scholarly journals Biostratigraphy and Facies Analysis of Upper Valanginian-Upper Hauterivian (Sarmord Formation) in Maten Anticline, Northern Iraq

2021 ◽  
Vol 54 (2F) ◽  
pp. 1-12
Author(s):  
Mohammed Al-Abbasi ◽  
Majid Al-Mutwali ◽  
Nabil Al-Banna
Keyword(s):  
Green Algae ◽  
Tidal Flat ◽  
Facies Analysis ◽  
Depositional Environments ◽  
Marine Environments ◽  
Northern Iraq ◽  
Upper Hauterivian ◽  
Assemblage Zone ◽  
Characteristic Features ◽  
Marly Limestone

Biostratigraphical and sedimentological study of the Sarmord Formation (Upper Valanginian - Upper Hauterivian) at the southern limb of Maten anticline is conducted within a well-exposed section. The formation is composed of marl, marly limestone, limestone, and dolostone, which yielded moderately diversified benthonic foraminiferal fauna, green algae, echinoderms, gastropods and some bioclast. The stratigraphic distribution of the benthonic species permits the recognition of two well-defined biozones. These are Everticyclammina kelleri Assemblage Zone, which represents the Late Valanginian age and Pseudocyclammina lituus Assemblage Zone, indicating Hauterivian age. These larger benthonic foraminiferal biozones are correlated with other zonal schemes inside and outside of Iraq, which indicates that the age of the Sarmord Formation in Maten anticline extends from Late Valanginian to Late Hauterivian age. The Sarmord Formation in the studied section is composed of limestone, dolomite, marl and conglomerate lithofacies types. Limestone lithofacies is represented by lime wackestone microfacies. According to the characteristic features of these facies, the depositional environments extend from tidal flat to shallow open marine environments.

scholarly journals Microfacies and Palaeoenvironment of Avanah Formation (Middle Eocene) Geli Bessri in Dohuk City / North of Iraq

2020 ◽  
Vol 25 (1) ◽  
pp. 85
Author(s):  
Mustafa A. Abdullah ◽  
Faris N. Hassan ◽  
Abdulsalam. M.Saleh
Keyword(s):  
Benthic Foraminifera ◽  
Depositional Environment ◽  
Facies Analysis ◽  
Middle Eocene ◽  
Depositional Environments ◽  
Thin Layers ◽  
Marine Platform ◽  
Marly Limestone

This research is based on (23) Samples selected from the Avanah Formation (Middle Eocene) in the Geli Bessri section in Dohuk to recognize the microfacies and depositional environments. The Avanah Formation consists of rocks of marly limestone and limestone containing Alveolina and thin layers of sandstone lithofacies found in the lower part of the Formation. The depositional environment was determined depending on skeletal and non- skeletal grains. The facies of the Avanah Formation were divided into four main microfacies and four submicrofacies based on skeletal and non- skeletal grains: The mudstone and wackestone, which is divided into benthic foraminifera wackestone and Rotaliids wackestone, the Formation also contains the packstone which is divided into the Rotaliid - Miliolid Lime packstone submicrofacies and benthic foraminifera lim packstone submicrofacies, in addition to the lime grainstone and also contains the Sandstone lithofacies located at the bottom of the Formation. The Avanah Formation in the middle and upper part is subjected to diagenesis process early dolomization and it is observed this through floating dolomite rohmb. According to the results of the facies analysis and the presence of foraminifera fossils, the Formation was deposited in open marine platform to restricted platform interior.   http://dx.doi.org/10.25130/tjps.25.2020.014  

POSSIBLE MULTICELLULAR GREEN ALGAE IN EARLY TONIAN MARINE ENVIRONMENTS

2020 ◽  
Author(s):  
Katie Maloney ◽  
◽  
Galen Halverson ◽  
James Schiffbauer ◽  
Shuhai Xiao ◽  
...  
Keyword(s):  
Green Algae ◽  
Marine Environments

scholarly journals Facies Analysis and Depositoinal Environment of D-3 Reservoir Sands Vin Field, Eastern Niger Delta

2019 ◽  
pp. 1-19
Author(s):  
Onyewuchi, Chinedu Vin ◽  
Minapuye, I. Odigi
Keyword(s):  
Seismic Data ◽  
Niger Delta ◽  
Depositional Environment ◽  
Gamma Ray ◽  
Facies Analysis ◽  
Depositional Environments ◽  
Width Ratio ◽  
Neutron Density ◽  
Wireline Logs ◽  
Isopach Map

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.

scholarly journals Three-Dimensional Modeling and Fluid Flow Simulation for the Quantitative Description of Permeability Anisotropy in Tidal Flat Carbonate

Energies ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 5557
Author(s):  
Hassan A. Eltom ◽  
Nabil A. Saraih ◽  
Oliver G. Esteva ◽  
Lundi Kusuma ◽  
Saleh Ahmed ◽  
...  
Keyword(s):  
Fluid Flow ◽  
Tidal Flat ◽  
Three Dimensional ◽  
Flow Simulation ◽  
3D Models ◽  
Depositional Environments ◽  
High Permeability ◽  
Stratigraphic Framework ◽  
Permeability Anisotropy ◽  
Lithofacies Association

Three-dimensional (3D) facies and petrophysical models were generated from previously published data of carbonate strata in the Dam Formation (eastern Saudi Arabia) to quantitatively investigate, describe, understand, model, and predict the permeability anisotropy in tidal flat carbonate on the basis of a sequence stratigraphic framework. The resulting 3D models were used to conduct fluid flow simulations to demonstrate how permeability anisotropy influences the production of hydrocarbons and ultimately affects decisions concerning future drilling in the exploration and development of carbonate reservoirs with tidal flat strata. The constructed 3D facies model consists of four lithofacies associations, two of which are grain-dominated associations and two of which are mud-dominated associations. These lithofacies associations vary spatially in four reservoir zones (zones 1 to 4), which represent two fourth-order sequences in the uppermost part of the Dam Formation. Zones 1 and 3 consist of transgressive parasequences, and zones 2 and 4 consist of the regressive parasequences of these sequences. The 3D porosity and permeability models have a coherent match with the distribution of the lithofacies and the stratigraphic framework of the Dam Formation. The results suggest that the permeability anisotropy in zones 1 and 3 is controlled by the occurrence of the grain-dominated lithofacies associated with tidal flat channels. This lithofacies association overlies the sequence boundaries of sequences 1 and 3, forms reservoir bodies with relatively high permeability values, and is elongated perpendicular to the shoreline of the depositional environment. In contrast, permeability anisotropy in zones 2 and 4 is thought to be controlled by the occurrence of the grain-dominated lithofacies associated with the oolitic shoal. This lithofacies association overlies the maximum flooding surface of sequences 2 and 4, forms reservoir bodies with relatively high permeability values, and is elongated parallel to the shoreline of the depositional environments. Fluid flow simulation results suggest that the trend in hydrocarbon production from the constructed 3D models depends on permeability anisotropy in each reservoir zone. Thus, recognizing trends in permeability anisotropy, which can be predicted using sequence stratigraphy, could help to identify potential areas for future drilling.

On some Paleocene invertebrates from the Potrerillos Formation (Difunta Group), northeastern Mexico

1995 ◽  
Vol 69 (5) ◽  
pp. 862-869 ◽  
Author(s):  
Francisco J. Vega ◽  
Maria Del Carmen Perrilliat
Keyword(s):  
Tidal Flat ◽  
Sedimentary Basins ◽  
Depositional Environments ◽  
Northeastern Mexico ◽  
Potrerillos Formation ◽  
First Time

Three species of mollusks and one annelid are described from the Paleocene upper mudstone member of the Potrerillos Formation (La Popa Basin), and from the upper part of the Rancho Nuevo Formation (Parras Basin). The species described include a gastropod, a bivalve, a nautiloid and a serpulid worm, which are formally reported for first time as Paleocene fauna of the Difunta Group in northeastern Mexico. The nautiloid species provides the basis for correlation between the two sedimentary basins of the Difunta Group, as it is reported for Paleocene layers of the two formations studied. Shoreface and tidal-flat depositional environments are inferred for the Paleocene rocks of the Difunta Group.

Facies analysis and depositional environment of the Geli Khana Formation (Middle Triassic), Northern Iraq

2014 ◽  
Vol 8 (7) ◽  
pp. 4765-4777 ◽  
Author(s):  
Ali Ismail Al-Juboury ◽  
Mohammed A. Al-Haj ◽  
Wrya Jihad Jabbar
Keyword(s):  
Depositional Environment ◽  
Middle Triassic ◽  
Facies Analysis ◽  
Northern Iraq

Phytoplankton from the Lower Cambrian Læså formation on Bornholm, Denmark: biostratigraphy and palaeoenvironmental constraints

1992 ◽  
Vol 129 (1) ◽  
pp. 17-40 ◽  
Author(s):  
Małgorzata Moczydłowska ◽  
Gonzalo Vidal
Keyword(s):  
Lower Cambrian ◽  
Radioactive Decay ◽  
Depositional Environments ◽  
Event Correlation ◽  
East European ◽  
Depositional Settings ◽  
Assemblage Zone ◽  
Early Palaeozoic ◽  
A Minor ◽  
Bodies Of Water

AbstractAcritarchs from the Lower Cambrian Læsså formation on Bornholm, Denmark, are taxonomically diverse. Their state of preservation, including thermal, mechanical and chemical alteration, is discussed. Different states of thermal maturation of acritarchs in shales and phosphorites of the Broens Odde member could be explained in terms of possible irradiation from natural radioactive decay. The microfossils form two age-diagnostic assemblages that allow recognition of the Skiagia ornata–Fimbriaglomerella membranacea and Heliosphaeridium dissimilare–Skiagia ciliosa Assemblage Zones within the Broens Odde member of the Laeså formation. Acritarch-based biostratigraphy indicates that the Lower Cambrian Balka Formation and Læså formation correspond to the Schmidliellus mickwitzi Zone and Holmia kjerulfi Assemblage Zone recognized in Baltoscandia and the East European Platform. Acritarch distribution within three different depositional settings indicates that comparable spectra of morphotypes occurred in different depositional environments. This suggests the absence of facies control. During early Cambrian times palaeoenvironmental barriers in shallow, epicontinental shelf basins constituted a minor obstacle for widespread distribution of acritarch taxa. Formerly proposed early Palaeozoic acritarch provincialism appears insufficiently documented in the fossil record and no evidence could be extracted from the Cambrian record. Following a rapid radiation at the onset of the Phanerozoic, Cambrian phytoplankton populations underwent dispersion following oxygenic and nutrient-rich bodies of water within epicontinental and presumably basinal environments. Lower Cambrian acritarch taxa were largely cosmopolitan and little affected by lithofacies associations. A continuous flow of data is contributing to the emergence of acritarch-based biostratigraphy. Its apparent consistency suggests great usefulness for interregional and detailed event correlation.

Sign in / Sign up

Export Citation Format

Share Document