scholarly journals The first true millipede—1306 legs long

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Paul E. Marek ◽  
Bruno A. Buzatto ◽  
William A. Shear ◽  
Jackson C. Means ◽  
Dennis G. Black ◽  
...  

AbstractThe name “millipede” translates to a thousand feet (from mille “thousand” and pes “foot”). However, no millipede has ever been described with more than 750 legs. We discovered a new record-setting species of millipede with 1,306 legs, Eumillipes persephone, from Western Australia. This diminutive animal (0.95 mm wide, 95.7 mm long) has 330 segments, a cone-shaped head with enormous antennae, and a beak for feeding. A distant relative of the previous record holder, Illacme plenipes from California, it belongs to a different order, the Polyzoniida. Discovered 60 m below ground in a drill hole created for mineral exploration, E. persephone possesses troglomorphic features; it lacks eyes and pigmentation, and it has a greatly elongated body—features that stand in stark contrast to its closest surface-dwelling relatives in Australia and all other members of its order. Using phylogenomics, we found that super-elongation (> 180 segments) evolved repeatedly in the millipede class Diplopoda. The striking morphological similarity between E. persephone and I. plenipes is a result of convergent evolution, probably for locomotion in similar soil habitats. Discovered in the resource-rich Goldfields-Esperance region and threatened by encroaching surface mining, documentation of this species and conservation of its habitat are of critical importance.

2022 ◽  
Vol 41 (1) ◽  
pp. 54-61
Author(s):  
Moyagabo K. Rapetsoa ◽  
Musa S. D. Manzi ◽  
Mpofana Sihoyiya ◽  
Michael Westgate ◽  
Phumlani Kubeka ◽  
...  

We demonstrate the application of seismic methods using in-mine infrastructure such as exploration tunnels to image platinum deposits and geologic structures using different acquisition configurations. In 2020, seismic experiments were conducted underground at the Maseve platinum mine in the Bushveld Complex of South Africa. These seismic experiments were part of the Advanced Orebody Knowledge project titled “Developing technologies that will be used to obtain information ahead of the mine face.” In these experiments, we recorded active and passive seismic data using surface nodal arrays and an in-mine seismic land streamer. We focus on analyzing only the in-mine active seismic portion of the survey. The tunnel seismic survey consisted of seven 2D profiles in exploration tunnels, located approximately 550 m below ground surface and a few meters above known platinum deposits. A careful data-processing approach was adopted to enhance high-quality reflections and suppress infrastructure-generated noise. Despite challenges presented by the in-mine noisy environment, we successfully imaged the platinum deposits with the aid of borehole data and geologic models. The results open opportunities to adapt surface-based geophysical instruments to address challenging in-mine environments for mineral exploration.


2021 ◽  
Vol 14 (11) ◽  
pp. 6711-6740
Author(s):  
Ranee Joshi ◽  
Kavitha Madaiah ◽  
Mark Jessell ◽  
Mark Lindsay ◽  
Guillaume Pirot

Abstract. A huge amount of legacy drilling data is available in geological survey but cannot be used directly as they are compiled and recorded in an unstructured textual form and using different formats depending on the database structure, company, logging geologist, investigation method, investigated materials and/or drilling campaign. They are subjective and plagued by uncertainty as they are likely to have been conducted by tens to hundreds of geologists, all of whom would have their own personal biases. dh2loop (https://github.com/Loop3D/dh2loop, last access: 30 September 2021​​​​​​​) is an open-source Python library for extracting and standardizing geologic drill hole data and exporting them into readily importable interval tables (collar, survey, lithology). In this contribution, we extract, process and classify lithological logs from the Geological Survey of Western Australia (GSWA) Mineral Exploration Reports (WAMEX) database in the Yalgoo–Singleton greenstone belt (YSGB) region. The contribution also addresses the subjective nature and variability of the nomenclature of lithological descriptions within and across different drilling campaigns by using thesauri and fuzzy string matching. For this study case, 86 % of the extracted lithology data is successfully matched to lithologies in the thesauri. Since this process can be tedious, we attempted to test the string matching with the comments, which resulted in a matching rate of 16 % (7870 successfully matched records out of 47 823 records). The standardized lithological data are then classified into multi-level groupings that can be used to systematically upscale and downscale drill hole data inputs for multiscale 3D geological modelling. dh2loop formats legacy data bridging the gap between utilization and maximization of legacy drill hole data and drill hole analysis functionalities available in existing Python libraries (lasio, welly, striplog).


Land ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 209
Author(s):  
Frederick Gyasi Damptey ◽  
Klaus Birkhofer ◽  
Paul Kofi Nsiah ◽  
Enrique G. de la Riva

The ongoing global deforestation resulting from anthropogenic activities such as unsustainable agriculture and surface mining threatens biodiversity and decreases both soil carbon and above-ground biomass stocks. In this study, we assessed soil properties and below- and above-ground biomass attributes in a restored former gravel mine area in Ghana two decades after active restoration with potted plants and fresh topsoil. We compared conditions to four alternative land-use types (unrestored abandoned gravel mine, arable land, semi-natural forest, and natural forest) representing pre- and post-disturbance as well as natural reference states. We hypothesized that soil properties and related levels of below- and above-ground biomass in the restored area share similarities with the natural reference systems and thereby are indicative of a trajectory towards successful restoration. Eight replicated subareas in each land-use type were assessed for a set of soil parameters as well as below- and above-ground biomass attributes. The soil properties characteristic for the restored area differed significantly from pre-restoration stages, such as the abandoned gravel site, but did not differ significantly from properties in the natural forest (except for bulk density and base saturation). Above-ground biomass was lower in the restored area in comparison to the reference natural forests, while differences were not significant for below-ground biomass. Silt and effective cation exchange capacity were closely related to above-ground biomass, while below-ground biomass was related to soil organic carbon, bulk density, and potassium concentration in soils. Our results suggest that major steps towards successful restoration can be accomplished within a relatively short period, without the wholesale application of topsoil. Improving soil conditions is a vital tool for the successful development of extensive vegetation cover after surface mining, which also affects carbon sequestration by both above- and below-ground biomass. We emphasize that the use of reference systems provides critical information for the monitoring of ecosystem development towards an expected future state of the restored area.


Minerals ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 532
Author(s):  
Georgios Louloudis ◽  
Christos Roumpos ◽  
Konstantinos Theofilogiannakos ◽  
Nikolaos Stathopoulos

Spatial modeling and evaluation is a critical step for planning the exploitation of mineral deposits. In this work, a methodology for the investigation of a multi-seam coal deposit spatial variability is proposed. The study area includes the Klidi (Florina, Greece) multi-seam lignite deposit which is suitable for surface mining. The analysis is based on the original data of 76 exploratory drill-holes in an area of 10 km2, in conjunction with the geological and geomorphological data of the deposit. The analytical methods include drill-hole data analysis and evaluation based on an appropriate algorithm, principal component analysis and geographic information techniques. The results proved to be very satisfactory for the explanation of the maximum variance of the initial data values as well as the identification of the deposit structure and the optimum planning of mine development. The proposed analysis can be also helpful for minimizing cost and optimizing efficiency of surface mining operations. Furthermore, the provided methods could be applied in other areas of geosciences, indicating the theoretical value as well as the important practical implications of the analysis.


1995 ◽  
Vol 32 (2) ◽  
pp. 167-176 ◽  
Author(s):  
Pierre Verpaelst ◽  
A. Shirley Péloquin ◽  
Erick Adam ◽  
Arthur E. Barnes ◽  
John N. Ludden ◽  
...  

The Abitibi–Grenville Lithoprobe project completed a regional (line 21) and a high-resolution (line 21-1) seismic survey in the Noranda Central Volcanic Complex of the Blake River Group, Abitibi, Quebec. Line 21 provides a regional framework in which the Archean crust is divided into three layers, two of which are discussed here: the uppermost layer, which corresponds to the Blake River Group, is the least reflective, and lies above 4 s (12 km), and the mid-crustal layer, which is composed of a complex pattern of generally east-northeast-dipping reflectors and lies between 4 and 8 s. Within the regional data, the Mine Series of the Central Volcanic Complex is imaged as a semitransparent series of reflectors overlying a highly reflective east-facing structure interpreted as the subvolcanic Flavrian pluton. The high-resolution data (line 21-1) were collected in the vicinity of the Ansil mine. The seismic images in this region can be controlled by surface geology and extensive drill-hole data, and the project was designed to test the applicability of seismic reflection profiling in providing structural and stratigraphic information for use in mineral exploration: shallow-dipping reflectors correlate well with lithological variations or contacts in the volcanic sequence; strong subhorizontal reflectors correspond to diorite and gabbro dykes and sills; several abrupt lateral changes in the reflectivity coincide with known intrusive contacts such as the Lac Dufault pluton.


Geophysics ◽  
1984 ◽  
Vol 49 (7) ◽  
pp. 957-980 ◽  
Author(s):  
Alfred V. Dyck ◽  
Gordon F. West

Drill‐hole geophysical surveys are a means of extending the search for massive‐sulfide deposits to depths which are inaccessible to conventional surface techniques. The present investigation combines field and model studies of an electromagnetic (EM) prospecting method which utilizes a large, fixed transmitter loop with a downhole, axial‐component magnetic field sensor (solenoid). The system is shown to be well‐suited for detection of deeply buried massive‐sulfide conductors located in resistive host rock at appreciable distances from the drill hole. We propose that drill‐hole survey data collected with a wide‐band large‐loop EM system can be routinely used for estimating target parameters by forward modeling with two simple conductor shapes: a plate and a sphere in free space. Analysis of confined conductors is facilitated by “eigencurrent decomposition” of the induced current vortex into a set of noninteracting loops with simple RL‐circuit behavior. Solutions have been implemented in interactive computer programs which are fast, inexpensive, and sufficiently versatile to accommodate configurations and waveforms used in many practical EM systems. Both stationary and dynamic aspects of the induction process are exploited for diagnosis of three‐dimensional targets. Field studies at test sites in Sudbury and Noranda base‐metal mining areas with a commercial pulse EM system indicate that many important effects predicted by the model studies are, indeed, observable in survey data.


Minerals ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 847
Author(s):  
Umit Emrah Kaplan ◽  
Erkan Topal

Accurate prediction of mineral grades is a fundamental step in mineral exploration and resource estimation, which plays a significant role in the economic evaluation of mining projects. Currently available methods are based either on geometrical approaches or geostatistical techniques that often considers the grade as a regionalised variable. In this paper, we propose a grade estimation technique that combines multilayer feed-forward neural network (NN) and k-nearest neighbour (kNN) models to estimate the grade distribution within a mineral deposit. The models were created by using the available geological information (lithology and alteration) as well as sample locations (easting, northing, and altitude) obtained from the drill hole data. The proposed approach explicitly maintains pattern recognition over the geological features and the chemical composition (mineral grade) of the data. Prior to the estimation of grades, rock types and alterations were predicted at unsampled locations using the kNN algorithm. The presented case study demonstrates that the proposed approach can predict the grades on a test dataset with a mean absolute error (MAE) of 0.507 and R2=0.528, whereas the traditional model, which only uses the coordinates of sample points as an input, yielded an MAE value of 0.862 and R2=0.112. The proposed approach is promising and could be an alternative way to estimates grades in a similar modelling tasks.


Check List ◽  
2021 ◽  
Vol 17 (6) ◽  
pp. 1745-1749
Author(s):  
Ricardo Palacios Aguilar ◽  
Samuel A. Santa Cruz Padilla ◽  
Víctor H. Jiménez Arcos

We record the third known specimen of Tantilla coronadoi Hartweg, 1944 from Guerrero, Mexico. Our new record extends this species’ distribution by 90 km and to a new Mexican biogeographic province (Balsas Basin). The morphological similarity between this and the two previously known specimens supports the validity of the taxon, and otherwise points to the possible presence of an undescribed taxon on the coast of Guerrero. Additional fieldwork yielding a larger series of this and other infrequently encountered species may enable a better understanding of their distribution, natural history, ecology, and conservation.


2019 ◽  
Vol 219 (3) ◽  
pp. 1474-1490 ◽  
Author(s):  
Gerhard Visser ◽  
Jelena Markov

SUMMARY Thickness of cover over crystalline basement is an important consideration for mineral exploration in covered regions. It can be estimated from a variety of geophysical data types using a variety of inference methods. A robust method for combining such estimates to map the cover–basement interface over a region of interest is needed. Due to the large uncertainties involved, these need to be probabilistic maps. Predominantly, interpolation methods are used for this purpose, but these are built on simplifying assumptions about the inputs which are often inappropriate. The Bayesian estimate fusion is an alternative capable of addressing that issue by enabling more extensive use of domain knowledge about all inputs. This study is intended as a first step towards making the Bayesian estimate fusion a practical tool for cover thickness uncertainty mapping. The main contribution is to identify the types of data assumptions that are important for this problem, to demonstrate their importance using synthetic tests and to design a method that enables their use without introducing excessive tedium. We argue that interpolation methods like kriging often cannot achieve this goal and demonstrate that Markov chain Monte Carlo sampling can. This paper focuses on the development of statistical methodology and presents synthetic data tests designed to reflect realistic exploration scenarios on an abstract level. Intended application is for the early stages of exploration where some geophysical data are available while drill hole coverage is poor.


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