Geoscience Laboratory

Islamabad, Pakistan

Geoscience Laboratory

Islamabad, Pakistan
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Yamamoto H.,Kagoshima University | Rehman H.U.,Kagoshima University | Kaneko Y.,Yokohama National University | Kaneko Y.,Meisei University | Kausar A.B.,Geoscience Laboratory
Journal of Asian Earth Sciences | Year: 2011

Metamorphosed volcanic and sedimentary rocks of the Jaglot Group are exposed along the west bank of the Indus River near Thelichi. The structural bottom unit, the Thelichi Formation, is composed of metavolcaniclastic, metavolcanic, metapelitic, and metacalcareous rocks. Bedding planes of the Thelichi Formation trend E-W or NW-SE and dip steeply to the N. The middle unit, Gashu-Confluence Volcanics, is composed of metavolcaniclastic, metavolcanic, and metacalcareous rocks. Bedding planes trend NW-SE and dip moderately to the N. The top unit, the Gilgit Formation, is composed of interlayered metapsammitic and metapelitic rocks. Graded bedding, cross-bedding, and pillow structures are preserved in these metamorphic rocks of the Jaglot Group. Those indicate clastic sedimentary and volcanic origins. There is no major repetition of layers due to folding (so-called " the Jaglot syncline") as is evidenced by the consistent northward younging of the beds. The three lithological units constitute a north-dipping tectonic stack. The tectonic stack was provably caused by the northward subduction of the back-arc basin under the Asian margin and subsequent collision between the Asia and the Kohistan (the closure of back-arc basin). © 2010 Elsevier Ltd.

Nishimura T.,Tottori University | Fukuda T.,Geoscience Laboratory | Kiyama H.,Tottori University
Zairyo/Journal of the Society of Materials Science, Japan | Year: 2010

Rockfall hazard zoning is not simple to achieve in practice. It involves the different factors: rock block shape and size, characteristics of the topography, and the occurrence of rockfall which depends on some triggering events that cause a change in the forces acting a rock block. Rockfall hazard maps are often replaced with figures which show the frequency and the corresponding intensity of a predefined rock magnitude. Some attempts are introducing the results of the three-dimensional numerical modeling to get the objective zoning based on the mechanical parameters (e.g. kinetic energy). In such attempts, it is important to recognize that the mechanical parameters may be affected by modeling of the physical factors mentioned above. The most important role of the three-dimensional simulation is to display the lateral dispersion of trajectories. In this paper, the influence of controlling factors on the dispersion has been evaluated by conducting 3D simulation. Parametric simulations have been performed at different spatial resolutions using sets of synthetic biplanar slopes characterized by mean inclination and local asperities. The results of the lateral dispersion of trajectories are explained with the width of computed trajectories and the fixed distance along the slope surface from the block launch position. © 2010 The Society of Materials Science, Japan.

Masuda H.,Osaka City University | Mitamura M.,Osaka City University | Farooqi A.M.,Osaka City University | Farooqi A.M.,Fatima Jinnah Women University | And 5 more authors.
Geochemical Journal | Year: 2010

To constrain the origin of fluoride and arsenic contamination of groundwater in Kalalanwala, Punjab, Pakistan, the geochemical and mineralogical characteristics of the aquifer were studied. Subsurface geology of the area was studied using data from drilled cores. The residential and industrial areas including Kalalanwala are covered with Pleistocene aeolian deposits. These sediments cover two aquifers intercalated by a less permeable layer. Most polluted groundwater appears in the first aquifer at 15 to 25 m depth beneath the center of the village of Kalalanwala. A considerable amount of anthropogenic fluoride contaminates the aquifer along an ancient river channel. Arsenic might derive from anthropogenic sources such as industrial waste, or detrital chlorite. Copyright © 2010 by The Geochemical Society of Japan.

Qureshi A.A.,Institute of Information Technology | Ali M.,Institute of Information Technology | Waheed A.,Institute of Information Technology | Manzoor S.,Institute of Information Technology | And 2 more authors.
Radiation Protection Dosimetry | Year: 2013

The Lawrencepur sand had remained refrigerated during a long period of glaciations in the study area. Owing to its derivation from the granitic rocks of the Himalayas and its preservation under glacial environment, the sand grains are still fresh and may contain high level of primordial radioactivity. For that reason, radiological hazards of Lawrencepur sand were assessed using a high-purity germanium gamma spectrometry technique. The average activity concentrations of 226Ra, 232Th and 40K were found to be 15.97±3.05, 27.98±4.89 and 498.20±15.91 Bq kg-1, respectively. These values are higher than those of the sands of many countries of the world but lower than those of some of the Pakistani, Indian and Egyptian sands. The outdoor and indoor hazard indices and annual effective doses of the Lawrencepur sand are higher than those of some of the sand deposits of European, African and American countries but lower than those of nearby Pakistani and Indian sands. However, the hazard indices and annual effective doses of the Lawrencepur sand are within the safe limits. Overall, the Lawrencepur sand does not pose any radiological health hazard as a building material. © The Author 2013. Published by Oxford University Press.

Zaman H.,King Saud University | Otofuji Y.-I.,Kobe University | Khan S.R.,Geoscience Laboratory | Ahmad M.N.,Geoscience Laboratory
Arabian Journal of Geosciences | Year: 2013

Different phases of remanent magnetizations have been identified in the Cretaceous-Tertiary rocks collected from the northern margin of the Kohistan Island Arc, northern Pakistan. Among them, a magnetite-related component is recognized as the most useful one because of its relatively stable behaviour and widespread presence in the volcanics and red beds. Calculation of mean direction for this component reveal two visible groupings in terms of paleomagnetic directions (Yasin + Baris Group: D = 341. 6o, I = 10. 6o, α95 = 23. 3 o, k = 11. 7, N = 5; Sandhi Group: D = 28. 4o, I = -27. 4o, α95 = 32. 5 o, k = 8. 96, N = 4). The fold tests applied to both these groups are inconclusive, indicating a syn-folding to post-folding origin for this component. A set of inclinations from this study provide new insight into post-collision northward displacement of the Kohistan Arc with respect to its surrounding terranes. Reliability of the paleomagnetic declinations from this study is not fully guaranteed, but when compared with previously reported paleomagnetic directions, a systematic increase in counter-clockwise deflections towards west has been detected along this paleo-island arc. This trend of declinations is well matched with the extrusion model of Asia, where counter-clockwise rotation has been suggested for the tectonic terranes around Western Himalaya. Another important observation is a divergence in paleomagnetic declinations across the rivers, which may indicate the presence of faulted zones under the cover of flowing water. This aspect can be compared to recent geological interpretations that Kohistan may not have acted as a rigid block following its collision with India but may have been deformed through localized shears and faults. © 2011 Saudi Society for Geosciences.

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