Diagnosis of a new species of neolithodes (Crustacea: Anomura: Lithodidae) from New Zealand (note)     

Elliot W. Dawson  J. C. Yaldwyn 《新西兰海洋与淡水研究杂志》2013,47(2):227-228

A new stone crab, Neolithodes brodiei sp.nov., known from an ovigerous female taken in 455 fm (832 m) on the Campbell Plateau, is characterised and distinguished from the five species previously recognised. It is morphologically close to the North Atlantic N. agassizii and the South African N. asperrimus.  相似文献   

The river continuum concept — reply to Barmuta and Lake     

M. J. Winterbourn 《新西兰海洋与淡水研究杂志》2013,47(2):229-231

Spectral analyses of water‐level oscillations in Wellington Harbour during the 1960 Chilean and 1964 Alaskan tsunamis are given. The results are used to define the periods for the three longest‐period characteristic oscillation modes. Some implications for future tsunamis are discussed.  相似文献   

Morphological characterization of cluster microforms     

K. B. STROM  A. N. PAPANICOLAOU 《Sedimentology》2008,55(1):137-153

A field study was conducted on two mountain streams in the Cascade Mountains of Washington State on the morphological characterization of cluster microforms. Morphological characterization of clusters is presented in terms of: (i) cluster shape; (ii) cluster geometric properties; and (iii) the spatial arrangement of clusters in the horizontal plane. Clusters were differentiated from other microtopography features such as reticulate structures and transverse ribs, and identified clusters were categorized by shape as being of pebble, line, comet, heap or ring type. The complex spatial arrangement of clusters at the sites was characterized by using a two‐dimensional correlation function, which allowed for measurement of the average cluster‐spacing properties. For the rivers examined, pebble‐shaped clusters were the most frequently observed cluster shape. Cluster geometric properties were found to be controlled by particles of the largest size fraction in the bed and the projected frontal width of the cluster – with cluster length being linearly related to cluster width for cluster width‐to‐height ratios <3·5. Results of the cluster‐spacing analysis suggest that cluster spacing increases with cluster size and decreases with local slope. Application of this principle to the available spacing data shows that cluster spacing λ scales with the ratio of S/d₀ such that λS/d₀ = constant, where S is the local slope and d₀ the diameter of the largest particle in the cluster.  相似文献   

陕北沙漠区地下工程交通竖井方案的选择          下载免费PDF全文

蒋改山  陈强  焦振华 《探矿工程》2010,37(9):64-66

＂涌沙＂是陕北沙漠区坑井工程普遍遇到的地质灾害问题,不同工程位置、不同岩土结构特征、不同水文地质条件下,井内涌沙的潜在危害迥异。研究竖井所在位置的地质条件,针对性地采取措施,避免竖井内涌沙是工程顺利竣工的关键。通过对已有工程事故的分析汇总,归纳出沙漠区可行的3种交通竖井方案及其适用的地质条件,并指出了每种方案在设计及施工过程中应引起高度重视的节点问题,具有一定的推广价值,可供同行借鉴。  相似文献   

矿井涌水量时间序列混沌特性的Kolmogorov熵判别          下载免费PDF全文

肖江  连生土  唐依民  张焕英 《地学前缘》2010,17(6):187-191

根据相空间重构理论和技术以及G-P算法,在嵌入维按等间隔m不断增加的情况下,在无标度区间内,作等斜率线性回归,利用最小二乘法得到6个典型矿区矿井涌水量时间序列的Kolmogorov熵。结果表明其具有混沌特性,从而可为确定矿区地下水系统特征、性质和矿井涌水量预测模式提供理论依据。  相似文献   

矿井涌水量计算的非稳定流解析法   总被引：1，自引：0，他引：1  

华解明 《中国煤炭地质》2010,(10):38-40

目前矿井涌水量预测普遍存在着评价方法简单、机械套用计算公式、或利用应用软件玩模拟游戏等现象,反而对非常适用的非稳定流解析法重视不够。根据非稳定流解析法公式的基本原理,对其在矿井涌水量预测方面的适用性进行了讨论,并以山西省霍州煤电集团公司某煤矿采区水文地质补充勘查报告矿井涌水量预测为例进行了计算,计算结果表明:非稳定流解析法的雅柯布(近似)公式对于煤层底板突水的矿井涌水量预测,较稳定流解析法和传统的类比外推法在理论上更适用,操作上更灵活;与数值法相比,其又具有较好的直观性。在实践中,该方法计算过程清晰,计算结果可靠,具有推广应用价值。  相似文献   

马坪岭煤矿地面岩溶塌陷分析   总被引：1，自引：0，他引：1  

唐志祥  张道勇  朱林英 《中国煤炭地质》2010,(2):28-32

与马坪岭煤矿毗邻的某军工企业厂区附近发生地面塌陷,严重影响了企业的正常生产。为此需对马坪岭煤矿地面岩溶塌陷进行分析。通过收集资料与实地调查,认为地面塌陷是由于附近煤矿、老窑开采引发突水,长期疏干排水以及大量的抽取地下水造成的。为了以后能安全顺利开采,以-50m标高为界,根据老窑分布、地层岩性、未来采空区的涌水量,将开采区划分为水文地质条件复杂区和中等区。其中预测复杂区最大涌水量为1 792m3/h,易引发地面塌陷,目前不宜开采;中等区最大涌水量253m3/h,不易引发地面塌陷。并根据矿区构造特点,提出了在断层附近采取帷幕注浆方式,以减少断层导水性的预防措施。  相似文献   

山东省苍山县沟西-西官庄铁矿沟西矿区水文地质特征及涌水量预测          下载免费PDF全文

朱昶  许锦亮  刘邦军  张立  马腾  宋帅良 《山东国土资源》2014,30(2):38-42

山东省苍山县沟西-西官庄地区赋存有隐伏的鞍山式低品位铁矿,矿区水文地质条件属于中等型。对勘探施工的51个地质孔全部进行了简易水文地质编录,9个水文地质孔进行分层抽水试验,查明了铁矿矿区水文地质条件,对矿床充水因素进行了分析,确定水文地质单元边界条件模型,采用承压—无压完整式巷道双边进水水平坑道计算公式,对坑道各水平涌水量预测。预测结果与相邻水文地质条件相似的开采矿山涌水量分析对比,基本与当地相邻矿山涌水量实际相符,能够为矿山开发利用提供地学依据。  相似文献