reservoir characterization in a gas field of Surma Basin is dealt with. Interpretation of available seismic and wireline logs (gamma ray, resistivity, density and neutron porosity) give the sequence stratigraphic correlation of reservoir sands. The reservoirs geometry, its extent, seal architecture and trapping styles have been revealed better with this correlation. There is juxtaposition of two reservoir sands, namely A1 and A2. A1 is located at older highstand sand, whereas A2 is in the younger lowstand sand. Lithostratigraphically they might be same but sequences stratigraphy reveals that they are different and deposited at different times. Moreover, the concept reveals that lowstand sand has better reservoir quality than any highstand and transgressive sand. Asiat. Soc. Bangladesh, Sci. 45(2): 209-216, December 2019


2013 ◽  
Vol 734-737 ◽  
pp. 166-169
Author(s):  
Hong Qi Yuan ◽  
Ying Hua Yu ◽  
Dong Li Sun

Sequence is a relatively conformable succession of genetically related strata bounded by unconformities or their correlative conformities. The correct identification of sequence boundaries is the key to the success of the sequence stratigraphic approach. Stratigraphic boundaries provide the fundamental framework for the genetic interpretation of any sedimentary succession, irrespective of how one may choose to name the packages of strata between them. Sequence stratigraphy of main research content is mainly chronohorizon (unconformity or conformity) identification, and to determine its causes and characteristics. Then, the key to sequence stratigraphy is identification unconformity and their correlative conformities. Unconformity and their correlative conformities on the seismic profiles, well logs, lithology, paleontology, and geochemical data have distinctive sequence boundaries mark characteristics.


Sign in / Sign up

Export Citation Format

Share Document