فهرس المقالات paleoenvironment

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  1 - Paleoenvironmental Reconstruction of Miocene Surma Succession in the Well Rashidpur # 04 of Bengal Basin Using Log Facies Interpretation
  Md. Ahosan Habib Abu Reza Md. Towfiqul Islam
  Detailed log facies studies of Miocene succession in the well Rashidpur-04, Rashidpur structure, Surma Basin were carried out by integrating wireline log and limited core sample data in order to reconstruct the paleoenvironments of deposition. Based on the analysis of t أکثر

  Detailed log facies studies of Miocene succession in the well Rashidpur-04, Rashidpur structure, Surma Basin were carried out by integrating wireline log and limited core sample data in order to reconstruct the paleoenvironments of deposition. Based on the analysis of the log motifs, grain size, sand/shale ratio and major change in gamma ray log motifs, two major depositional sequences were identified in the well Rashidpur-04 which consists of 17 para-sequences sets and 22 para-sequences. Serrated bell, funnel, cylindrical, egg/bow and linear log facies were recognized in the study well. Lithology indicates that the whole well interval consist of alteration of sandstone, siltstone, shale and prodelta facies. The Rashidpur sequence-2 inferred to be deposited in tidal flat to shallow marine conditions in prograding and retrograding delta front condition whereas the Rashidpur sequence-1 assumed to be deposited under tidal channel, distributary channel, tidal flat, mudflat, marine inter-distributary bay to shallow and deep marine conditions. The Rashidpur sequence-2 was deposited in comparatively deep water condition while the Rashidpur sequence-1 was deposited in relatively shallow water condition. The present study can be concluded that Miocene succession was coarsening upward in nature and might have deposited under prograding deltaic system. تفاصيل المقالة
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  2 - Paleoecology of Early to Middle Miocene Deposits (Guri Member) and Sedimentary Environment, SE Zagros Zone, Roydar, Iran
  Roya Fanati Rashidi Seyed Hamid Vaziri Keyvan Khaksar Hossein Gholamalian
  This research focusses on the facies distribution, paleoenvironment and paleoecology of the foraminifera of the Guri Member in the northern Bandar Abbas Hinterland located in the Roydar area of southern Iran. The Guri Member is 570 meters thick and composed of limestone أکثر

  This research focusses on the facies distribution, paleoenvironment and paleoecology of the foraminifera of the Guri Member in the northern Bandar Abbas Hinterland located in the Roydar area of southern Iran. The Guri Member is 570 meters thick and composed of limestone, argillaceous limestone and marl. The distribution of the foraminifera in the study area indicates the existence of three biozones ranging from early to middle Miocene in age. Based on petrographical studies, depositional textures and fauna, eight microfacies were identified. The paleoecology, lithology and environmental interpretations were characterized by an open marine environment with an upward, gradually shallowing trend. Additionally, three distinct depositional settings were identified: tidal flat, inner ramp and middle ramp. Microfacies (MF) 1, representing a distal middle ramp setting, was characterized by the occurrence of hyaline, benthic and planktonic foraminifera. MF2 and MF3 were characterized by the occurrence of Miogypsina, Elphidium and red algae. They represent a deeper low energy in the wave base of a middle ramp setting. MF4 was characterized by an abundance of rotaliids and red algae representing a proximal middle ramp environment. MF5 and MF6 were identified by the occurrence of large and small porcelaneous benthic foraminifera representing a shallow-water inner ramp setting. MF7 and MF8 were characterized by the occurrence of gastropods and bivalves in a shallow-water setting of tidal flats influenced by both wave and tidal processes. Palaeolatitudinal reconstructions based on skeletal grains suggest that the Guri Member existed in tropical waters within a carbonate ramp. تفاصيل المقالة
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  3 - Palynology and paleoenvironmental study of the Kalat Formation in the east of the Kopet – Dagh sedimentary basin
  Mohsen Allameh Ebrahim Ghasemi-Nejad Abdollah Saeidi
  The Kopet–Dagh sedimentary basin stretches in northeastern Iran as narrow and long ranges and contains sediments of the Jurassic to recent ages. One of the lithostratigraphic units in this basin is the Kalat Formation with an age of the latest Cretaceous. The Form أکثر

  The Kopet–Dagh sedimentary basin stretches in northeastern Iran as narrow and long ranges and contains sediments of the Jurassic to recent ages. One of the lithostratigraphic units in this basin is the Kalat Formation with an age of the latest Cretaceous. The Formation is made up of sandy limestones and shales. In order to study the palynology, palynofacies and paleoenvironment of these Formations three sections, Chahchahe, Tange–Neyzar and Padly, were sampled palynologically and the samples were prepared and studied. Some of the samples proved to be rich in dinoflagellates and some 40 species belonging to 29 genera were recorded. Palynofacies studies show that the Formation was deposited in a shallow- open marine environment with moderate to high energy conditions. تفاصيل المقالة