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Late Maastrichtian through middle Eocene planktic foraminiferal biostratigraphy and erosion patterns from three Cauvery basin wells are compared with the Krishna-Godavari basin, Madagascar and South Atlantic Site 525A. Maastrichtian sedimentation appears continuous at DSDP site 525A and substantially complete in the Cauvery basin and Madagascar for the interval from ~70.3 to 66.8 Ma (zones CF6-CF3). But the latest Maastrichtian through early Paleocene record is fragmented, except for some Krishna-Godavari and Cauvery basin wells protected from erosion by Deccan traps or graben deposition, respectively. Hiatuses are observed correlative with sea level falls at 66.8, 66.25, 66.10, 65.7, 63.8 and 61.2 Ma with erosion amplified by local tectonic activity including doming and uplift due to Deccan volcanism.  相似文献   
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Daily rain series from southern Sweden with records dating back to the 1870s have been analysed to investigate the trends of daily and multi‐day precipitation of different return periods with emphasis on the extremes. Probabilities of extreme storms were determined as continuously changing values based on 25 years of data. An extra set of data was used to investigate changes in Skåne, the southernmost peninsula of Sweden. Another 30‐year data set of more than 200 stations of a dense gauge network in Skåne was used to investigate the relation between very large daily rainfall and annual precipitation. The annual precipitation has increased significantly all over southern Sweden due to increased winter precipitation. There is a trend of increasing maximum annual daily precipitation at only one station, where the annual maximum often occurs in winter. The number of events with a short return period is increasing, but the number of more extreme events has not increased. Daily and multi‐daily design storms of long return periods determined from extreme value analysis with updating year by year are not higher today than during the last 100 years. The largest daily storms are not related to stations with annual rainfall but seem to occur randomly. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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Climate variability has been evident on the Mongolian plateau in recent decades. Livelihood adaptation to climate variability is important for local sustainable development. This paper applies an analytical framework focused on adaptation, institutions, and livelihoods to study climate adaptation in the Mongolian grasslands. A household survey was designed and implemented in each of three broad vegetation types in Mongolia and Inner Mongolia. The analytical results show that livelihood adaptation strategies of herders vary greatly across the border between Mongolia and Inner Mongolia, China. Local institutions played important roles in shaping and facilitating livelihood adaptation strategies of herders. Mobility and communal pooling were the two key categories of adaptation strategies in Mongolia, and they were shaped and facilitated by local communal institutions. Storage, livelihood diversification, and market exchange were the three key categories of adaptation strategies in Inner Mongolia, and they were mainly shaped and facilitated by local government and market institutions. Local institutions enhanced but also at times undermined adaptive capacity of herder communities in the two countries, but in different ways. Sedentary grazing has increased livelihood vulnerability of herders to climate variability and change. With grazing sedentarization, the purchase and storage of forage has become an important strategy of herders to adapt to the highly variable climate. The multilevel statistical models of forage purchasing behaviors show that the strategies of livestock management, household financial capital, environmental (i.e., precipitation and vegetation growth) variability, and the status of pasture degradation were the major determinants of this adaptation strategy.  相似文献   
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The Dupi Tila Formation is composed of yellow to light brown medium to very fine moderately hard to loose sandstone, siltstone, silty clay, mudstone and shale with some conglomerates with clasts of petrified wood. The lithofacies of matrix supported conglomerate, trough cross bedded conglomerate, massive sandstone, trough cross bedded sandstone, planar cross bedded sandstone, ripple cross laminated sandstone-siltstone, flaser laminated sandstone-shale, lenticular laminated sandstone-siltstone-shale, parallel laminated sandstone-siltstone, wavy laminated shale, parallel laminated blue shale, and mudstone are delineated within this formation. Based on the grain size, sedimentary structures, water depth and genesis of individual facies, facies are grouped into three types of facies associations like (i) coarse-grained conglomerate facies association in relation to tractive current deposits of alluvial fan set up at the base of litho-succession (FAC), (ii) medium to fine-grained sandstone-siltstone-mudstone facies association or facies association in relation to strong tide (FAT) characterizing the middle part of litho-succession, (iii) very fine-grained sandstone-siltstone-mudstone facies association in relation to less frequent weak tide or heterolithic facies association (FAHL) characterizing upper part of litho-succession and shallow marine facies association (FASM) composing the uppermost litho-succession. Presence of gluconite indicates that the depositional environment was shallow to deep marine. The dominant paleoflow direction during the deposition of Dupi Tila Formation was toward southeast to southwestern direction. The rivers were of braided type at the piedmont alluvial depositional set up at the lower part, which later changed to estuarine-tidal flat type environmental set up in the middle part to upper part and paleo-environment was shallow marine in the uppermost part.  相似文献   
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Saraf  Arun K.  Rawat  Vineeta  Das  Josodhir  Zia  Mohammed  Sharma  Kanika 《Natural Hazards》2012,61(2):861-872
Prior to the occurrence of an earthquake, the region undergoes intensive physiochemical changes. Such changes trigger degassing charge generation leading to positive change in the thermal regime and consequently creation of an earthquake preparation zone. These changes in thermal regime can be detected by the thermal sensors onboard various polar orbiting satellites. Recent researches have demonstrated that thermal infrared sensors onboard satellites (e.g., NOAA-AVHRR and Terra/Aqua-MODIS) can detect temporal transient thermal infrared anomalies prior to an earthquake. The paper presents satellite-based thermal observations associated with Yamnotri (July 22, 2007, India), Ravar (October 14, 2004, Iran) and Dalbandin (January 19, 2011, Pakistan) earthquakes. In the case of Yamnotri earthquake, the region attained around 5–8°C higher than the normal temperature on July 21, 2007 in the area, just 1 day before the earthquake. Whereas, in the case of Ravar earthquake, the region has shown 5–7°C higher temperature on October 06, 2004 about 6 days before the occurrence of the main earthquake event. Dalbandin earthquake showed a maxima on January 17, 2011, just 2 days before the main shock with the raised temperature of around 8–10°C. Another common observation in all these earthquakes is the disappearance of short-term transient thermal anomaly just before the main shock.  相似文献   
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