Observations and analyses of floc size and floc settling velocity in coastal salt marsh of Luoyuan Bay, Fujian Province, China

In coastal environments, fine-grain sediments often aggregate into large and porous flocs. ElectroMagnetic Current Meters (EMCM) and Laser In Situ Scattering and Transmissometry (LISST-ST) have been deployed within a Spartina alterniflora marsh of the Luoyuan Bay in Fujian Province, China, to measure the current velocity, the floc size and the settling velocity between 15 and 22 January 2008. During the observations, the near-bed water was collected in order to obtain the suspended sediment concentration (SSC) and constituent grain size. Data show that: (1) the nearbed current velocities vary from 0.1 to 5.6 cm/s in the central Spartina alterniflora marsh and 0.1–12.5 cm/s at the edge; (2) the SSCs vary from 47 to 188 mg/dm 3 . The mean grain size of constituent grains varies from 7.0 to 9.6 μm, and the mean floc sizes (MFS) vary from 30.4 to 69.4 μm. The relationship between the mean floc size and settling velocity can be described as: w s =ad b , in which w s is the floc settling velocity (mm/s), a and b are coefficients. The floc settling velocity varies from 0.17 to 0.32 mm/s, with a mean value of 0.26 mm/s, and the floc settling velocity during the flood tide is higher than that during the ebb tide. The current velocity and the SSC are the main factors controlling the flocculation processes and the floc settling velocity.     

福建德化县九户林陶瓷土(瓷石)成矿地质条件及找矿方向

九户林陶瓷土(瓷石)矿床为碱长花岗岩脉型矿床,矿体赋存在晚白垩世碱长花岗岩体中,严格受张性断裂构造控制,矿体两侧具钾长石化带-纳长石化带-云英岩化带等蚀变分带,矿体与岩体、断裂构造组成了三位一体的成矿条件,属岩浆期后结晶分异作用形成的热液型矿床,成矿条件独特,晚白垩世碱长花岗岩(κργK2)岩体中,是该区瓷土(瓷石)找...     

Coenotypes in Submerged Paleoforests in the Qianhu Bay, Fujian Province

The paleoforest remains studied are distributed within a range of 18000 m^2 in the intertidal zone of the Qianhu Bay, Fujian Province. Eighty-nine ancient tree stumps can be clearly recognized in the paleoforest remains. Microscopic studies of 10 relatively low-carbonized stump samples definitely showed four species： Glyptostrobus pensUi （Staunt） Kouch, Schima superba Gardn., Cinnamomum Schaeffer, and Litsea Lam. The 14^C dating of some samples yielded the ages of 42560±350 to 〉43000 a B. P., corresponding to the late Late Pleistocene.     

福建龙海天马山-牛头山玄武岩中捕虏体和巨晶特征的研究

本文研究了天马山-牛头山新生代玄武岩中二辉橄榄岩和橄辉斜长岩捕虏体的岩石学、矿物学和地球化学等特征并论及碱性玄武岩中单斜辉石和歪长石巨晶。尖晶石二辉橄榄岩存在于碱性玄武岩和橄榄拉斑玄武岩中,由尖晶石、橄榄石、斜方辉石、铬透辉石等组成,与模拟地幔岩相比,具低的MgO含量和不相容元素Ti丰度而富集Co、Ni相容元素。尖晶石二辉橄榄岩具低的稀土总量和平缓的球粒陨石标准化稀土元素分配模式,形成于温度约1000℃、深度为50—80公里的上地幔。橄辉斜长岩具正堆积结构,Al_2O_3、CaO、∑REE和La/Yb明显高于二辉橄榄岩。但MgO含量远低于后者,反映两者成因的不一致性。普通辉石巨晶以富铝为特征,歪长石以富钙为特征。     

福建省地理教学研究会召开第三届代表大会暨学术年会

1994年11月，福建省教育学会地理教研会在福建省建阳市和武夷山市，召开第三届会员代表大会暨学术年会。与会代表70多人，交流学术论文100多篇。会议对九年义务教育大纲、教材和即将修订的高中大纲、教材进行了热烈研讨，     

福建前泥盆纪地壳演化的探讨兼论闽东基底性质

福建陆壳起源于太古代，在其发展演化过程中具多期、多阶段的特点，本文将福建前泥盆纪地壳演化划分为太古代闽西南古陆(核)形成、早-中元代闽北古陆边缘活动增生和晚元古-早古生代板内裂谷活动，并分别阐述各阶段的演化特点，对闽东基底性质亦作一定的探讨。     

福建西部魏坊地区的奥陶系

<正> 福建境内魏坊地区的奥陶系出露最完整、研究也最详细,1931年王绍文于魏坊之西十余公里的罗峰溪村一带创立“罗峰溪千枚岩”,罗峰溪群一名系指整合于震旦系之上、不整合于晚泥盆世粗碎屑岩之下的一套厚度巨大的浅变质砂、泥、硅质复理石建造。时代统归下古生界。福建省区调队将本套地层划分成四个群五个岩性段,创建东坑口群、魏坊群     

闽台铲状活动断裂

福建台湾大型铲状活动断裂系在深部(深5—100km)构成一系列向东倾斜、倾角为4°—10°的滑脱面,在近地表利用老断层的重新活动,形成NNE与NW向网格交叉的高角度断层。活动断裂系的地震能量释放主要集中在台湾东部。推断现代构造应力场的最大主压应力方向是NW—SE向,缓倾斜、向西撒开呈扇状特征。断裂系中各断裂的滑动速率不同,东大西小。