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1.
Linear discriminant analysis to describe the relationship between rainfall and landslides in Bogotá, Colombia 总被引：1，自引：0，他引：1
Alfonso Mariano Ramos-Cañón Luis Felipe Prada-Sarmiento Mario Germán Trujillo-Vela Juan Pablo Macías Ana Carolina Santos-R 《Landslides》2016,13(4):671-681
Bogotá is located in the central Andean region of Colombia, which is frequently affected by landslide processes. These processes are mostly triggered during the rainy season in the city. This fact remarks the importance of determining what rain-derived parameters (e.g. intensity, antecedent rain, daily rain) are better related with the occurrence of landslides. For this purpose, the linear discriminant analysis (LDA), a technique derived from multivariate statistics, was used. The application of this type of analysis led to obtain simple mathematical functions that represent the probability of occurrence of landslides in Bogotá. The functions also allow to identify the most relevant variables derived from records of rainfall linked to the generation of landslides. A proof of concept using the proposed methodology was done using historic rainfall data from a 9-km2 area of homogenous climatology and geomorphology in the south part of Bogotá. Landslides needed to be grouped for the LDA. Each one of these grouping categories represents landslides that occurred in similar geomorphologic conditions. Another set of events with no landslides was generated synthetically. Results of the proof of concept show that rainfall parameters such as normalized rainfall intensity I MAP, normalized daily rainfall R MAP and rainy-days normal RDN have the best statistical correlation with the landslides observed in the zone of analysis. 相似文献
2.
Shinro Abe Dinh Van Tien Do Ngoc Ha Takashi Hoshide Tadashi Nishitani Toyohiko Miyagi 《Landslides》2018,15(8):1675-1689
Many landslides occur every year during heavy rains at the Hai Van Pass and surrounding area in central Vietnam, where granitic rocks are distributed. As is common in granite areas, these landslides often occur as small-scale flow-type and slump-type landslides. However, several horseshoe-shaped loose slopes of widths and lengths of 500 to 800 m, which incorporate these landslides, are observed on slopes across the area. These topographies resemble those formed by past and present large-scale landslides. The presence of such a topography and the repeated occurrences of landslides within this topography are rare in granite areas, where shallow flow-type landslides are generally frequent. To understand the mechanism causing the landslides in the Hai Van region, and as a support for future risk assessment, the factors and processes leading to the formation of such a topography and their relationship with these landslides must be identified and assessed. This study investigated the history of past landslide movement in the Hai Van Pass and surrounding area through observations of drill cores and outcrops, and analysis of the direction of remanent magnetism in the granitic rocks. Mineral compositions, cracks, degrees of weathering, and topographic shapes of the granitic rocks and their relationship to the landslides occurring today were also investigated. The results of the study reveal no variation in the direction of remanent magnetism in the granitic rocks in the region that would indicate disturbance of the ground due to a past large-scale landslide. No evidence of such an event could also be found both in the drill cores and the rock outcrops. Further, results of the analysis of cracks and weathering pattern confirm that the topography of the region is affected by the weathering of the granitic rocks that progresses in concentric circles of various sizes. Thus, it can be concluded that these topographies were not formed by a singular large-scale landslide of the past, but rather by a composite of relatively shallow landslides occurring on the slope of dome structures unique to granite areas, which are formed by differential weathering and denudation regulated by cracks. 相似文献
3.
Do landslides follow landslides? Insights in path dependency from a multi-temporal landslide inventory 总被引：1，自引：0，他引：1
Jalal Samia Arnaud Temme Arnold Bregt Jakob Wallinga Fausto Guzzetti Francesca Ardizzone Mauro Rossi 《Landslides》2017,14(2):547-558
Landslides are a major category of natural disasters, causing loss of lives, livelihoods and property. The critical roles played by triggering (such as extreme rainfall and earthquakes), and intrinsic factors (such as slope steepness, soil properties and lithology) have previously successfully been recognized and quantified using a variety of qualitative, quantitative and hybrid methods in a wide range of study sites. However, available data typically do not allow to investigate the effect that earlier landslides have on intrinsic factors and hence on follow-up landslides. Therefore, existing methods cannot account for the potentially complex susceptibility changes caused by landslide events. In this study, we used a substantially different alternative approach to shed light on the potential effect of earlier landslides using a multi-temporal dataset of landslide occurrence containing 17 time slices. Spatial overlap and the time interval between landslides play key roles in our work. We quantified the degree to which landslides preferentially occur in locations where landslides occurred previously, how long such an effect is noticeable, and how landslides are spatially associated over time. We also investigated whether overlap with previous landslides causes differences in landslide geometric properties. We found that overlap among landslides demonstrates a clear legacy effect (path dependency) that has influence on the landslide affected area. Landslides appear to cause greater susceptibility for follow-up landslides over a period of about 10 years. Follow-up landslides are on average larger and rounder than landslides that do not follow earlier slides. The effect of earlier landslides on follow-up landslides has implications for understanding of the landslides evolution and the assessment of landslide susceptibility. 相似文献
4.
Graciano P. Yumul Jr. Nathaniel T. Servando Leilanie O. Suerte Mae Y. Magarzo Leo V. V. Juguan Carla B. Dimalanta 《Natural Hazards》2012,62(3):827-840
An unusual amount of precipitation fell in Panay island during the passage of Typhoon Fengshen (local name: Typhoon Frank) in June 2008. The voluminous amount of rain is attributed to the interaction of the tropical cyclone and southwest monsoon as the latter was enhanced by the former during its passage across central Philippines. Ground and aerial surveys were conducted to document the extensive flooding and landslides that occurred in the island. Artificial damming of rivers followed by breaching resulted to flooding, whereas steep slopes, fractured lithologies and intense precipitation were recognized to have led to the occurrence of landslides. These natural hazards and their causes are presented to contribute to our understanding of how weather systems evolve and what the corresponding effects are on the ground. This, hopefully, can provide significant inputs in improving disaster risk reduction and preparedness programs. 相似文献
5.
The Iwate–Miyagi Nairiku Earthquake in 2008, whose seismic intensity was M. 7.2 in Japan Meteorological Agency (JMA) scale,
induced innumerable landslides on the southern flank of Mt. Kurikoma volcano allocated along the Ou Backbone Range in Northeast
Japan. Most landslides are detected in a hanging wall side of the seismic fault. Those landslides are classified into five
types: deep-seated slide, debris slide, shallow debris slide, secondary shallow debris slide, and debris flow. Most common
landslide types induced by the earthquake are shallow debris slides and subsequent debris flows. They are intensively distributed
along steep gorges incising a volcanic skirt of Mt. Kurikoma, consisting of welded ignimbrite of the Pleistocene age. Debris
flows are also distributed even along gentle river floors in the southern lower flank of the volcano. The area of densely
distributed debris slides, shallow debris slides, and debris flows is concordant with that of severe seismic tremor. Thus,
genetic processes of landslides induced by the Iwate–Miyagi Nairiku Earthquake in 2008 are attributed to multiple causative
factors such as geology, topography, and seismic force. 相似文献
6.
7.
Baator Has Tomoyuki Noro Kiyoteru Maruyama Akira Nakamura Kiichiro Ogawa Satoshi Onoda 《Landslides》2012,9(4):539-546
The northern Nagano Prefecture earthquake, MJMA?6.7 (Mw?6.2), which is inferred to have been triggered by the huge (Mw?9.0) March 11, 2011 Tohoku earthquake, occurred on March 12, 2011, in northern Nagano Prefecture, an area in Japan famous for heavy snowfall. A large number of landslides were triggered by the 12 March earthquake, and it caused building damage in the area of the epicenter. To clarify characteristics of the distribution and dynamic behavior of these landslides, we analyzed aerial photographs and conducted field surveys in and around the epicentral area. Large-scale landslides with long distance run-outs are a remarkable characteristic of the landslides induced by this earthquake. The long travel distance is considered to be related to the thick snowpack at the time the earthquake occurred. Moderate scale deep-seated landslides and shallow landslides were also observed in the study area. Based on an analysis of landslides with the active fault on which the earthquake is believed to have occurred, most of these landslides were distributed on the hanging wall of the active fault, within a distance of 12?km from the fault. 相似文献
8.
Antonio Santo Giuseppe Di Crescenzo Giovanni Forte Raffaele Papa Marianna Pirone Gianfranco Urciuoli 《Landslides》2018,15(1):63-82
In the last 20 years, major efforts have been made to investigate shallow flow-type landslides. Such phenomena are usually rainfall-induced and in the geological context of Campania (Southern Italy) occur in pyroclastic soils resting on steep slopes mainly constituted by carbonate or volcanic bedrock and by flysch deposits. They are generally complex landslides with an early soil slide and a subsequent flow evolution. In this paper, a database of flowslides occurring in recent years within the flysch deposits of Avellino (Campanian Apennines) is first discussed and then the case study of Bosco de’ Preti landslide on March 4, 2005, is described. The geological and geotechnical characteristics of the soils involved are described and the monitoring of the groundwater heads collected over 1 year from June 2005 to June 2006 is also shown. The last part of the paper illustrates the results of numerical modelling of the landslide triggering to gain insights into such phenomena. Slope stability analyses are preceded by hydrological modelling of the slope based on the monitoring data. Numerical analysis demonstrated that the rainfall during the 2 months preceding the event was able to fully saturate the pyroclastic cover and to establish positive pore water pressure at the depth of the surface of rupture, a soil condition never witnessed in carbonatic contexts. Hence, a combination of antecedent (predisposing factors) and single rainfall events (triggering factors) led to slope failure, as usually happens in pyroclastic soils in carbonatic and volcanic contexts. Finally, analysis of the historical landslides together with detailed investigation of the Bosco de’ Preti case study permitted comparison between flow-type landslides in pyroclastic soils on carbonatic/volcanic bedrock and those on flysch. 相似文献
9.
Landslides as secondary seismic effects are causing some patterns of soil failure that are often considered among the most destructive ones. In fact, the impact from triggered landslides has sometimes exceeded damage directly related to strong shaking and fault rupture. The objective of this research study is landslide hazard and risk assessment considering different water saturation and earthquake scenarios, for a selected area in a sub-urban hilly part of Skopje—the capital of Macedonia. The final product is represented by digital maps of expected permanent displacements for a defined earthquake scenario, in different water saturation conditions of the instable soil layer. Qualitative landslide risk assessment is performed taking into consideration the exposure map of the habitants and local road of the area. As to the target area, it can be concluded that it has the potential for instability that, under certain scenarios, could result in economic and social damage (vulnerability of individual houses, vulnerability of infrastructure and alike). The results from this study referring to potentially affected population and infrastructure present solid base for preventive mitigation activities for reducing the consequences of geotechnical hazards in Skopje City associated with earthquakes. 相似文献
10.
Mountain landslide has been an environmental geological problem and occurs frequently in China, especially in the karst region
of Guizhou Province, Southwest China. The data of karst mountain landslide are collected and analysed, which occurred in the
period of 1940–2002. The collection includes 321 events in the karst region of Guizhou Province. The characteristics of mountain
landslides may be classified as two types, namely natural mountain landslides (287 events) and the other induced by human
activities (34 events). The results indicate that natural mountain landslide causes especially high damage and is still the
main type of natural hazard in the study area owing to the extremely fragile karst geological environment. 相似文献
11.
Brian Gulson Karen Mizon Michael Korsch Honway Louie Michael Wu Jenny Stauber J. Michael Davis Alan Taylor 《中国地球化学学报》2006,25(B08):62-62
This is a 4-year longitudinal study to evaluate changes to the environment and exposure of young children associated with the introduction of methylcyclopentadienyl manganese tricarbonyl （MMT） into Australia in 2000. The cohort includes 57 females and 56 males; age range of 0.29 to 3.9 years. Samples are collected every 6 months from children in residences located at varying distances from major traffic thoroughfares in Sydney. Environmental samples： air, house and day care dustfall, soil, dust sweepings and gasoline. Samples from children： blood, urine, handwipes prior to and after playing outdoors, and a 6-day duplicate diet. All samples are analyzed for a suite of 20 elements using ICP-MS. Results are presented for the first three 6-month sampling periods for Pb and Mn. For dustfall accumulation, there was no significant change over the 3 sampling periods （time） for Pb or Mn, and a positive relationship between ‘traffic exposure＇ （traffic volume and proximity to the road） and Pb but not Mn. For handwipes, Pb and Mn in wipes taken from children after playing outdoors were usually significantly greater than for wipes taken prior to playing. There was no significant association between Pb or Mn in handwipes with traffic exposure. Dustfall accumulation was a significant predictor for Pb in the handwipes, and dust sweepings were a significant predictor of Mn in handwipes. 相似文献
12.
Liu Xiaoliang Chen Congyun Yang Xuezeng Yang Sen Zhang Jiongfei Gao Yuhua Shenyang Institute of Geology Mineral Resources Chinese Academy of Geological Sciences Shenyang Liaoning Sun Sheping 《《地质学报》英文版》1992,66(4):427-442
The Ordovician Changtu Fauna is recently discovered in the Xia' ertai and Hulan Groups in northernLiaoning-central Jilin. The fauna, containing 10 genera and 14 species (including 3 new genera, 9 new speciesand an unidentified species), is closely related in evolution with the Early Cambrian Qinghezhen Fauna. Thediscovery of this fauna is significant to the study on the age of the strata, Ordovician biostratigraphy and geo-logical evolution of the tectonostratigraphical terrane on the northern margin of the Sino-Korean plate. 相似文献
13.
ZHANG Kang WANG Darui Exploration Production Research Institute China Petroleum Chemical Corporation 《《地质学报》英文版》2004,78(3)
Almost all the oil and gas reservoirs developed in marine sedimentary strata of China have undergone processes of multi-phase reservoir formation and later modification. The irregular reservoirs are classified into three types as the Naxi, Tahe and Renqiu ones, increasing successively in the development degree of karstificated pores and fissures and the connection degree of independent reservoirs. In these reservoirs, the unity in the fluid feature, pressure and oil-gas-water interface also increases successively from the Naxi to the Renqiu type. The main body of Ordovician reservoirs of the Tahe Oilfield in the Tarim Basin is a network pool rather than a stratified, massive, stratigraphically-unconformed or weathering-crust one. The fluid nature of oil, gas and water, the interface positions and the pressures, as well as the dynamic conditions of fluids within the reservoirs during the production are all different from those in stratified or massive oil and gas reservoirs. Carbonates in the Akekule upli 相似文献
14.
ZHANG Kang WANG Darui Exploration Production Research Institute China Petroleum Chemical Corporation 《《地质学报》英文版》2004,78(3)
Almost all the oil and gas reservoirs developed in marine sedimentary strata of China have undergone processes of multi-phase reservoir formation and later modification. The irregular reservoirs are classified into three types as the Naxi, Tahe and Renqiu ones, increasing successively in the development degree of karstificated pores and fissures and the connection degree of independent reservoirs. In these reservoirs, the unity in the fluid feature, pressure and oil-gas-water interface also increases successively from the Naxi to the Renqiu type. The main body of Ordovician reservoirs of the Tahe Oilfield in the Tarim Basin is a network pool rather than a stratified, massive, stratigraphically-unconformed or weathering-crust one. The fluid nature of oil, gas and water, the interface positions and the pressures, as well as the dynamic conditions of fluids within the reservoirs during the production are all different from those in stratified or massive oil and gas reservoirs. Carbonates in the Akekule upli 相似文献
15.
16.
The capital city of Honduras, Tegucigalpa, suffers from the occurrence of destructive landslides on a yearly basis. During the rainy season, damages to infrastructure as well as injuries, casualties and homeless individuals resulting from landslides are reported in the press. This paper presents the development of a database for rainfall-induced landslides for the period 1980–2005, based on the news reported by two local newspapers. The editions comprehended during the study period have been scrutinized, and articles focusing on landslides, tropical storms, hurricanes, floods and vulnerability of the city have been collected. The interpretation of these archives has allowed the compilation of valuable data of approximately 400 landslides. The analyses of monthly and annual precipitation during the study period show how extreme rainfall events like Hurricane Mitch in October of 1998 have significantly contributed to the initiation of landslides. In addition, the assessment of the slums and neighborhoods affected by landslides during the study period reveals an evident link between the social and physical vulnerability of Tegucigalpa. In order to estimate the reliability of this press-based database, the set of landslides that have been reported as a result of Hurricane Mitch in the press archives has been compared with two inventories based on the interpretation of aerial photographs taken in 1999 and 2001. It is shown that the analysis of the landslide damage left after the hurricane can be enriched with the detailed temporal data provided in the archives and the precise location of these events determined by the aerial photographs. Despite the difficulties faced in the compilation of this database, a good comprehension of the temporal and spatial distribution of landslides in Tegucigalpa has been achieved. 相似文献
17.
Fan Jian-Jun Li Cai Wang Ming Xie Chao-Ming 《International Journal of Earth Sciences》2018,107(1):231-249
International Journal of Earth Sciences - When and how the Bangong–Nujiang Tethyan Ocean closed is a highly controversial subject. In this paper, we present a detailed study and review of the... 相似文献
18.
X. Chris Le Xiufen LU Meiling LU Nicole Orr Zhongwen WANG Chungang YUAN 《中国地球化学学报》2006,25(B08):77-78
Arsenic is the 20th most abundant element in the Earth crust. Humans are exposed to naturally occurring and anthropogenic sources of arsenic compounds in the environment. A wide variety of adverse health effects have been attributed to chronic exposure to high levels of arsenic. More than two-dozen arsenic compounds （species） are present in the environment and in biological systems. The various arsenic species have dramatically different behavior and toxicity. This presentation briefly describes arsenic speciation analysis, human exposure to and metabolism of arsenic species. Environmental issues on arsenic in Canada are briefly discussed. These include （1） the arsenic waste left from previous gold mining and smelting activities; （2） the domestic use of wood treated with chromated copper arsenate; and （3） use of well water as the source of drinking water by approximately one third of the Canadian population. 相似文献
19.
The results of synchronous measurements of temperature variations in a near-bottom thermocline, as well as microdeformations
of the Earth’s crust and atmospheric pressure pulsing, recorded on-shore with the help of a laser strainmeter and laser nanobarograph,
are presented. A string containing 20 thermosensors spaced at 0.5 m was used; it was placed by an anchored buoy in a place
with 21-m depth and 500 m away from the shore. A good correlation between microdeformations and atmospheric pressure variations
was observed for periods longer than 6 h. Quantitative estimates and spectral analysis via the Gilbert-Huang method for investigation
of nonstationary and nonlinear processes lead to the conclusion that, on temporal scales from tidal to several minutes, the
predominant way of formation of microdeformations in the Earth’s crust can be breaking of internal waves in a thermocline
that leads to shallow water (i.e., in the zone of “internal breakers”). 相似文献
20.
Erik Askov Mousing Thorbjørn Joest Andersen Marianne Ellegaard 《Estuaries and Coasts》2013,36(6):1206-1218
Changes in total abundance and in species composition of phytoplankton in the last 150 years in the southern Black Sea were investigated through a paleoecological study of two sediment cores. The results show changes in the species composition and a marked increase in total abundance of siliceous protists after around 1960. In core 22 (42°13.534′ N/36°29.555′ E), the dominating species before 1960 were Cyclotella choctawhatcheeana and Thalassiosira oestrupii. In core 25 (42°6.212′ N/36°37.460′ E), the dominating species before 1960 were T. oestrupii, Cyclotella meneghiniana, C. choctawhatcheeana, and Pseudosolenia cf. calcar-avis. Core 22 was located in closer proximity to the rim current than core 25, and the differences in total abundance between the cores could be related to differences in local nutrient loading prior to 1960. After around 1960, both cores changed to a community dominated by C. choctawhatcheeana. The changes in total abundance and species composition after around 1960 could be related to the increased nutrient loading from the Danube River into the rim current after the late 1960s. The results also showed changes in both total abundance and in species composition of dinoflagellate cysts. The dominating dinoflagellate cysts recorded were Lingulodinium polyedrum, Polykrikos schwartzii, and Spiniferites spp. 相似文献