Global investigation of martian sedimentary fan features: Using stratigraphic analysis to study depositional environment

ATP 299P(2) is located in the south-west Queensland portion of the Jurassic Cretaceous Eromanga Basin. Exploration drilling within the permit has resulted in the discovery of several oil pools which are stratigraphically controlled. Appraisal drilling at the Talgeberry Oilfield demonstrated this point when Talgeberry-2, drilled at a structurally higher location, failed to encounter either of the producing sands in Talgeberry-1. Oil is currently being produced from the Wyandra Sandstone and Birkhead Formation in Talgeberry-1 and from the Murta Member in Talgeberry-2.Depositional models are presented for each of the producing reservoirs at the Talgeberry Field, based upon dipmeter interpretation. An integrated seismic stratigraphic study was also undertaken on the Birkhead Formation reservoir.Oil production at Talgeberry is currently confined to distributary channel sands or near-shore distributary mouth bar sands. Distal facies of the distributary mouth bar have been intersected and, while containing oil, have been found to be generally tight.Dipmeter interpretation has proven valuable in determining depositional environment but is limited in defining the a real extent of the reservoir. Seismic-stratigraphic studies are able to define the reservoir geometry better and lead to a more comprehensive understanding of the depositonal environment.

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STUDYING IN THE PAXOS ZONE THE CARBONATE DEPOSITIONAL ENVIRONMENT CHANGES DURING UPPER CRETACEOUS, IN SAMI AREA OF KEFALLINIA ISLAND, GREECE

Bulletin of the Geological Society of Greece ◽

10.12681/bgsg.11245 ◽

2017 ◽

Vol 43 (2) ◽

pp. 793

Author(s):

E. Zoumpoulis ◽

F. Pomoni-Papaioannou ◽

A. Zelilidis

Keyword(s):

Depositional Environment ◽

Upper Cretaceous ◽

Carbonate Platform ◽

Upward Trend ◽

Shallow Marine ◽

Sedimentary Environments ◽

Stratigraphic Analysis ◽

Marine Carbonate ◽

Carbonate Sequence ◽

Shallow Subtidal

The shallow-marine carbonate sequence of Sami (Kefallinia isl. Fig. 1) is a part of the Upper Cretaceous carbonate platform of the Paxi zone. Detailed lithostratigraphic and microfacies analysis of that sequence revealed clear periodicities and cyclicity. The high-resolution stratigraphic analysis has shown a number of lithofacies organized in groups (lithofacies associations), suggesting, on the whole, sedimentary environments ranging from lagoonal to peritidal context. The vertical arrangement of these lithofacies allowed the identification of a cyclic recurrence of the depositional and early diagenetic features, including a meteoric overprint on top of the elementary cycles. The cycles exhibit a shallowing upward trend from shallow subtidal to inter-supratidal and hypersaline facies, in a warm shallow marine environment.

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Interpretation of Depositional Environment of Rho Field Using Sequence Stratigraphic Analysis, Shallow Offshore Depobelt, Niger Delta

Journal of Scientific Research and Reports ◽

10.9734/jsrr/2020/v26i130217 ◽

2020 ◽

pp. 93-103

Author(s):

Okoli Emeka Austin ◽

Acra Jones Edward ◽

Ehirim Chukwuemeka Ngozi

Keyword(s):

Niger Delta ◽

Depositional Environment ◽

High Energy ◽

Delta Front ◽

Fluvial Systems ◽

Sequence Stratigraphic ◽

Stratigraphic Analysis ◽

Correct Orientation ◽

Stacking Pattern ◽

Input Reconstruction

Candidate Maximum Flooding Surfaces (MFS) identified on Rho-1, Rho-2 and Rho-3 were the basis of correlation across the wells for sequence Stratigraphic analysis in the field. Three (3) candidate MFS which include MFS-1, MFS-2 and MFS-3 were identified using the method adopted by Okoli [1]. Erosional surfaces were also delineated in wells from the observed stacking pattern between a sequence from Galloway model (1989) leading to the correlation of SB-1 and SB-2 across the wells. Using the Galloway model, four (4) depositional sequences were inferred SEQ (1-4). In the first sequence (SEQ 1), deposition occurred in a transgressive episode. Depositional environment was interpreted from electrofacies and revealing stacked sequences of reservoirs predominantly composed of fluvial channels which incised the Upper and Lower Shorefaces on a delta front system. In SEQ 2, looking at the aggradational pattern of the sequence, the formed channels were under the influence of both tidal and fluvial systems. In SEQ 3 and 4, based on electro-facies, the stacked reservoir sands were deposited predominantly in a shoreface/delta front environment and channel incisions in a wave subjugated high energy deltaic setting. The entire well section showed deposition in a regressive phase. Proposed conceptual models were generated using Petrel software and could be used as an input reconstruction of subsurface geological models. Indicating correct orientation of geo-bodies and facies belts (pinch outs of sands and shales), depositional dips and gross permeability architecture.

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Investigation on Metal Adornments From Ancient Eastern Europe

Frontiers in Materials ◽

10.3389/fmats.2020.600913 ◽

2020 ◽

Vol 7 ◽

Author(s):

Luminița Ghervase ◽

Monica Dinu ◽

Corina Borș ◽

Laurenţiu-Marian Angheluță ◽

Roxana Rădvan ◽

...

Keyword(s):

Iron Age ◽

Depositional Environment ◽

Archaeological Site ◽

Raw Material ◽

Soil Conditions ◽

Original Material ◽

Danube Basin ◽

Stratigraphic Analysis ◽

Good State ◽

Ceramic Vessel

This study focuses on the investigation of certain bronze adornment objects from the First Iron Age (the so-called middle Hallstatt period), dating to the ninth–eighth c. BC. These objects are part of a bronze and iron hoard (labeled Cx 116) discovered in the present Romanian territory, at Tărtăria–Podu Tărtăriei vest archaeological site, in Alba County. Along with a second hoard of bronze and iron objects, this represents a unique discovery for the present Romanian territory, namely, for the inner Carpathian area and the Lower and Middle Danube Basin, where no such votive discovery had been made by archaeological excavations. The objects, approximately 450 bronze and iron objects—weapons, tools, adornments, and harnesses—were found in the two hoards, in the Southern ditch, which outlines the archaeological site. Digital radiography has been used to assess the physical state of the objects and to identify potential specific craftsmanship details. It showed a fairly good preservation status, with incipient corrosion processes located in the core of some of the objects and some specific traces of the crafting process and subsequent mechanical defects were highlighted. The relatively good state of preservation of the objects can result from the fact that they had been protected from the humid environment by the ceramic vessel they were placed in. XRF and LIBS were used to identify the materials and to stratigraphically evaluate the objects. XRF scanned the surface of the objects, revealing elements related to both the raw material—a copper alloy with tin and lead, together with trace elements related to the specific mining location of the ores, and the depositional environment of the objects–such as iron. LIBS allowed a more in-depth stratigraphic analysis, which indicated a higher copper ratio—compared to iron—as the kinetic series advance, fact that sustains the idea that the major iron input was coming from the depositional environment. Both XRF and LIBS results were consistent with high elemental variability, probably due to the nature of the original material and the influence of the deposition soil conditions.

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Delineating Depositional Environment through Lithostratigraphy and 2D Sequence Stratigraphy of a Typical Ramp Succession: In the Obom Field Niger Delta

10.2118/207171-ms ◽

2021 ◽

Author(s):

Onome Okobiebi ◽

Becky Okobiebi

Keyword(s):

Sequence Stratigraphy ◽

Niger Delta ◽

Depositional Environment ◽

Facies Analysis ◽

Seismic Analysis ◽

3D Modelling ◽

Sequence Stratigraphic ◽

Stratigraphic Analysis ◽

Depositional Patterns ◽

Stacking Patterns

Abstract Modelling the most appropriate depositional environment is essential in the reservoir characterisation and 3D modelling of oil bearing sands and the integration of various workflows reduces the uncertainty in deciding the appropriate depositional model which serves as a precursor into petrophysical property distribution during 3D modelling. This paper elaborates a robust study of the integration facies analysis, 2D sequence Stratigraphy and biostratigraphy data in depicting the environment of deposition of the OBOM field. The lithological description of the G8 to the F5 reservoirs ranged from finning upward sequence and blocky shaped sequence as channel sands and coursing upward shoreface deposits. Mineralogical descriptions of the penetrated sands were also carried out, especially on the F5 reservoir in which the presence of radioactive minerals was decisive to constrain the depositional environment to lower shoreface. In the Sequence stratigraphic analysis two 3rd Order depositional cycles was identified from top to bottom in the field. This is substantiated by the facies trend, facies cross plot and cycles indicators like maximum flooding surfaces identified by regional marker shales, biofacies population and biodiversity charts and sequence stratigraphic methods like sequence thickness, bed stacking patterns and facies depositional patterns with regards sea level change. It was noticed that reservoir thickness reduces from the bottom to the top with the proximal channel sands in deep intervals gradually overlain by distal upper shoreface sands and lower shoreface sands at the shallower intervals. The gross depositional environment was a transgressive marine settings ranging from the lower shoreface and channelized upper shoreface deposits. The results from the integration of facies analysis, biofacies, seismic analysis and sequence stratigraphy results reduces uncertainty in depositional environment models.

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Karakteristik Perubahan Lingkungan Akhir Plistosen - Holosen di Dataran Rendah Aluvial dan Pantai Wilayah Demak, Kudus, Jepara, Pati dan Sekitaranya

Jurnal Lingkungan dan Bencana Geologi ◽

10.34126/jlbg.v12i1.262 ◽

2021 ◽

Vol 12 (1) ◽

pp. 17

Author(s):

Rio A.T. Moechtar ◽

Subiyanto Subiyanto ◽

R.I.H Sulistyawan

Keyword(s):

Climate Change ◽

Sea Level ◽

Depositional Environment ◽

Deposition Process ◽

Alluvial Plain ◽

Sea Level Fluctuations ◽

Stratigraphic Analysis ◽

External Process ◽

Holocene Sediments ◽

Sea Level Fluctuation

ABSTRAKWilayah dataran aluvial hingga pantai daerah Demak, Kudus, Jepara, Pati dan sekitarnya ditutupi endapan sedimen Holosen yang terdiri atas kerikil, pasir, lempung, lanau, dan bongkah batuan gunungapi. Penelitian dilakukan dengan analisis sedimentologi dan stratigrafi terhadap 37 pemboran berskala 1 : 100 dengan ketebalan sedimen antara 0,8 - 18 meter. Berdasarkan korelasi data hasil pemboran diketahui bahwa sedimen Holosen di wilayah ini dapat dibedakan dalam tiga interval proses pengendapan (IPP A- C). Perubahan sedimen secara vertikal dapat diwakili oleh setiap sub-IPP yang merupakan hasil dari proses eksternal sesuai perubahan iklim, fluktuasi muka laut, tektonik dan aktivitas gunungapi. Dari hasil analisis stratigrafi diketahui bahwa perubahan lingkungan pengendapan pada daerah penelitian berhubungan dengan aktivitas proses eksternal di cekungan ini. Peranan proses eksternal ini diharapkan menjadi variabel dalam perumusan kebijakan pengelolaan lingkungan di wilayah Demak, Kudus, Jepara, Pati, dan sekitarnya.Kata kunci: fluktuasi muka air laut, Holosen, lingkungan, tektonik, perubahan iklimABSTRACTThe alluvial plain to the coast of Demak, Kudus, Jepara, Pati, and its surroundings is covered with sedimentary Holocene deposits consisting of gravel, sand, clay, silt, and volcanic rock boulders. The study used sedimentology and stratigraphic analysis of 37 drilling points with sediment thicknesses between 0.8-18 meters. Based on the correlation of drilling results, the Holocene sediments in the area of research can be distinguished in three deposition process (IPP) intervals. Vertically, sediment changes can be represented by each sub-IPP which are the result of external processes according to climate change, sea-level fluctuations, tectonics, and volcanic activity. From the results of the stratigraphic analysis, the changes in the depositional environment in the study area are related to external process activities in the basin. The effects of this external process are expected to be a recommendation in the future environmental development in the Demak, Kudus, Jepara, Pati, and its surroundings.Keywords: sea-level fluctuation, Holocene, environment, tectonic, climate change

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