Anabar-Lena Composite Tectono-Sedimentary Element, Northern East Siberia

Anabar-Lena Composite Tectono-Sedimentary Element (AL CTSE) is located in the northern East Siberia extending for c. 700 km along the Laptev Sea coast between the Khatanga Bay and Lena River delta. AL CTSE consists of rocks from Mesoproterozoic to Late Cretaceous in age with total thickness reaching 14 km. It evolved through the following tectonic settings: (1) Meso-Early Neoproterozoic intracratonic basin, (2) Ediacaran - Early Devonian passive margin, (3) Middle Devonian - Early Carboniferous rift, (4) late Early Carboniferous - latest Jurassic passive margin, (5) Permian foreland basin, (6) Triassic to Jurassic continental platform basin and (7) latest Jurassic - earliest Late Cretaceous foreland basin. Proterozoic and lower-middle Paleozoic successions are composed mainly by carbonate rocks while siliciclastic rocks dominate upper Paleozoic and Mesozoic sections. Several petroleum systems are assumed in the AL CTSE. Permian source rocks and Triassic sandstone reservoirs are the most important play elements. Presence of several mature source rock units and abundant oil- and gas-shows (both in wells and in outcrops), including a giant Olenek Bitumen Field, suggest that further exploration in this area may result in economic discoveries.

Seismic Geomorphology Of Channels In X-Block, Penyu Basin

Penyu Basin is a complex, intracratonic basin, situated on the northern Sunda Shelf. This basin formed during Oligocene, and geological setting of this area is a typical Southeast Asian Tertiary rift system. An oil discovery has been made in X-Block of Penyu Basin. However, it was relinquished in 2006 due to the non-commercial oil discovery. X-Block consists of mostly monoclinal structures that do not seem to provide an efficient trapping mechanism because of the very low reliefs. Three wells have been drilled in X-Block and tested primarily on the structural traps, mainly the basement drape structures. This research aims to analyze the stratigraphic traps, focusing on channel features. This is done with the aid from seismic geomorphology. This method helps examine buried landforms by using seismic data as a tool. By seismic geomorphology study, several channel features can be recognized. Most of the channels can be found in upper and middle part of the seismic section. As going deeper to the bottom section, only lineaments of faults are visible. In the upper part of the seismic section, straight and long channel features can be observed and as moving downwards, the channel sinuosity increases resulting in meandering channel. From this seismic geomorphology study, it confirms that there are channel systems in X-Block of Penyu Basin.

Structural Diagenesis in Carbonate Rocks as Identified in Fault Damage Zones in the Northern Tarim Basin, NW China

The identification of structural diagenesis and the reconstruction of diagenetic paragenesis in fault damage zones is important for understanding fault mechanisms and fluid flow in the subsurface. Based on the examination of core and sample thin section data, we deciphered the diagenetic parasequence and their fault controls for Ordovician carbonates in the northern Tarim intracratonic basin in NW China (Halahatang area). In contrast to the uniform nature of diagenesis observed in country rocks, there is a relatively complicated style of compaction and pressure solution, multiple fracturing, and cementation and dissolution history along the carbonate fault damage zones. The relative paragenetic sequence of the structure related diagenesis suggests three cycles of fracture activities, following varied fracture enlargement and dissolution, and progressively weaker calcite cementation. These processes of structure related diagenesis are constrained to the fault damage zones, and their variation is affected by the fault activities. The results of this study suggest that the carbonate reservoir and productivity could be impacted by the structure related diagenesis locally along the fault damage zones.

Facies analysis and paleosol characterization of Urucuia group in the Sao Domingos - GO region

The Sanfranciscana basin is a wide intracratonic basin sub-divided in Abaeté sub-basin and Urucuia sub-basin which includes four Groups of Neo Paleozoic to Neo Cretaceous ages, among them there is the target of this study, the Urucuia Group (Upper Cretaceous). The Urucuia Group has the largest rock volume and areal distribution of the basin. Its rocks constitute two Formations, the basal named Posse overlaid by Serra das Araras Formation. In a continental environment where there is a few fossil contents, the paleosol study can bring important information about climatic and geomorphologic conditions, and biological activity being possible to do an environmental reconstruction. Therefore, this project aims to elaborate a paleoenvironmental model to the Upper Cretaceous of the Sanfraciscana basin through facies analysis and paleosol characterization. The fieldwork was accomplished in the outcrops of the Urucuia Group situated near to São Domingo (GO) town. Outcrop descriptions, photographic registration, and sample collection to laboratory analysis were the methodology applied. The outcrop description was made by the identification of lithologies, textures, sedimentary structures, paleocurrents, fossil content, bed geometry, as well as paleosol macromorphologic description.