Quarry Sites Research Articles

Assessment of Radiation Hazard Indices Caused by Naturally Occurring Radionuclides in Granite Samples from Selected Quarry Site in Kano State, Northwest Nigeria

Assessment of Radiation Hazard Indices Caused by Naturally Occurring Radionuclides in Granite Samples from Selected Quarry Site in Kano State, Northwest Nigeria

Environmental and Social Effects of Stone Quarrying in Bangladesh: A Study in the Khasi People Area in Sylhet

This study investigates how the unregulated and unscientific manner of stone quarrying in Bangladesh degrades the environment and affects the life and livelihoods of the local people. The recent countrywide construction boom and infrastructural development kept the GDP growth constant in Bangladesh. This construction boom generates colossal demand for stones, and the Sylhet region is its major supplier. Although there are laws and legal mechanisms to regulate stone quarrying in the country, the miners do not follow these. This study found that the local Khasi people of the stone quarrying area have been experiencing systematic and forcible dispossession due to merging their lands into stone quarrying sites. These people are the victims of different forms of pollution due to unregulated stone quarrying. And the area has been experiencing a social transformation because of the settling of the people of the mainstream Bengali community from the poverty porn areas of the country to sustain their life by managing their livelihoods by working in the stone quarries. The study also explores how the lack of monitoring and corruption of the state and non-state actors in the stone quarrying sectors degraded the environment and transformed society in the last decades.

A method for full three-dimensional kinematic analysis of steep rock walls based on high-resolution point cloud data

The predisposition of a slope to generate rockfalls is related to the intensity of rock mass jointing and the geometric arrangement of discontinuities intersecting the rock face. With the increasing use of terrestrial laser scanner (TLS) in rock slope surveying, methods have been proposed to semi-automatically extract the spatial properties of outcropping discontinuities from high-resolution topographic data. The present paper builds upon one of such methods (named DiAna), and extends it to enhance the assessment of rockfall susceptibility over steep rock walls. In particular, a Matlab routine (named DiAna-K) that incorporates a full three-dimensional derivation of kinematic analysis principles is introduced. Kinematic tests for plane, wedge, block toppling, flexural toppling, and free fall failure are formulated by explicitly accounting for the presence of overhanging areas of the rock face as well as varying frictional strengths across different discontinuity sets, planes, or intersections between planes. Results from a test application at an abandoned quarry site highlight the ability of the proposed procedure to provide detailed insights into the kinematic feasibility of structurally controlled instabilities. They also demonstrate the importance of properly defining failure mechanisms over steep (and usually undersampled) topographies in order to derive realistic quantifications of rockfall hazards.

Electrical Imaging Characterization of a Dumpsite on an Abandoned Quarry Site in Abeokuta, South West, Nigeria

A resistivity imaging technique was employed to delineate the degree of leachate plume accumulation and migration for possible groundwater pollution in the subsurface of Saje dumpsite on an abandoned quarry site within the Abeokuta metropolis, Ogun State, Nigeria. A total of twenty-five 2D profiles were mapped, adopting Wenner configuration using Ohmega resistivity meter with electrode spacing ranging from 5-25 m and profile lengths of 100 m. The 2D and 3D inversions of the data were carried out by RES2DINV and RES3DINV software, respectively. The inversions revealed both the lateral and vertical extents of conductive zones, mostly in fractured zones that served as the contaminant pathways. The 3D volumetric visualizations of the subsurface were generated by Voxler 4. The 2D and 3D models depicted regions with low resistivity anomalies ranging from 1.33-70.70 and 4.70-13.20 Ωm to maximum penetrated depths of 13.4 and 21.9 m, respectively. This study identified zones of concentrated pollution to depths that could have reached the water aquifer and indicated contaminants migration pathways that could endanger the groundwater as the dumpsite ages.

Extracting new information from old stones: An analysis of three quarries in the semi-arid Pilbara region, northwest Australia

Quarries are important archaeological sites in Australia. They represent the starting point for conditioning variability in stone artefact assemblages (e.g. raw material availability, accessibility, quality, size and shape) and serve as a basis to track human movement from source to discard. Despite this, there is relatively little published research on quarries. For example, in the Pilbara, Western Australia, where stone artefact assemblages are ubiquitous, the paucity of published quarry research makes it difficult to accurately reconstruct patterns of past human behaviour. This research begins to address these issues through the application of a suite of analytical techniques to three quarry sites located in Puutu Kunti Kurrama and Pinikura (PKKP) Country in the inland Pilbara. Some variability in site use and reduction occurs between the three quarries. However, a clear pattern of assemblage formation involving natural heat fracture, non-intensive reduction, core transport, high proportions of non-intensively used tools and non-economic tool selection, was identified at all sites. The results demonstrate clear planning and manipulation of stone resources by Aboriginal people in the raw material rich Hamersley Range and demonstrate the vital importance of quarries as multi-functional locations in understanding wider systems of Aboriginal interaction with the Pilbara landscape.

Water Management Practices and Environmental Attitudes of Riparian Communities in Sapangdaku River, Cebu Island, Philippines

Understanding the social-ecological dynamics of freshwater ecosystem is critical for effective planning and sustainable use of the resource. The study aimed to determine the socio-demographic profile, anthropogenic activities, water utilization of the residents, and waste disposal practices along the Sapangdaku River. Here, we examined water utilization, waste disposal practices and their corresponding impact to health, and environmental attitudes of riverside dwellers (n=120) in Sapangdaku River by using a standardized social health and environmental attitudes survey, respectively. Results show that while river water is still largely used for bathing and backyard farming, its known function as (a) disposal area of human and animal waste, (b) quarry site for pebbles and sand and (c) laundry area significantly decreased in recent years. Responses revealed that occurrence of very common ailments such as cough, gastroenteric problems and skin problems are partly associated to poor river water quality. In terms of people’s environmental attitude, ecocentrism is both positively correlated to environmental movement activism (r=0.445, p=0.000) and human utilization of nature (r=-0.275, p=0.006), putting prime value on the sustainable use of river water that provides benefit to the community. Similarly, environmental movement activism and human utilization of nature (r=-0.327, p=0.001) indicates willingness to participate in environmental activities, hence supported by their decision not to use their environment unfavorably. These findings suggest that community’s concern for the river water resulted to increased participation in various strategies to better maximize the use of the river for various purposes. However, efficient management and restoration of river quality require a holistic view of the problem.

Petrological footprints of the millstones of Megara Hyblaea (Sicily Island, Italy) highlight the human interactions with Mediterranean volcanoes

A petrographic and geochemical study of several volcanic millstones, representative of 119 artifacts found in the ancient Greek colony of Megara Hyblaea (Sicily Island) and recording the grinding device evolution from the Archaic to the Hellenistic period, unravelled the volcanoes involved as quarrying and production areas. This was possible also through the comparison with available petrographic and geochemical literature data of ancient volcanic millstones found in the whole Mediterranean. Saddle querns, hopper-rubber, rotary Morgantina- and Delian-type millstones of Megara Hyblaea consist of lithotypes belonging to five magmatic series: Tholeiitic, Na-Alkaline, Tholeiitic Transitional, Calcalkaline and High-K Alkaline. A provenance from the Eastern Sicily, i.e. mugearites from Etna and basalts and basaltic andesites from the Hyblaean Mountains were recognized for all the four investigated grinding devices. By contrast, a sea-trade is involved for several saddle querns made of calcalkaline basaltic andesites and andesites lavas (Aegean Islands) and two Morgantina-type millstones consisting of a calcalkaline rhyodacite ignimbrite from the quarrying site of Mulargia (Sardinia). A wide millstone trade, both local (Eastern Sicily) or maritime (Central-Eastern Mediterranean) was thus constrained through six centuries, from the foundation of the Greek colony up to the destruction of the settlement at the end of third century BCE. Finally, Vulture Volcano (southern Italian peninsula) is the most probable candidate for the only leucite- and haüyne-bearing phonolite of the High-K Alkaline Series.

Chemical analysis of glass beads in Palau, western Micronesia reveals 19th century inter-island exchange systems in transition

For centuries, glass money beads (udoud) have played a critical role in cultural and economic exchanges in the Palauan archipelago (western Micronesia) since their first appearance ca. AD 600–950 from East Java and mainland Southeast Asia. Later, as part of their stone money (rai) quarrying activities, visiting Yapese islanders negotiated access to quarry sites and purchased provisions using glass beads, corvée labor, and other exchange valuables. Here, we present morphological and chemical composition analysis of 38 glass beads recovered from Chelechol ra Orrak, the only quarry site where udoud have been recovered. Analysis reveals that most of the beads were manufactured in Europe, with many originating in Bohemia (present-day Czech Republic) ca. AD 1830–1850. Many of these beads would have been regarded as cheldoech, a category of udoud that largely went out of circulation in the 1920s due to the ease of counterfeiting. Although this category of udoud could be easily counterfeited and beads from Yap lacked the requisite life histories associated with traditional udoud, Palauans accepted them as authentic. However, our research suggests that cheldoech may have depreciated in value well before the 1920s, with Palauans valuing and exchanging this category of udoud in new ways, including interment with burials.

Reclamation of a limestone quarry: effect of poultry manure and humic acid on the soil improvement

Limestone processing produces dust covering the soil around the quarry site and may affect soil fertility. Post-mining activities in a forest area are mandatory to restore biodiversity, such as tree species of non-wood products. This study aimed to determine the impact of limestone dust on soil and measure the effectiveness of soil treatment for revegetation. This study employed a randomized block design with three soil groups, i.e. uncovered with limestone dust, covered with 2.5 cm limestone dust, and covered with 5 cm limestone dust. Each group had five replications and was treated with poultry manure (0 kg m<sup>-2</sup>, 5 kg m<sup>-2</sup>, 10 kg m<sup>-2</sup>, and 15 kg m<sup>-2</sup>) and 2 L of 1% (v/v) humic acid. The amendment of manure and humic acid increased the soil organic C, total N, C/N ratio, and exchangeable K but increased the soil available P content. The soil respiration and total bacteria increased along with the thinning of the limestone dust. Overall, the treatments significantly affected pH, C/N ratio, exchangeable K, and electrical conductivity. At the same time, the group significantly affected organic C, total N, C/N ratio, exchangeable K, electrical conductivity, cation exchange capacity, bulk density, total bacteria, and clay. Based on land suitability assessment guidelines, the soil required nutrient improvement and pH reduction to grow proper non-wood products tree species.

Syntaxonomy of restoration vegetation in quarries in Central Polissya

Syntaxonomy of restoration vegetation in quarry sites in Central Polissya of Ukraine, including 25 classes, 36 orders, 62 alliances, 116 associations, and two unranked communities, is presented. Based on the frequency of occurrence of vegetation plots, we have identified typical and atypical environments in existing and abandoned quarries. The classes Molinio-Arrhenatheretea, Artemisietea vulgaris, Phragmiti-Magnocaricetea, Plantagenetea majoris, and Epilobietea angustifolii were found to be the most common. Predominance of the grassland stage in vegetation restoration under significant or moderate anthropogenic impact is demonstrated. The environmental factors and features of seed dispersal affect the mode and tempo of vegetation restoration in disturbed habitats of open pit mining. Meadow vegetation is predominant on the plateau around the zone of active production; herbaceous and woody plants penetrate the slopes simultaneously. Steep vertical outcrops of crystalline rocks for a long time remain uninhabited by higher vascular plants. Plants grow exclusively in the crevices of crystal blocks filled with loose rocks, soil, and small organic residues. On the slopes of loose sedimentary rocks, the meadow stage is not gradually transformed into the phanerophyte stage. The rate of vegetation restoration depends on the slope angle. Such successions form large ecotone areas due to numerous unfilled ecological niches in the quarry ecosystems. These areas are most vulnerable to the penetration of invasive plant species.

Detailed Chemical Analysis of Unusually Weathered Rocks

Objectives: This study aimed to conduct a detailed chemical analysis of the Samanalawewa dam to provide information on its weathering conditions. Method: The mineralogical composition of the dam was analyzed by powder Xray diffraction (PXRD), atomic absorption spectroscopy (AAS), gravimetric, and X-ray fluorescence (XRF) analysis in order to identify chemical changes that have taken place. Findings: Widespread discoloured (brick red) and crushable areas in the dam and the quarry site indicate weathering of the compositional rocks. Each weathered rock sample showed a similar compositional pattern to each other as well as charnockite (CHA) rather than the other structural rocks of the dam; biotite gneiss (BIO), garnet biotite sillimanite gneiss (GAR), and limestone (LIM) indicating that only CHA has been weathered rapidly. Since LIM is not affected and the contact water (pH; reservoir 6.79 - 7.12 and holes in the quarry site 6.43-6.78) is almost neutral, this rapid weathering has not been governed by general chemical weathering processes like acid rains or stormwater. The relative contents of aluminium and magnesium have decreased during the weathering process while increasing the relative content of iron as well as sodium, which is a mobile element. The potassium content also has not decreased significantly. Moreover, chemical weathering indices like chemical index of alteration (CIA) and chemical index of weathering (CIW) values for completely weathered rocks were less than 50 revealing their unsuitability to assess the degree of weathering of the Samanalawewa dam. Novelty: Charnockite in the Samanalawewa dam has been weathered rapidly and chemical weathering indices; CIA and CIW are not valid to assess its degree of weathering. Keywords: Metamorphic; Charnockite; Rock weathering; Rock composition; Chemical weathering indices

Characterization of Clay and Granite Dust Blends as Novel Materials for Energy Storage and Diffuser in Constructing Flat-plate Solar Collector

Sun is the main source of solar energy, and the energy it releases to the Earth’s surface in one hour is more than what the whole planet consumes in a year. This present work is about characterizing novel material that can be used as energy storage and diffuser in constructing flat plate solar collector. Materials used are clay and granite dust obtained from Okelele and Kulende Quarry sites, both in Ilorin, Kwara State, Nigeria. The materials were sun-dried; the clay crushed before the two materials were sieved into different particle sizes. They were thereafter blended into different ratios and then characterized for thermal, physical and mechanical properties. Results showed that the highest thermal conductivity, thermal diffusivity and compressive strength were obtained from sample of particle size 0.075 mm and clay: granite ratio 50:50 (0.268176 W/mK, 3.58514 10–4 m2/sec and 3.571 N/m2, respectively). This same blend has a density of 0.91 g/cm3 and specific heat capacity of 824 J/kgK. This sample, having the optimal thermal, physical and mechanical properties will be a good replacement for conventional insulating materials currently being used for solar flat-plate collector construction as it will serve as both energy storage and diffuser.
 Keywords: Solar energy; solar collector; insulating material; clay; granite dust; thermal conductivity; thermal diffusivity

Assessment of the Socio-Economic and Health Impact of Quarrying on the Inhabitants of Kenta Logemo Village in Odeda Local Government Area, Ogun State, Nigeria

Quarry is a small scale industry generating materials used for construction, thus contributing to the Gross Domestic Product (GDP) of the country. This study was carried out to evaluate the socio-economic and health impact of quarry on the inhabitants of Kenta Logemo Village in Odeda Local Government Area, Ogun State. The sampling was carried out in three different distances (100, 200, 300 m) around the quarry site and 1000 m (control). The air quality monitored are (gaseous component) CO2 NO2, CO, volcanic organic compound (VOC) and particulate matters (PM) and noise level. Thirty copies of questionnaire were administered to the workers and inhabitants. The result showed that the gaseous pollutants were more pronounced at 100 m and there were no significant differences (p > 0.05) among the distances and they were below Federal Ministry of Environment (FmEnv) limit. The PM10 at 200 m (137.1 ug/m3 ) was highest among three types of particulate matters and distances monitored. There were no significant differences (p > 0.05) across distances from the quarry. Noise level ranges from 59.3 to 86.3 dB(A) and higher than the control (50. 8 dB(A) but below FmEnv limit (90 dB(A). The analysis of the questionnaire revealed that the vegetation (40.0 %) and animal (46.7 %) were into extinction and threatened and dust (30.0 %) covered food or cash crops. Water bodies were affected by taste, colour and turbidity (63.3 %). Among the diseases suffered were catarrh (53.3 %) and eye irritation (46.7 %). In conclusion, the surrounding of the quarry is not polluted with CO2 NO2, CO, VOC, PM and noise but there is significant effect of the activity of quarry on the health and socio-economic of the inhabitants hence, improved the economic status.

Assessment of Bholari River Sand for its Geotechnical Characterization as Fine Aggregate

Present study is aimed at assessment of Bholari river sand for its geotechnical characterization and suitability as fine aggregate which is being quarried in Jamshoro district, Sindh, Pakistan. For this purpose, sand samples (n=11) were collected from quarry sites and main river channel. Physical properties reveal that Bholari sand is mainly coarse to fine in size (0.2 mm-5 mm). Average values of fineness modulus, specific gravity, bulk density and void content of collected samples are 2.58, 2.56, 1659.90 kg/m3 and 35.12% respectively which varied within the corresponding permissible ranges of ACI (American Concrete Institute). Carbonate content of about 57.59% is also in agreement with corresponding range for fine aggregate. Petrographic examination revealed that Bholari River sand mainly comprises of quartz and rock fragments with subordinate limestone fragments. As per classification of Dott (1964), Bholari sand is lithic arenite where quartz (50%) occurs as main mineral followed by rock fragments (30%), feldspars (15%) and other opaque minerals (5%). Texturally, the sediments are angular (77%) to sub-round (33%). All these physical properties lie within the range set by National Highway Authority (NHA) and American Standard of Testing Material (ASTM). It is concluded that Bholari River sand is suitable for use in concrete mixed with cement and asphalt.

The Strength of Concrete Made from Various Aggregate

Abstract: The cost of river sand is much due to excessive cost of transportation from its natural sources. Also huge amount of depletion of these sources leads to environmental problems. Also environmental transportation and other constraints make the availability and use of river sand less attractive, hence it is very necessary now to find substitutes or replacements for river sand. The result for the sieve analysis carried out showed that the aggregates fell within the upper and lower limits of grading requirement. The specific gravity of river sand used was 2.6, while that of grit was determined and the results obtained from two outcomes were 2.23 and 2.45, and the average found was 2.34. The bulk density of river sand was found to be 1550kg/m3 and that of grit was 1650kg/m3. The slump obtained from specimens with different W/C of 0.35, 0.45 and 0.60 ranged from 51 – 86mm. The concrete produced from 100% grit as fine aggregate with a water-cement ratio of 0.45, produced a maximum compressive strength of 29.56 N/mm3 at the highest curing age in days, while sand alone as fine aggregate in one of the concrete mix, produced the least compressive strength of 17.33 N/mm3. Hence, the use of grit in construction is considered more economical since it offers optimum utilization and it is commonly available at different quarry sites.

High resolution elemental characterization of prehistoric flint sources in southern Israel: Implications for archaeological provenance studies

Identifying the geological sources of archaeological flint is crucial to various studies in prehistoric research. Here we present a study of flint sources in southern Israel using elemental analysis. Six Neolithic quarries and three geological outcrops of several geological formations were sampled and analyzed by ICP-MS in order to investigate whether differences in trace element concentrations can be used to distinguish between flint sources. Using (1) patterns of chondrite-normalized rare earth elements (REE), and (2) new advanced statistical methods utilizing the concentrations of REE and 25 additional elements, we were able to clearly differentiate between Upper Cretaceous and Eocene flints, and in certain cases also between flint sources of different ages within the Upper Cretaceous across the southern Levantine landscape. In addition, we used the newly established elemental database and the methods developed in this research as a pilot study towards establishing a regional dataset and locating target sites for flint exploited in those sources. This concept is evaluated by investigating the elemental analyses of flint artifacts from the Neolithic settlement which is nearest to the quarries and outcrops in the eastern part of our research area – the late Pre-Pottery Neolithic settlement in the Wadi Faynan region (Jordan). The current results indicate that the flint from the studied quarrying sites in the eastern Negev was probably not exploited by the inhabitants of Wadi Faynan during the Neolithic, but suggest that multiple sources were used. This highlights the need to expand the database by analyzing additional flint from other potential sources.

HUMAN HEALTH RISK ASSESSMENT OF HEAVY METALS IN CASSAVA TUBERS FROM QUARRY SITES IN OLD NETIM, AKAMKPA LGA, CROSS RIVER STATE, NIGERIA

This study investigated the human health risk assessment of heavy metals in cassava tubers cultivated within three quarry sites in Old Netim, Akamkpa LGA, Cross River State, Nigeria. Soil and Cassava tubers were obtained from three (3) quarry sites of 4.5km apart and 20km from the Control at Oban Okoroba. Composite of soil samples from 0km, 0km, 0.3km, 0.6km and 0.9km were obtained at a depth of 15cm using soil auger while the cassava samples were obtained using a spade. The concentration of heavy metals was determined by Atomic Absorption Spectrophotometry (AAS). Results showed Lead (Pb), Cadmium (Cd), Copper (Cu), Arsenic (As) and Manganese (Mn) had relative abundance in the order Mn > Cu > Pb > As > Cd across all locations and samples. Maximum levels of Mn and Cu were present in cassava tubers obtained from quarry site C (78.651 ± 10.048 mgkg-1 and 7.138 ± 3.203 mgkg-1), while that of Pb, As, and Cd were present in cassava tubers obtained from quarry site D (2.018 ± 1.251 mgkg-1, 0.195 ± 0.205 mgkg-1, and 0.167 ± 0.116 mgkg-1 respectively). Bioaccumulation Factor (BF) of heavy metals from soil to cassava tubers revealed high accumulation of Mn with BF > 1 in tubers across all quarry sites. Estimated daily intake (EDI), Target Hazard Quotient (THQ), and Life Carcinogenic Risk (LCR) showed consumption of cassava tubers cultivated within quarries in Old Netim is safe and free of non-carcinogenic and carcinogenic hazards. However, THI revealed the possible emergence of a non-carcinogenic threat with continuous consumption of these local tubers.

The Influential Role of Powder Factor vs. Delay in Full-Scale Blasting: A Perspective Through the Fragment Size-Energy Fan

The fragmentation of 12 full-scale one-row blasts has been measured by sieving a large portion of the muckpiles. The procedure followed, the difficulties encountered and the solutions adopted to construct the fragment size distribution curves are described in detail; 11 curves were finally constructed as production constraints prevented the required measurements on one of the blasts. The blasts covered a powder factor range between 0.42 and 0.88 kg/m3, and were initiated with two significantly different delays, 4 and 23 ms between holes, to assess the influence of both powder factor and delay on fragmentation. The size distributions are well represented by the Swebrec function, which strongly suggests that the dependence of fragmentation with the powder factor can be analyzed by the fragmentation-energy fan. The result is excellent, and the frag-energy fan model in its simplest form (a four-parameter function) is able to predict sizes between percentage passings 92 to 8% with a mean error of 14.4% and a determination coefficient R2 as high as 0.976. The powder factor above grade has been used, in its energy form obtained as the product of the mass powder factor by the explosive energy per unit mass. The incorporation of six more fragment size distributions, also obtained by sieving in a previous blasting project in the same rock mass, but with different layouts, explosives, delay and blast direction, only reduces R2 to 0.968 and increases the mean error to 15.3%. A strength dependence with the size of the blasted block (burden, bench height, etc.) has been tested for inclusion in the fan formulation, with minor improvement compared with the powder factor alone, as the variation in size of the blasts was very limited. Some size descriptors as in-situ block size and fracture intensity have also been tested, though variations were also limited as all blasts were carried out in the same quarry site, not improving the prediction errors when other blast dimensions (e.g., burden) are used. Incorporating the effect of delay in the fragmentation-energy fan model has been attempted with a cooperation function modifying the powder factor, increasing from instantaneous to an optimum delay value, then decreasing as the delay further increases. The effect of such a function is noticeable in terms of improved prediction; the data analyzed, however, do not allow for a definitive statement on an optimum delay value as calculations with different fan characteristics and data result in different optimum values. The effect of the delay on the fragment size varies with the percentile, from about 10–15% for the high percentiles to somewhat more than 30% for the lower percentiles.

Kaizer Hill (Modi'in), a pre-pottery neolithic a quarry site - the terraced slopes.

The research of the Kaizer Hill site (the Hilltop and its Terraces), recognized as a Pre Pottery Neolithic A (PPNA) quarry site, involved studies of the rock damage associated with the quarrying activities as well as of the recovered material remains, mostly chipped stone artifacts. We present here the results of our on-site explorations (excavations, surveys and surface-collections), focusing on the findings deriving from the Terraces. Diverse rock damage patterns were identified and described, portraying systematic rock mass-exploitation through quarrying fronts, natural rock joints and fissures enlargement, drilling and chiseling. There are multiple indications that the local bedrock (Bi’na Formation, Turonian) comprising flint and limestone was quarried under a systematic quality evaluation, leaving residual flint unsuitable for exploitation. Of interest to note that nearly all of the flint artifacts excavated and collected on the Terraces were made on raw material transported from the Hilltop (Mishash Formation, Campanian), knapped in-situ, on the quarried rock surfaces of the slopes. The flint tools bear witness to intensive use involving mainly boring and drilling. The dominant tool type is the flint axe for which a variety of waste products related to its production were found in-situ, enabling the reconstruction of axe reduction sequence. Similar axes and waste products were found in many PPN sites indicating that there was a common, widely-used scheme of making flint axes during the PPN. Interestingly, besides the flint waste, there were also limestone waste products typical of the last shaping and thinning stages of axe production, indicating that limestone axes were shaped technologically similar to the flint ones, contrary to what has been assumed before. Rare findings, such as obsidian pieces, originating from much further a-field indicate ties with other PPN communities, near and/or far. Overall, this study provides unique and novel insights on Levantine PPN lifeways.

Preliminary Mineralogical Characterization of Branching Selenite Gypsum: New Insights for the Paleoenvironmental Reconstruction and Mechanical Characterization

The present study proposes a characterization of textural and mineralogical features of branching selenite gypsum lithofacies from the Monferrato area (NW Italy). This facies is considered to have appeared during the sequence of the primary lower gypsum of the Messinian Salinity Crisis starting from the sixth stratigraphical cycle, providing a useful tool for stratigraphic correlation throughout the Mediterranean. It is often associated with thick and continuous beds that are exploited by open-pit and underground quarries. We provide the results of a characterization of the non-gypsum minerals that represent approximately 10% in weight of the rock. Mineralogical data were collected with energy-dispersive X-ray spectroscopy (EDS) and X-ray powder diffraction (XRPD) techniques. In addition, a detailed characterization of clay families was performed through dedicated XRPD analyses. Results highlight the presence of detrital minerals (quartz, feldspars and clay minerals), calcite, dolomite and epsomite. Clay analysis registered the existence of five different families (illite, chlorite, smectite and two mixed layers). These mineralogical data suggest that the origin of this lithofacies is connected to both depositional processes and in situ precipitation processes under different conditions of saturation of the brine (respectively undersaturated and supersaturated in sulfates). The mineralogical and textural heterogeneity also represents an important element in controlling the mechanical response of the material and the consequent stability of quarry sites.