The tectonic regime in Italy inferred from borehole breakout data

In Italy, the horizontal stress directions are well constrained in many regions, but the tectonic regime is not well known because the stress magnitudes are unknown. Our intention is to improve the knowledge of crustal stress in Italy, both at shallow depth and in low seismicity areas. Therefore, we inferred the tectonic regime from the comparison between the depth of breakout occurrence and the physical properties of the rocks in 20 boreholes. The critical value of the maximum horizontal stress, for which the effective tangential stress at the borehole wall overcomes the rock strength to form breakouts, could be computed from rock strength and density. Comparing the theoretical stress distributions for different tectonic regimes with the depth distribution of breakout occurrence, it is possible to infer the tectonic regime that fits best to the breakout depth distribution. We investigated boreholes up to 6 km deep located in different tectonic environments over the Italian peninsula: the Po Plain, the Apenninic chain, the Adriatic foredeep and the Tyrrhenian Quaternary volcanic region. These wells are characterised by breakout data of good quality (A, B and C, according to World Stress Map quality ranking system). The results are in general agreement with the style of faulting derived from earthquake focal mechanisms and other stress indicators. Our results show a predominance of a normal faulting (NF) regime in the inner Apennines and both normal faulting and strike–slip faulting (SS) style in the surrounding regions, possibly also associated with changes in the tectonic regime with depth.     

Geothermal Regime of Meso-Cenozoic Basins and Their Tectonic Background in East China

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多功能水文频率分析计算软件的研制和应用

介绍了多功能水文频率分析计算软件的设计及功能扩充，尤其是增加了采用鼠标拉动曲线直接屏幕适线的功能。本软件在生产实践中，获得了较好的应用效果，不仅功能多，而且实用方便。     

多年冻土区路桥过渡段的一种新结构

The design of roadbed-abutment transition part is always a challenging problem in transportation engineering, especially in permafrost distribution zone. A new type of roadbed-abutment transition part on permafrost was presented, and long-term observation was conducted for the deformation and the thermal regime of a roadbed-abutment transition part in the constructing Qinghai-Tibet Railway. In this paper, a new structure was presented and the observed settlements both in the subgrade and the base and its dependency with the thermal regime (permafrost table) were analyzed. In conclusion the roadbed-a-butment transition method for permafrost distribution zone was evaluated.     

A patch hierarchy approach to modeling surface and subsurface hydrology in complex flood‐plain environments

Geomorphology interacts with surface‐ and ground‐water hydrology across multiple spatial scales. Nonetheless, hydrologic and hydrogeologic models are most commonly implemented at a single spatial scale. Using an existing hydrogeologic computer model, we implemented a simple hierarchical approach to modeling surface‐ and ground‐water hydrology in a complex geomorphic setting. We parameterized the model to simulate ground‐ and surface‐water ?ow patterns through a hierarchical, three‐dimensional, quantitative representation of an anabranched montane alluvial ?ood plain (the Nyack Flood Plain, Middle Fork Flathead River, Montana, USA). Comparison of model results to ?eld data showed that the model provided reasonable representations of spatial patterns of aquifer recharge and discharge, temporal patterns of ?ood‐water storage on the ?ood plain, and rates of ground‐water movement from the main river channel into a large lateral spring channel on the ?ood plain, and water table elevation in the alluvial aquifer. These results suggest that a hierarchical approach to modeling ground‐ and surface‐water hydrology can reproduce realistic patterns of surface‐ and ground‐water ?ux on alluvial ?ood plains, and therefore should provide an excellent ‘quantitative laboratory’ for studying complex interactions between geomorphology and hydrology at and across multiple spatial scales. Copyright © 2004 John Wiley & Sons, Ltd.     

长白山天池火山地质学研究的若干进展与灾害分析

通过以减轻火山灾害为目的的天池火山锥体顶部地区地质填图工作，发现了天池火山锥体附近不同期次火山泥石流，部分火山泥石流显示的高温定位特征指示了其与千年大喷发的成因联系。这些火山泥石流构成了严重的火山泥石流灾害，天池火山锥体近顶部大型滑坡体的发现则指示了天池火山另一种重要的灾害类型。滑坡体堆积物结构上可分为3种类型。天池火山千年大喷发时不同成分与物性的岩浆混合作用十分发育，指示了天池火山喷发前不同岩浆批的混合与共喷发机理。本文还论述了天池火山近代历史记录喷发物的分布与鉴别特征。     

第二松花江流域水电厂综合中长期水文预报的分析研究

基于对第二松花江流域上游小山、松山、两江水电站中长期水文预报研究成果，论述了综合中长期水文预报的研究思路和定性预报、定量预报的分析研究方法。该研究通过2002年实践检验，具有较高的预报精度。     

Dynamics of an active rock glacier (Ötztal Alps, Austria)

The rock glacier Innere Ölgrube, located in a small side valley of the Kauner Valley (Ötztal Alps, Austria), consists of two separate, tongue-shaped rock glaciers lying next to each other. Investigations indicate that both rock glaciers contain a core of massive ice. During winter, the temperature at the base of the snow cover (BTS) is significantly lower at the active rock glacier than on permafrost-free ground adjacent to the rock glacier. Discharge is characterized by strong seasonal and diurnal variations, and is strongly controlled by the local weather conditions. Water temperature of the rock glacier springs remains constantly low, mostly below 1°C during the whole melt season. The morphology of the rock glaciers and the presence of meltwater lakes in their rooting zones as well as the high surface flow velocities of >1 m/yr point to a glacial origin. The northern rock glacier, which is bounded by lateral moraines, evolved from the debris-covered tongue of a small glacier of the Little Ice Age with its last highstand around A.D. 1850. Due to the global warming in the following decades, the upper parts of the steep and debris-free ice glacier melted, whereas the debris-covered glacier tongue transformed into an active rock glacier. Due to this evolution and due to the downslope movement, the northern rock glacier, although still active, at present is cut off from its ice and debris supply. The southern rock glacier has developed approximately during the same period from a debris-covered cirque glacier at the foot of the Wannetspitze massif.     

合理设计岩屑规程保证正常钻进条件——金刚石钻进技术专题之一

论述了正常钻进的条件，提出了合理岩屑规程是保证正常钻进的关键和设计钻头的主要依据之一，讨论了岩屑规程与金刚石钻头唇面工作状态、孔底表面粗糙度和岩屑粒度的关系，提出了相应的建议。