scholarly journals Stratigraphy and structure of the Peshawar basin, Pakistan

1998 ◽  
Vol 18 ◽  
Author(s):  
Ahmad Hussain ◽  
Joseph A. Dipietro ◽  
Kevin R. Pogue

The Peshawar intermontane basin is a broad, oval shaped and low-lying depression at the southern margin of the Himalaya. It lies to the north of the Attock-Cherat Range and contains rocks transitional between the sedimentary fold-thrust belt to the south and a metamorphic terranc to the north. The basin came into existence as the Kalachitta Range was faulted south on the Main Boundary Thrust (MBT pushing the Siwalik foreland basin still farther south. The basin sediments predominantly comprise of the lacustrine, deltaic and fluvial deposits, which arc overlain by loess, flood plain and alluvial fans of younger age. As a result of the present study, especially the findings of conodonts, the bedrock sequence of the Peshawar basin established previously, has been modified and revised. An almost complete sequence of rocks ranging from the Precambrian to Triassic age has been established for the first time in the Peshawar basin. The study of the Landsat data, aerial photographs and subsequent field studies indicate presence of zone of late Quaternary deformation that extends across the southern margin of the Peshawar basin. Lacustrine, fluvial and alluvial fan deposits, which are dated at 2.8 to 0.6 Ma are tilted, folded and faulted along the four left-stepping pressure ridges that extend for nearly 60 km. Alluvial-fan and fluvial sediments are also folded and faulted in the Ghazi area where the base of the Indus River appears to be displaced by a reverse fault with its northwest side up. Additional minor lineaments and faults occur parallel and oblique to the major fault structures.

Geosciences ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 363 ◽  
Author(s):  
Hideaki Goto ◽  
Kohsaku Arai ◽  
Taichi Sato

Anaglyphs produced using a digital elevation model (DEM) are effective to identify the characteristic tectono–geomorphic features. The objective of this study is to reinvestigate the tectonic geomorphology and to present novel tectonic maps of the late Quaternary in and around the Yoron island based on the interpretation of extensive topographical anaglyphs along the map areas that cover the inland and seafloor. Vintage aerial photographs are used to produce the 3-m mesh inland digital surface model (DSM); further, the 0.6-s to 2-s-mesh seafloor DEM is processed using the cloud point data generated through previous surveys. Thus, we identify anticlinal deformation on both the Pleistocene marine terrace and the seafloor to the north of the island. The deformation axis extends in a line and is parallel to the general trend of the island shelf. The Tsujimiya fault cuts the marine terraces, which extend to the Yoron basin’s seafloor. If we assume that the horizontal compressive stress axis is perpendicular to the island shelf, these properties can easily explain the distribution and style of the active faults and deformation. This study presents an effective methodology to understand the island arc tectonics, especially in case of small isolated islands.


1970 ◽  
Vol 11 ◽  
pp. 61-70
Author(s):  
Mukunda Raj Paudel ◽  
Harutaka Sakai

Quatenary fluvio-lacustrine basin-fill sediments in the southern part of the Kathmandu Basin was studied in order to clearify the stratigraphy and reconstruct the sedimentary environment during the initial stage of the Paleo-Kathmandu Lake. Six stratigraphic units; Tarebhir, Lukundol, Itaiti, Kalimati, Sunakothi Formations and Terrace gravel deposits, have been described based on field observation of lithology and sediment distribution. The Tarebhir Formation is the basal unit which is overlained by alluvial fan of the Itaiti Formation in the southern part and by the marginal lacustrine deposit of the Lukundol Formation towards the northern part. Further 3 km toward the north from the basin margin at Jorkhu the the Lukundol Formation is overlain by the open lacustrine facies of the Kalimati Formation. At the same locality the latter is overlain by fluvio-lacustrine facies of the Sunakothi Formation. Moreover, the Terrace gravel deposits erosionally cover the Sunakothi Formation. The Kalimati Formation thickens northward, while the Sunakothi Formation thickens between the central and southern part of the basin. The study shows that the Sunakothi Formation is of fluvio-lacustrine (fluvial, deltaic and shallow lacustrine) origin and extends continuously from the southern margin (~1400m amsl) to the central part (~1300m amsl) of the basin. It also indicates that sediments of this formation were deposited at the time of lake level rise and fall. Thick gravel sequence in the southern margin represents the alluvial fan before the origin (before 1 Ma) of the Paleo-Kathmandu Lake, while thick gravel sequence situated above the Sunakothi Formation is the Terrace gravel deposits of the late Pleistocene age (14C method), deposited during and after the shrinkage of the Paleo-Kathmandu Lake from south to north.   doi: 10.3126/bdg.v11i0.1544 Bulletin of the Department of Geology, Tribhuvan University, Kathmandu, Nepal, Vol. 11, 2008, pp. 61-70


2021 ◽  
pp. 228775
Author(s):  
Qingri Liu ◽  
Youli Li ◽  
Jianguo Xiong ◽  
Huiping Zhang ◽  
Weipeng Ge ◽  
...  

The Holocene ◽  
2020 ◽  
pp. 095968362098168
Author(s):  
Christian Stolz ◽  
Magdalena Suchora ◽  
Irena A Pidek ◽  
Alexander Fülling

The specific aim of the study was to investigate how four adjacent geomorphological systems – a lake, a dune field, a small alluvial fan and a slope system – responded to the same impacts. Lake Tresssee is a shallow lake in the North of Germany (Schleswig-Holstein). During the Holocene, the lake’s water surface declined drastically, predominately as a consequence of human impact. The adjacent inland dune field shows several traces of former sand drift events. Using 30 new radiocarbon ages and the results of 16 OSL samples, this study aims to create a new timeline tracing the interaction between lake and dunes, as well, as how both the lake and the dunes reacted to environmental changes. The water level of the lake is presumed to have peaked during the period before the Younger Dryas (YD; start at 10.73 ka BC). After the Boreal period (OSL age 8050 ± 690 BC) the level must have undergone fluctuations triggered by climatic events and the first human influences. The last demonstrable high water level was during the Late Bronze Age (1003–844 cal. BC). The first to the 9th century AD saw slightly shrinking water levels, and more significant ones thereafter. In the 19th century, the lake area was artificially reduced to a minimum by the human population. In the dunes, a total of seven different phases of sand drift were demonstrated for the last 13,000 years. It is one of the most precisely dated inland-dune chronologies of Central Europe. The small alluvial fan took shape mainly between the 13th and 17th centuries AD. After 1700 cal. BC (Middle Bronze Age), and again during the sixth and seventh centuries AD, we find enhanced slope activity with the formation of Holocene colluvia.


2020 ◽  
pp. 1-21
Author(s):  
Zili Zhang ◽  
Xiaomin Zhu ◽  
Ruifeng Zhang ◽  
Sheng Fu ◽  
Jing Zhang

In addition to core, logging, and other previous research results, this paper determines the fault development and tectonic evolution process of the Baxian sag with the Paleogene rift stage based on 3D seismic data. The Paleogene tectonic evolution of the sag can be divided into three episodes and six evolution stages, and three types of faults are identified: intensely active normal, active normal, and weakly active normal. One first-order sequence, three second-order sequences, and fourteen third-order sequences of the Paleogene Baxian sag were created, and fifteen sequence boundaries were recognised. According to the rifting background and sedimentary facies development characteristics of each episode, five combination types of the depositional system associations were identified, including alluvial fan-fluvial and braided-delta-lacustrine in an early rifting episode, delta-lacustrine and nearshore subaqueous fan-lacustrine in the middle rifting episode, and fluvial-flood plain in the late rifting episode. Six response models of filling and the evolution process in Paleogene Baxian sag were concluded. The multi-episodes tectonic cycles of faulted lake basins resulted in complex paleogeomorphology and variable provenance supply, forming abundant sequence structure patterns and different filling and evolution processes of faulted lake basins. The stable rifting stage is favourable to form and preserve high-quality source rock, and develop various sedimentary facies and sandbody types, which is a potential area for exploration of a lithologic stratigraphic oil and gas reservoir.


2010 ◽  
Vol 222 (1-2) ◽  
pp. 209-220 ◽  
Author(s):  
Edit Thamó-Bozsó ◽  
Árpád Magyari ◽  
Balázs Musitz ◽  
Attila Nagy

Antiquity ◽  
1995 ◽  
Vol 69 (265) ◽  
pp. 818-830 ◽  
Author(s):  
Geoff Hope ◽  
Jack Golson

At the south and north limits of our region are mountainous areas very different from the open arid spaces of the Australian continent between. In the north, the high country of New Guinea offers a complex and well-studied environmental sequence as the arena for early and puzzling human adaptations, precursor of the extraordinary societies of the island today.


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