scholarly journals Cajamarca: Mapping (Post)Mining Palimpsests of the Peruvian Andes

2020 ◽  
Vol 5 (2) ◽  
pp. 172-190
Author(s):  
Margarita Macera ◽  
Bruno De Meulder ◽  
Kelly Shannon

Mining, in addition to other human activities and natural phenomena, has repeatedly reshaped the landscapes of the Peruvian Andes. Long-standing, significantly modified and new Andean landscapes have resulted in a complex reading of the ‘land as palimpsest’ (Corboz, 1983). In recent decades, large-scale modern mining has disturbed headwater landscapes and broader Andean ecologies, as exemplified in Cajamarca’s gold mines. This article critically reads past and present spatial transformations induced by gold mining in the headwaters of the Cajamarca Basin. Through archival documentation, fieldwork and interpretative cartography, it analyses the large-scale surface mining operations in Cajamarca from 1993 to 2020, as well as their impact on downstream rural and urban ecologies. A cross-scalar mapping investigation discloses the spatial-ecological outcomes of twenty-seven years of mining (and closure) operational procedures. As a conclusion of the palimpsest reading, a design-research question is posed as to how Cajamarca’s post-mining landscapes can be opportunely premeditated. It hypothesizes that, already during exploitation, the post-mining landscapes can be consciously constructed by an intelligent manipulation of mining procedures and create a layer of the territory that is more robust. Environmental reconstruction after mining closure recreates a pseudo-natural environment that supposedly erases the traces of mining and restores natural condition—literally back to nature, with no cultural trace. In this regard, reconstruction is merely theoretical since the repairing to a natural state would mean no palimpsests. However, despite the most imaginative and ecological repair, the territory remains a mega palimpsest, cruelly violated and disrupted. Therefore, at best, the proposition can be to build a cultural, consciously conceived and tailored post-mining landscape, merging mining and post-mining landscape construction into one movement, where the remaining (palimpsest) is part-and-parcel of the newly constructed.

2016 ◽  
Vol 8 (1) ◽  
Author(s):  
Chrysanthos Steiakakis ◽  
Zacharias Agioutantis ◽  
Evangelia Apostolou ◽  
Georgia Papavgeri ◽  
Achilles Tripolitsiotis

AbstractThe geotechnical challenges for safe slope design in large scale surface mining operations are enormous. Sometimes one degree of slope inclination can significantly reduce the overburden to ore ratio and therefore dramatically improve the economics of the operation, while large scale slope failures may have a significant impact on human lives. Furthermore, adverse weather conditions, such as high precipitation rates, may unfavorably affect the already delicate balance between operations and safety. Geotechnical, weather and production parameters should be systematically monitored and evaluated in order to safely operate such pits. Appropriate data management, processing and storage are critical to ensure timely and informed decisions.This paper presents an integrated data management system which was developed over a number of years as well as the advantages through a specific application. The presented case study illustrates how the high production slopes of a mine that exceed depths of 100–120 m were successfully mined with an average displacement rate of 10– 20 mm/day, approaching an almost slow to moderate landslide velocity. Monitoring data of the past four years are included in the database and can be analyzed to produce valuable results. Time-series data correlations of movements, precipitation records, etc. are evaluated and presented in this case study. The results can be used to successfully manage mine operations and ensure the safety of the mine and the workforce.


Author(s):  
A.F. Klebanov ◽  
M.V. Kadochnikov ◽  
V.V. Ulitin ◽  
D.N. Sizemov

The article addresses the issues of ensuring safe operation of mining equipment in surface mining. It describes the main factors and situations that pose a high risk to human life and health. The most dangerous incidents are shown to be related to limited visibility and blind spots for operators of mining equipment, which can result in collisions and personnel run over. The main technologies and specific solutions used to design collision avoidance systems are described and their general comparison is provided. A particular focus is placed on monitoring the health of employees at their workplace by means of portable personal devices that promptly inform the dispatcher of emergency situations. General technical requirements are formulated for designing of the system to prevent equipment collisions and personnel run over in surface mining operations. The paper emphasizes the importance of introducing a multifunctional safety system in surface mines in order to minimise the possibility of incidents and accidents throughout the entire production cycle.


2018 ◽  
Vol 138 (2/2018) ◽  
pp. 84-89
Author(s):  
K.Yu. Anistratov ◽  
T.V. Donchenko ◽  
P.I. Opanasenko ◽  
I.B. Strogiy

SLEEP ◽  
2021 ◽  
Author(s):  
Dorothee Fischer ◽  
Elizabeth B Klerman ◽  
Andrew J K Phillips

Abstract Study Objectives Sleep regularity predicts many health-related outcomes. Currently, however, there is no systematic approach to measuring sleep regularity. Traditionally, metrics have assessed deviations in sleep patterns from an individual’s average. Traditional metrics include intra-individual standard deviation (StDev), Interdaily Stability (IS), and Social Jet Lag (SJL). Two metrics were recently proposed that instead measure variability between consecutive days: Composite Phase Deviation (CPD) and Sleep Regularity Index (SRI). Using large-scale simulations, we investigated the theoretical properties of these five metrics. Methods Multiple sleep-wake patterns were systematically simulated, including variability in daily sleep timing and/or duration. Average estimates and 95% confidence intervals were calculated for six scenarios that affect measurement of sleep regularity: ‘scrambling’ the order of days; daily vs. weekly variation; naps; awakenings; ‘all-nighters’; and length of study. Results SJL measured weekly but not daily changes. Scrambling did not affect StDev or IS, but did affect CPD and SRI; these metrics, therefore, measure sleep regularity on multi-day and day-to-day timescales, respectively. StDev and CPD did not capture sleep fragmentation. IS and SRI behaved similarly in response to naps and awakenings but differed markedly for all-nighters. StDev and IS required over a week of sleep-wake data for unbiased estimates, whereas CPD and SRI required larger sample sizes to detect group differences. Conclusions Deciding which sleep regularity metric is most appropriate for a given study depends on a combination of the type of data gathered, the study length and sample size, and which aspects of sleep regularity are most pertinent to the research question.


2003 ◽  
Vol 14 (1) ◽  
pp. 59-67
Author(s):  
Adepo Jepson Olumide ◽  
Ayodele Charles Oludare ◽  
Balogun Olufemi

Coal, a solid fuel in its natural state has been identified as one of the world's major fossil fuels. It is a compact, stratified mass of mummified plant debris interspersed with smaller amounts of inorganic matter buried in sedimentary rocks. The use of coal as an energy source can be dated back to the prehistoric times. Methane is associated with many if not all coal seams, and is the dreaded “fire damp” responsible for many pit explosions. Coal mines are designed to vent as much methane as possible. It is present in the pores of coal under pressure, released during mining operations and can be extracted through vertical well bores. This paper highlights the fact that pipeline- quality methane can be extracted economically from coal seems before and during underground mining operations. The stimulation method involves hydraulic fracturing of the coal seam by using water, sand and, a gelling agent in a staged and alternating sand/and no sand sequence. The purpose is to create new fractures in the coal seam(s). The cleating of the coal helps to determine the flow characteristics of the coal formation and is vital in the initial productivity of a coal-methane well. The simple calculation of gas-in-place is achieved by multiplying the gas content of the coal by net coal thickness, the density, and the aerial extent of the drainage. The method is claimed to be suitable for use in Nigeria and potential sites for coal bed methane extraction in Nigeria are identified.


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