Coesite relics were discovered as inclusions in clinopyroxene in eclogite and as inclusions in zircon in felsic and pelitic gneisses from Higher Himalayan Crystalline rocks in the upper Kaghan Valley, northwest Himalaya. The metamorphic peak conditions of the coesite-bearing eclogites are estimated to be 27-32 kbar and 700-770°C, using garnet-pyroxene-phengite geobarometry and garnet-pyroxene geothermometry, respectively. Cathodoluminescence (CL) and backscattered electron (BSE) imaging distinguished three different domains in zircon: inner detrital core, widely spaced euhedral oscillatory zones, and thin, broadly zoned outermost rims. Each zircon domain contains a characteristic suite of micrometre-sized mineral inclusions which were identified by in situ laser Raman microspectroscopy. Core and mantle domains contain quartz, apatite, plagioclase, muscovite and rutile. In contrast, the rim domains contain coesite and minor muscovite. Quartz inclusions were identified in all coesite-bearing zircon grains, but not coexisting with coesite in the same growth domain (rim domain). 206 Pb ⁄ 238 U zircon ages reveal that the quartz-bearing mantle domains and the coesite-bearing rim were formed at c. 50 Ma and 46.2 ± 0.7 Ma, respectively. These facts demonstrate that the continental materials were buried to 100 km within 7-9 Myr after initiation of the India-Asia collision (palaeomagnetic data from the Indian oceanic floor supports an initial India-Asia contact at 55-53 Ma). Combination of the sinking rate of 1.1-1.4 cm year )1 with Indian plate velocity of 4.5 cm year )1 suggests that the Indian continent subducted to about 100 km depth at an average subduction angle of 14-19°.
In the global economy, tourism is one of the most noticeable and growing sectors. This sector plays an important role in boosting a nation’s economy. An increase in tourism flow can bring positive economic outcomes to the nations, especially in gross domestic product (GDP) and employment opportunities. In South Asian countries, the tourism industry is an engine of economic development and GDP growth. This study investigates the impact of tourism on Pakistan’s economic growth and employment. The period under study was from 1990 to 2015. To check whether the variables under study were stationary, augmented Dickey–Fuller and Phillips–Perron unit root tests were applied. A regression technique and Johansen cointegration approach were employed for the analysis of data. The key finding of this study shows that there is a positive and significant impact of tourism on Pakistan’s economic growth as well as employment sector and there is also a long-run relationship among the variables under study. This study suggests that legislators should focus on the policies with special emphasis on the promotion of tourism due to its great potential throughout the country. Policy implications of this recent study and future research suggestions are also mentioned.
The Kohistan-Ladakh Arc in the Himalaya-Karakoram region represents a complete section of an oceanic arc where the rocks from mantle to upper crustal levels are exposed. Generally this arc was regarded as of Jurassic-Cretaceous age and was welded to Asia and India by Northern and Southern Sutures respectively. Formation of this arc, timings of its collisions with Asia and India, and position of collision boundaries have always been controversial. Most authors consider that the arc collided with Asia first during 102-75 Ma and then with India during 55-50 Ma, whereas others suggest that the arc collided with India first at or before 61 Ma, and then the India-arc block collided with Asia ca 50 Ma. Recently published models of the later group leave several geological difficulties such as an extremely rapid drifting rate of the Indian Plate (30 Ϯ 5 cm/year) northwards between 61-50 Ma, absence of a large ophiolite sequence and accretionary wedge along the Northern Suture, obduction of ophiolites and blueschists along the Southern Suture, and the occurrence of a marine depositional environment older than 52 Ma in the Indian Plate rocks south of the Southern Suture. We present a review based on geochemical, stratigraphic, structural, and paleomagnetic data to show that collision of the arc with Asia happened first and with India later.
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