RESEARCH OF A LATERAL REAMER BIT FOR DIGGING PLANTING HOLE IN ROCKY ABANDONED MINE AREA

In the abandoned mine area with Karst landform in China, soils are few and thin but rocks are common, traditional planting hole diggers are unequal to work in rocks for vegetation restoration. A reamer bit with variable lateral drilling radius was designed based on the PDC (polycrystalline diamond compact) bit technology and metamorphic mechanism. Two lateral camber blades with PDC teeth were installed inside the bit body, a screw mechanism was employed as the actuation and a spatial double triangle mechanism was taken for the transmission. The curve of the camber blade was specially defined thus the reaming load was decentralized to 85.7% teeth on the blade. The kinematics of the lateral reamer bit was analysed, the mapping models from the actuation to the reaming radius and speed were established. Concrete samples were reamed indoors from 240mm to 407mm in diameter, the reaming cutting load and time length were measured and analysed. The lateral reamer bit was approved with the experiment results, this study provided equipment support for digging the planting hole in rocky abandoned mine areas and also expanded the PDC bit application.

A Framework for Ranking the Environmental Risk of Abandoned Mines in the State of Minas Gerais/Brazil

Abandoned mines are a major mining liability for the state of Minas Gerais, Brazil. The impacts and risks of abandoned mines are specific to the location and type of ore, but they cover social, economic, and cultural aspects. A central element of an abandoned mine management policy is the definition of a methodology to identify and rank characteristics of abandoned mines that pose a risk to the environment and society. This article presents a methodology for the ranking of environmental risks for abandoned mines in the state of Minas Gerais based on different evaluation factors of their external effects on the environment, safety, the population and surrounding areas, heritage and the landscape. The environmental risk of the abandoned mine area was generated to establish the “Abandoned Mine Area Environmental Risk Hierarchy”. To achieve this a multi-criteria analysis (using the Analytical Hierarchy Process (AHP)) was adopted with each preponderant factor being compared and measured. The results show that the use this framework can support in the decision-making process of an environmental agency for developing the intervention aimed at situations of greater gravity, which, ultimately, may require the use of public resources to reduce risks.

Landslide Susceptibility Zoning Using C5.0 Decision Tree, Random Forest, Support Vector Machine and Comparison of Their Performance in a Coal Mine Area

The main purpose of this study is to establish an effective landslide susceptibility zoning model and test whether underground mined areas and ground collapse in coal mine areas seriously affect the occurrence of landslides. Taking the Fenxi Coal Mine Area of Shanxi Province in China as the research area, landslide data has been investigated by the Shanxi Geological Environment Monitoring Center; adopting the 5-fold cross-validation method, and through Geostatistics analysis means the datasets of all non-landslides and landslides were divided into 80:20 proportions randomly for training and validating models. A set of 15 condition factors including terrain, geological, hydrological, land cover, and human engineering activity factors (distance to road, distance to mined area, ground collapse density) were selected as the evaluation indices to construct the susceptibility assessment model. Three machine learning algorithms for landslide susceptibility prediction (LSP) including C5.0 Decision Tree (C5.0), Random Forest (RF), and Support Vector Machine (SVM) have been selected and compared through the Areas under the Receiver Operating Characteristics (ROC) Curves (AUC), and several statistical estimates. The study revealed that for these three models the value range of prediction accuracies vary from 83.49 to 99.29% (in the training stage), and 62.26–73.58% (in the validation stage). In the two stages, AUCs are between 0.92 to 0.99 and 0.71 to 0.80 respectively. Using Jenks Natural Breaks algorithm, three LSPs levels are established as very low, low, medium, high, and very high probability of landslide by dividing the indices of the LSP. Compared with RF and SVM, C5.0 is considered better in five categories according to quantities and distribution of the landslides and their area percentage for different LSP zones. Four factors such as distance to road, lithology, profile curvature, and ground collapse density are the most suitable condition factors for LSP. The distance to mine area factor has a medium contribution and plays an obvious role in the occurrence of landslides in all the models. The result reveals that C5.0 possesses better prediction efficiency than RF and SVM, and underground mined area and ground collapse sifnigicantly affect significantly the occurrence of landslides in the Fenxi Coal Mine Area.

INITIAL EVALUATIONS OF NATURAL ( 226Ra, 232Th and 40K) AND ARTIFICIAL ( 137Cs) RADIOACTIVITY OF ESKIKÖY MINERALIZATION AREA (GÜMÜŞHANE, TÜRKIYE)

Within the scope of this study, the natural (226Ra, 232Th and 40K) and artificial (137Cs) radioactivity concentrations of the Eskiköy Mine area within the borders of Gümüşhane, which is located in an important metallogenic belt of Turkey, were investigated. In order to determine the natural and artificial radioactivity of the field soils developed due to mineralization, hydrothermal alteration and weathering, 12 soil samples were taken and activity concentrations of 232Th, 226Ra, 40K and 137Cs radio isotopes were measured with a gamma detector. It was observed that the 40K natural radio isotope activities of the area mostly exceeded the weighted world average, and the 232Th, and 226Ra natural radio isotope activities exceeded the weighted world averages at 5 of the 12 sampling points. It was determined that the artificial 137Cs activity concentrations in the area were above the detection limit at 9 sampling points and above 3 Bq/kg at 8 sampling points. It has been evaluated that the high 137Cs activities detected in the Eskiköy mine area are due to the Chernobyl nuclear power plant accident and similar anthropogenic effects. The mine area was also evaluated in terms of radiation risk in the context of medical geology, with parameters of radiological hazard indices, radium conjugate activity value, absorbed dose rate and annual effective dose rate, and remarkable findings were obtained. When all these findings of the study area are evaluated together, it has been concluded that the Eskiköy mining area should be studied in more detail in terms of natural and artificial radioisotope activity concentrations and their effects on human health.

Ordovician Biostratigraphy of North-West Nelson

<p>Eleven graptolite zones are recognized in New Zealand and are considered to represent most of the Ordovician Period. The most complete fossiliferous section, at Aorangi Mine in Northwest Nelson, is described in detail. New fossiliferous Ordovician sections at Wangapeka Valley and Hailes Knob, in Northwest Nelson, are described and the previously Known sections at Cobb Valley (Northwest Nelson) and the Cape Providence - Preservation Inlet region (Southwest Otago) are discussed The New Zealand zones are correlated with those of Victoria, Australia, and the Victorian stage nomenclature is adopted for New Zealand. In upward sequence the stages and zones are: Lancefieldian (zones 1, Adelograptus, and 2, T.approximatus), Bendigonian (zone 3, T.fruticosus), Chewtonian (zone 4, D.protobifidus), Castlemainian (zones 5, I.c.lunata, and 6, I.c.maximodivergens), Yapeenian (zone 7,Oncograptus), Darriwilian (zones 8, P.etheridgei, and 9, D.decoratus), Gisbornian (zone 10, N.gracilis), Eastonian (zone 11, Orthograptus - lower part) and Bolindian (zone 11, Orthograptus - upper part?). Fossils of lowermost Lancefieldian and uppermost Bolindian age are not yet known in New Zealand. Diagnostic Silurian fossils are also unknown and the next youngest New Zealand fossils are Lower Devonian (Gedinnian?). Previous Work in the Aorangi Mine area is outlined, the geology illustrated by a map, and the stratigraphic column shown to include both older, and younger beds than were previously known. About 8500ft thick, the column comprises, in upward sequence, Webb Formation, Aorangi Mine Formation (with four informal members), Formation A (new and informal, with three members), and Formation B (new and informal). Graptolites are confined to the three younger formations and represent zones 1 to 10, ranging in age from Lancefieldian to Gisbornian. The structure is outlined and illustrated by cross-sections. In Wangapeka Valley, argillites of the Wangapeka Formation contain zone 11 graptolites of Eastonian and lower Bolindian age, and are overlain by 1500ft of quartzite of the Ellis Formation, which has yielded no diagnostic fossils but which is inferred to represent at least part of the Silurian Period. Lower Devonian brachiopods, bivalves, corals and trilobites are known from the uppermost beds of the Ellis Formation, about 1550ft above its base. At Hailes knob, Mount Arthur Marble with fossils of uppermost Ordovician age is overlain by Hailes Knob Quartzite of probable Silurian age. From the Aorangi Mine and Wangapeka areas, one hundred and thirteen graptolite species and subspecies, representing 35 geners, are described. They include one named new species and 49 new records for New Zealand. Stratigraphic and geographic distribution elsewhere in the world is noted. The geners Isograptus Moberg and Paraglossograptus Mu are reviewed, and their New Zealand members described and discussed in detail. The important zonal species and subspecies are also described in detail; the remainder are briefly discussed. One hundred and six taxa are figured. Fossil localities in the areas described are listed with their fossils in appendix I, and details of measured sections are given in appendix II. A summary of Lower Paleozoic fossil localities of Northwest Nelson is given in a supporting paper.</p>

Ordovician Biostratigraphy of North-West Nelson

<p>Eleven graptolite zones are recognized in New Zealand and are considered to represent most of the Ordovician Period. The most complete fossiliferous section, at Aorangi Mine in Northwest Nelson, is described in detail. New fossiliferous Ordovician sections at Wangapeka Valley and Hailes Knob, in Northwest Nelson, are described and the previously Known sections at Cobb Valley (Northwest Nelson) and the Cape Providence - Preservation Inlet region (Southwest Otago) are discussed The New Zealand zones are correlated with those of Victoria, Australia, and the Victorian stage nomenclature is adopted for New Zealand. In upward sequence the stages and zones are: Lancefieldian (zones 1, Adelograptus, and 2, T.approximatus), Bendigonian (zone 3, T.fruticosus), Chewtonian (zone 4, D.protobifidus), Castlemainian (zones 5, I.c.lunata, and 6, I.c.maximodivergens), Yapeenian (zone 7,Oncograptus), Darriwilian (zones 8, P.etheridgei, and 9, D.decoratus), Gisbornian (zone 10, N.gracilis), Eastonian (zone 11, Orthograptus - lower part) and Bolindian (zone 11, Orthograptus - upper part?). Fossils of lowermost Lancefieldian and uppermost Bolindian age are not yet known in New Zealand. Diagnostic Silurian fossils are also unknown and the next youngest New Zealand fossils are Lower Devonian (Gedinnian?). Previous Work in the Aorangi Mine area is outlined, the geology illustrated by a map, and the stratigraphic column shown to include both older, and younger beds than were previously known. About 8500ft thick, the column comprises, in upward sequence, Webb Formation, Aorangi Mine Formation (with four informal members), Formation A (new and informal, with three members), and Formation B (new and informal). Graptolites are confined to the three younger formations and represent zones 1 to 10, ranging in age from Lancefieldian to Gisbornian. The structure is outlined and illustrated by cross-sections. In Wangapeka Valley, argillites of the Wangapeka Formation contain zone 11 graptolites of Eastonian and lower Bolindian age, and are overlain by 1500ft of quartzite of the Ellis Formation, which has yielded no diagnostic fossils but which is inferred to represent at least part of the Silurian Period. Lower Devonian brachiopods, bivalves, corals and trilobites are known from the uppermost beds of the Ellis Formation, about 1550ft above its base. At Hailes knob, Mount Arthur Marble with fossils of uppermost Ordovician age is overlain by Hailes Knob Quartzite of probable Silurian age. From the Aorangi Mine and Wangapeka areas, one hundred and thirteen graptolite species and subspecies, representing 35 geners, are described. They include one named new species and 49 new records for New Zealand. Stratigraphic and geographic distribution elsewhere in the world is noted. The geners Isograptus Moberg and Paraglossograptus Mu are reviewed, and their New Zealand members described and discussed in detail. The important zonal species and subspecies are also described in detail; the remainder are briefly discussed. One hundred and six taxa are figured. Fossil localities in the areas described are listed with their fossils in appendix I, and details of measured sections are given in appendix II. A summary of Lower Paleozoic fossil localities of Northwest Nelson is given in a supporting paper.</p>