Application of turning bands technique to simulate values of copper ore deposit parameters in Rudna mine (Lubin-Sieroszowice region in SW part of Poland)

ABSTRACT

The turning bands simulation is a valuable and highly useful tool in solving various geological-mining, environmental and geological-engineering problems when it is essential to determine the uncertainty of the estimates of simulated values Z_s (realizations) and assess the risk. This paper presents an investigative methodology and the results of calculations connected with the use of conditional turning bands simulation and bundled indicator kriging, making it possible to analyse the risk at different levels of uncertainty in the solution of optimization of the exploitation problems encountered in the mining of the polymetallic copper ore deposits in the Lubin-Sieroszowice region (Foresudetic monocline, the SW part of Poland). Examples of the evaluation of simulated values Z_s and probability P average values Z* of the deposit parameters within the block located in the Rudna Mine (the block R-3) area are provided.     

Treating risk as relational on shore platforms and implications for public safety on microtidal rocky coasts

Natural Hazards - Drowning on rocky coasts is a problem with global significance, but it is a particularly acute issue in Australia where rocky coasts account for 19% of coastal drownings. The risk...     

Letšeng diamond mine,Lesotho: a variant of Kimberley-type pyroclastic kimberlite emplacement

The Letšeng Diamond Mine comprises two ~91 Ma kimberlite pipes. An update of the geology is presented based on the 2012–2017 detailed investigation of open pit exposures and all available drillcores which included mapping, logging and petrography. Each of the steep-sided volcanic pipes comprises a number of phases of kimberlite with contrasting diamond contents which were formed by the emplacement of at least four batches of mantle-derived magma. The resulting range of textures includes resedimented volcaniclastic kimberlite (RVK), Kimberley-type pyroclastic kimberlite (KPK), coherent kimberlite (CK) and minor amounts of hypabyssal kimberlite (HK). The pipes are compared with KPK occurrences from southern Africa and worldwide. Many features of the Letšeng pipes are similar to KPK infilled pipes particularly those of the widespread Cretaceous kimberlite province of southern Africa. The differences displayed at Letšeng compared to other large KPK pipe infills described from around the world are attributed to the marginal or melnoitic nature of the magma and the upper diatreme to crater setting of the Letšeng pipes, where processes become extrusive. It is concluded that the pipes comprise a variant of Kimberley-type pyroclastic kimberlite emplacement. The classification of many of the Letšeng rocks as KPK is important for developing the internal geology of the pipes as well as for predicting the distribution of diamonds within the bodies.

     

Status and future of laser scanning, synthetic aperture radar and hyperspectral remote sensing data for forest biomass assessment

This is a review of the latest developments in different fields of remote sensing for forest biomass mapping. The main fields of research within the last decade have focused on the use of small footprint airborne laser scanning systems, polarimetric synthetic radar interferometry and hyperspectral data. Parallel developments in the field of digital airborne camera systems, digital photogrammetry and very high resolution multispectral data have taken place and have also proven themselves suitable for forest mapping issues. Forest mapping is a wide field and a variety of forest parameters can be mapped or modelled based on remote sensing information alone or combined with field data. The most common information required about a forest is related to its wood production and environmental aspects. In this paper, we will focus on the potential of advanced remote sensing techniques to assess forest biomass. This information is especially required by the REDD (reducing of emission from avoided deforestation and degradation) process. For this reason, new types of remote sensing data such as fullwave laser scanning data, polarimetric radar interferometry (polarimetric systhetic aperture interferometry, PolInSAR) and hyperspectral data are the focus of the research. In recent times, a few state-of-the-art articles in the field of airborne laser scanning for forest applications have been published. The current paper will provide a state-of-the-art review of remote sensing with a particular focus on biomass estimation, including new findings with fullwave airborne laser scanning, hyperspectral and polarimetric synthetic aperture radar interferometry. A synthesis of the actual findings and an outline of future developments will be presented.     

Solar wind structure sources and periodicities of auroral electron power over three solar cycles

We assess the contributions of various types of solar wind structures (transients, coronal hole high-speed streams (HSS), and slow-speed wind) to hourly average auroral electron power (P_e). The time variation of the solar wind velocity (V_sw) and P_e are determined by HSS, which contribute ～47% to P_e and V_sw. Transients contribute ～42% of P_e in solar maxima, and ～6% in solar minimum. Cross-correlations of P_e with V_sw|B| for negative B_z are significant. P_e exhibits solar rotational periodicities similar to those for V_sw, with strong 7- and 9-day periodicities in 2005–2008 and equinox semiannual periodicities in 1995–1999.     

Coherence between lake ice cover, local climate and teleconnections (Lake Mendota, Wisconsin)

Ice duration has shortened and the ice-off date has become earlier for Lake Mendota from 1905 to 2000 as air temperatures have warmed and snowfall has increased. In addition, the ice record has cyclic components at inter-annual and inter-decadal scales. We examined the frequency domain relations between ice, local climate and the teleconnections, Southern Ocean Oscillation (SOI), Pacific Decadal Oscillation (PDO), North Atlantic Oscillation (NAO), and Northern Pacific Index (NP), through a three-tiered analysis of coherence. The coherence results provide evidence of linear relations between the three levels at inter-annual and inter-decadal frequencies. Of the three local climate variables analyzed, namely temperature, snowfall and snow depth, temperature is the variable that most significantly affects ice duration and ice-off date, at both inter-annual and inter-decadal frequencies. The most significant effect of teleconnections on local climate are the effects of PDO on snowfall and snow depth, and SOI on temperature, at inter-annual frequencies, and the effect of NAO on snowfall at inter-decadal frequencies. The teleconnections that most significantly affect ice-cover duration and ice-off date, particularly at inter-decadal frequencies, are the PDO and the NAO. The influence of PDO on ice-cover appears to be transmitted through temperature, while the influence of the NAO appears to be transmitted through temperature and snowfall. A cascading set of links between teleconnections, local climate, and lake ice explain some, but not all, of the dynamics in these time series.     

Calcified microbial mats date prehistoric canals—Radiocarbon assay of organic extracts from travertine

A methodology for radiocarbon dating of calcified microbial mats has been developed and successfully applied in establishing a preliminary chronology for the prehistoric carbonate-encrusted canals of the Tehuacán Valley of Puebla, Mexico. In contrast to traditional carbonate dating techniques, this method focuses on the organic carbon component of the calcareous sediments. This method is based on the assumptions that (1) the carbon being dated is derived from the organisms associated with travertine buildup on canals, (2) these organisms are incorporated into the travertine contemporaneous with calcite precipitation, and (3) this carbon is then sequestered from most subsequent contamination and secondary fractionation. Evidence supporting these assumptions includes δ¹³C values, cultural chronologies, and stratigraphic relationships consistent with expectations. © 1996 John Wiley & Sons, Inc.     

Storm Time Ionospheric-Tropospheric Dynamics: a Study Through Ionospheric and Lower Atmospheric Variability Features of High/Mid and Low Latitudes

Geomagnetism and Aeronomy - Geomagnetic storm is one of the major disturbances in Earth’s magnetosphere and its effect on ionosphere is a well studied area, yet there are a few aspects still...