焰山、高山--内蒙古阿尔山火山群中的两座活火山

阿尔山火山群位于内蒙古自治区东部 ,地处大兴安岭中段西缘 ,地理坐标为 1 2 0°1 4′0 0″～ 1 2 1°1 0′0 0″E ,4 7°1 5′0 0″～ 4 7°4 5′0 0″N。火山构造单元上属大同 -大兴安岭新生代火山活动带 (黄镇国等 ,1 993)。火山活动具多期性 ,可分为上新世、更新世和全新世。火山产物覆盖在侏罗纪火山 -侵入岩之上 ,总体呈北东向展布 ,出露面积约 1 30 0 (km) 2 ,上新世为拉斑玄武岩 ,第四纪主要为碱性橄榄玄武岩。火山作用方式既有岩浆爆破式和溢流式 ,也有射气岩浆喷发。以往区域地质调查 ① ,② 和本次初步考察确定阿尔山火山群由 4…     

腾冲火山地质研究述评

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云南省2001年上半年地震活动综述

据云南数字地震台网测定 ,2 0 0 1年上半年云南省共记录到 3级以上地震 5 5次 (不含余震 ) :其中 3～ 3 9级地震 44次、 4～ 4 9级 5次、 5～ 5 9级 5次。 2 0 0 1年上半年云南地区地震活动最显著的特点是历史上少见的中强震连发 (表 1 )。表 1　云南地区 2 0 0 1年上半年 5级地震目录编号发震时间震中位置年月日农历时分秒北纬东经地名 震源深度震级ＭＬ ＭＳ精度12 0 0 1 2 19廿七 2 3-5 1-362 1°2 6′ 10 2°5 0′老挝 10ｋｍ 5 2 42 2 0 0 1 2 2 0廿八 0 3-0 2 -5 12 1°2 2′ 10 2°5 4′老挝 8ｋｍ 5 432 0 0 1 3 12十八 16-5 7…     

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东北地区2003年第三季度ML≥3.0地震目录

序号发震时间地　震　位　置月日时　分　秒北纬东经地　点震级(ML)深度(km) 精度1 71 42 0 1 5 2 4 940°31′ 1 2 3°0 3′辽宁省海城 3 1 1 2Ⅰ2 72 4 0 2 0 2 4 2 845°5 6′ 1 30°5 0′黑龙江省勃利 3 8Ⅰ3 81 2 0 5 5 1 7 0 5 2°2 8′ 1 2 3°42′黑龙江省塔河 3 7Ⅰ4 81 80 0 331 7 437°5 7′ 1 2 0°43′渤海 3 8Ⅱ5 91 91 9482 7 5 37°48′ 1 2 4°37′黄海 3 4Ⅱ6 92 0 0 82 5 30 0 4 5°1 6′ 1 2 5°1 3′吉林省松原 3 3Ⅰ792 2 0 0 2 95 7 95 3°1 7′ 1 2 4°0 2′黑龙江省漠河 3 2Ⅰ892 2 2 0 5 90 5 0 39°42′ 1 …     

长江中下游-南黄海地震带4次中强震前的地震活动特征

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2022年第6期封面

岱海（40°32′～40°37′N,112°37′～112°46′E）位于内蒙古自治区,属半干旱地区内陆湖泊. 面积约53 km²(2018年),受气候变化和人类活动影响,湖面萎缩,蓄水量减少,矿化度增加明显.     

东北地区2004年第三季度ML≥3．0地震目录

Theearthquakes (ML≥ 3 0 )catalgueofThirdquarterinNortheasternarea ,2 0 0 4序号 发震时间地震位置月日时分秒 　 北纬东经地点震级(ML)深度(km) 精度1 72 70 61 5 1 8 2 4 3° 32′ 1 2 5 1 4′伊通 3 5 2 0 12 82 1 2 1 1 41 7 0 4 1° 48′ 1 2 75 6′长白山 3 0 13 82 5 2 1 2 90 9 5 39° 2 8′ 1 2 2 1 0′普兰店 3 3 1 1 14982 2 2 4 34 1 42° 0 1′ 1 2 80 1′长白山 3 7 15 92 70 30 61 0 5 4 0° 31′ 1 2 30 1′岫岩与海城交界 3 5 1 3 1东北地区2004年第三季度M_L≥3.0地震目录$辽宁省地震监测中心@梁灿…     

东北地区2002年第四季度M_L≥3.0地震目录

Theearthquakes (ML≥ 3 0 )catalogueofFouthquarterinnortheasternarea ,2 0 0 2序号发　震　时　间地　　震　　位　　置月日时　分　秒北　纬东　经地　　点震级(ML)深度(km)精度110 90 9-3 8-3 4 0 48°48′ 13 0°2 9′黑龙江嘉荫 3 9822 10 12 13 -5 1-4 7 7 3 9°2 3′ 12 2°13′辽宁省普兰店 3 0 1113 10 2 5 0 5 -12 -0 5 5 40°3 6′ 12 2°5 2′辽宁省海城 3 6814 10 2 5 18-3 4-2 5 83 8°3 3′ 12 0°15′渤海 3 7 25 112 19-2 2 -3 2 5 3 8°2 2′ 12 0°2 6′黄海 3 5 26112 5 12 -2 0 -5 0 93 8°5 6′ 12 1…     

东北地区2003年第二季度M_L≥3.0级地震目录

序号 发　震　时　间地　震　位　置月日时　分　秒北　纬东　经地　　点震级(ML)深度(km) 精度1 42 0 2 0 70 0 0 45°1 9′ 1 2 4°5 5′吉林省松原 3 0Ⅰ2 441 85 0 2 9 63 9°43′ 1 2 1°46′辽宁省瓦房店 3 0 1 1Ⅱ3 491 0 2 40 6 7 3 8°3 8′ 1 2 0°3 6′渤海 3 2Ⅱ45 71 93 41 1 1 3 7°43′ 1 2 1°5 3′渤海 3 3Ⅱ5 5 82 2 0 40 0 0 45°1 8′ 1 2 4°3 5′吉林省松原 3 0Ⅰ65 90 0 460 0 0 45°1 4′ 1 2 4°41′吉林省松原 3 5Ⅰ75 3 0 0 60 42 6 1 40°3 1′ 1 2 3°0 4′辽宁省岫岩 3 0 1 0Ⅰ861 41 83 3 43 6…     

SCIENCE CHINA Earth Sciences SUBJECT INDEX TO VOLUME 57(2014)

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A Monte Carlo study of rainfall forecasting with a stochastic model

A procedure for short-term rainfall forecasting in real-time is developed and a study of the role of sampling on forecast ability is conducted. Ground level rainfall fields are forecasted using a stochastic space-time rainfall model in state-space form. Updating of the rainfall field in real-time is accomplished using a distributed parameter Kalman filter to optimally combine measurement information and forecast model estimates. The influence of sampling density on forecast accuracy is evaluated using a series of a simulated rainfall events generated with the same stochastic rainfall model. Sampling was conducted at five different network spatial densities. The results quantify the influence of sampling network density on real-time rainfall field forecasting. Statistical analyses of the rainfall field residuals illustrate improvement in one hour lead time forecasts at higher measurement densities.     

Distribution of throughfall and stemflow in multi‐strata agroforestry,perennial monoculture,fallow and primary forest in central Amazonia,Brazil

The partitioning of rain water into throughfall, stemflow and interception loss when passing through plant canopies depends on properties of the respective plant species, such as leaf area and branch angles. In heterogeneous vegetation, such as tropical forest or polycultural systems, the presence of different plant species may consequently result in a mosaic of situations with respect to quantity and quality of water inputs into the soil. As these processes influence not only the water availability for the plants, but also water infiltration and nutrient leaching, the understanding of plant effects on the repartitioning of rain water may help in the optimization of land use systems and management practices. We measured throughfall and stemflow in a perennial polyculture (multi‐strata agroforestry), monocultures of peach palm (Bactris gasipaes) for fruit and for palmito, a monoculture of cupuaçu (Theobroma grandiflorum), spontaneous fallow and primary forest during one year in central Amazonia, Brazil. The effect on rain water partitioning was measured separately for four useful tree species in the polyculture and for two tree species in the primary forest. Throughfall at two stem distances, and stemflow, differed significantly between tree species, resulting in pronounced spatial patterns of water input into the soil in the polyculture system. For two tree species, peach palm for fruit (Bactris gasipaes) and Brazil nut trees (Bertholletia excelsa), the water input into the soil near the stem was significantly higher than the open‐area rainfall. This could lead to increased nutrient leaching when fertilizer is applied close to the stem of these trees. In the primary forest, such spatial patterns could also be detected, with significantly higher water input near a palm (Oenocarpus bacaba) than near a dicotyledonous tree species (Eschweilera sp.). Interception losses were 6·4% in the polyculture, 13·9 and 12·3% in the peach palm monocultures for fruit and for palmito, respectively, 0·5% in the cupuaçu monoculture and 3·1% in the fallow. With more than 20% of the open‐area rainfall, the highest stemflow contributions to the water input into the soil were measured in the palm monocultures and in the fallow. Copyright © 1999 John Wiley & Sons, Ltd.     

Anthropogenic Eutrophication and Red Tide Outbreak in Lacustrine Systems of the Kashmir Himalaya

Red tide, a recurrent phenomenon has become conspicuous in several Kashmir lake ecosystems since 1991. The responsible organism (Euglena pedunculata), a rare flagellate rediscovered in the Kashmir Himalaya (Khan 1993) caused first and unprecedented red tide outbreak, constituting a maximum of 96% of resident numerical phytoplankton density in Dal Lake. At present, conflicting hypotheses exist on the generation of causal assemblage(s) imparting redness to waters: Jeeji Bai (1991) linked its origin to acid precipitation – a fallout of burning oil‐fields during the Gulf War – whilst Khan (1993) holds local factor(s) responsible. Field/experimental studies support the latter contention that the influx of untreated sewage, in unison with warm temperatures, high levels of PhAR, iron and interruption to hydrological flow‐pattern together with absence/or reduction in grazing activity created conducive environmental milieu for red tide outbreak. Dal Lake “red tide” drifted the bloom‐inoculum to other waters, including Lake Wular, where additional ecological niches were carved out, threatening the aesthetic value and biological diversity of Kashmir lakes. Ecological monitoring indicates frequent seasonal red tide occurrence in Dal Lake (including summer‐autumn event of 1998) which testifies its unabated eutrophication status. Further studies are needed on ecological adaptability and biogeographic distribution of this rare and unique red tide‐causing flagellate.