Mortar to Repair Rammed-Earth Walls’ Surfaces: Do we still Need it?

A rammed-earth technique has been echoed worldwide due to being conceived not only as an environment-friendly method of construction but also standing as an alternative method to arguably replacing cement. The technique however shows several pitfalls. One concerns the lengthy process of curing upon erecting the rammed-earth walls due to the low process of a chemical reaction occurred throughout the curing stage. A second bias followed from the slow curing and concerns the degradation accentuated at the outer wall’s texture, particularly at the edges, due to effects of the weather cycle. These drawbacks have been observed while accomplishing a funded research project. This article has at its stake remedying the above pitfalls. A natural sandy limestone shows a low percentage of calcium carbonate needed for a cohesive mixture. The method suggested here is based on an experiment that uses minerals of the fruits’ and vegetables’ waste as a binding substance. Curing time in this method has been reduced to the half. It is also suggested here that each stage has its importance, including mixing the soil particles dry and wet, compacting the moistened soil mixture, a well-made formwork and curing, towards remedying the above pitfalls.

Rock analysis to characterize Saudi soft sandstone rock

As more engineering projects and activities are taking place on and around weak rocks, it is becoming more important to study and characterize them. Since regular practices of rock mechanical testing are not effective for weak rocks, special laboratory tests and measurements were performed to characterize the Alkharj Saudi weak sandstone rock which is a clastic rock dominantly sandy limestone and sandstone. Test results are presented in this paper. Porosity, permeability, and mechanical properties (stress, strain, Poisson's ratio, confined compressive strength and unconfined compressive strength) were obtained and then used to characterize the proposed weak rock. This paper provides a mean of classifying weak soft rocks despite encountered problems in handling and testing such materials.

Upper Cretaceous Stratigraphy and Volcanism in the İğneada region, Pontides, NW Turkey

<p>The Pontide Upper Cretaceous magmatic arc can be traced for over 1000 km along the southern Black Sea coast from Georgia to Bulgaria.  The arc extrusive sequence is well-exposed in the İğneada region in Thrace close to the Bulgarian border. The Upper Cretaceous sequence in İğneada region overlies the schists and phyllites of Strandja Massif with an unconformity. It  has a thickness of over 700 meters and consists at the base of Cenomanian shallow marine sandy limestone, which pass up into pelagic limestone, marn and volcanogenic siltstone with Turonian planktonic foraminifera, including <em>Marginotruncana pseudolinneana</em>, <em>Marginotruncana marginata</em>, <em>Whitenella</em> sp., <em>Whitenella praehelvetica</em>, <em>Muricohedbergella</em> sp.  This indicates that the arc volcanism in the region started in the Turonian. The pelagic limestone, marl, and calcareous siltstone series passes up into a volcanic-volcaniclastic sequence of andesitic tuff, lapillistone, agglomerate, andesitic and basaltic-andesitic lava flows. The volcaniclastic rocks are intercalated with lava flows and with rare pelagic limestone and shale beds. Although it is disrupted by several faults, the volcanic sequence can be traced from older to younger along the coast of İğneada. The sequence starts with andesitic volcaniclastic rocks and lava flows, and changes to basaltic-andesitic and then, again to andesitic rocks. The ocean floor alteration, which is found in all volcaniclastic and volcanic rock samples, and the intercalated pelagic limestones show that the rocks were deposited in deep submarine conditions in an intra-arc to fore-arc environment. Campanian (80.6 ±1.5 Ma) U-Pb zircon ages, which are obtained from the andesitic tuffs at the base of the volcanic-volcaniclastic sequence, indicate a continued magmatism from Turonian to Campanian.</p>

Provenance of Medieval atlantes in the Ribe Cathedral, Denmark, based on geological and palaeontological investigations

An atlante is a corbel figure (or pillar support) sculpted in the form of a man carrying a heavy load. A group of well-preserved stone carved atlantes from c. 1250 carrying the vaults of the Ribe Cathedral in western Jylland, Denmark, represents the antique titan Atlas and are up to 150 cm high. Their obviously foreign origin has so far remained uncertain. The figures are made of a relatively soft, sandy limestone. A new nannofossil analysis of small chips of the chalky and sandy limestone narrows the age of the stone down to the late Campanian (Late Cretaceous). Upper Campanian sandy limestones of this type are exposed in the Münster Basin in North Rhine-Westphalia, western Germany. The Campanian Baumberger Sandstein in this region fits well with the atlantes in terms of lithology and age and is the only possible provenance of the stone. Around 1250 the Baumberger Sandstein was used for baptismal fonts as far north as Ostfriesland at the Dutch-German border, and it is a novel finding of this investigation that it even reached Denmark. The stone was most likely floated along the rivers Lippe and Rhine and shipped via the Wadden Sea to Ribe. It is a remarkably long transport distance for historic commercial stone transportation in continental northern European art in the High Middle Ages.

Pendugaan Potensi Volume Akuifer Menggunakan Metode Geolistrik di Pulau Gili Ketapang, Probolinggo, Jawa Timur

ABSTRAKPengukuran geolistrik dengan menggunakan konfigurasi schlumberger telah dilakukan di Pulau Gili Ketapang, sebuah pulau kecil yang memiliki kepadatan penduduk mencapai 12.356 jiwa/km2. Pengukuran dilakukan di 8 lokasi menggunakan metode pada 8 titik Vertical Electrical Sounding (VES). Hasil pengolahan data geolistrik menunjukkan nilai tahanan jenis akuifer berkisar antara 2,71–206 Ωm pada litologi batugamping pasiran. Potensi volume akuifer terbesar berdasarkan model 2D akuifer air tanah berada di lokasi K-03 dan K-17. Model 3D akuifer air tanah menunjukkan bahwa volume akuifer sebesar 27.689.400 m3 atau sekitar 27.689.400.000 liter. Air tanah di dalam akuifer dapat bertahan selama 68 tahun jika tidak terjadi kenaikan populasi. Selain itu, air tanah juga akan bertahan meskipun tidak terjadi penambahan air di dalam akuifer, baik secara alami ataupun buatan.ABSTRACTGeoelectric measurement using Schlumberger configuration was carried out in Gili Ketapang Island, a small island with a population density of 12,356 people/km2. The measurement conducted at 8 locations using a vertical electrical sounding (VES) method. The result of geoelectric data processing shows aquifer resistivity value ranging from 2.71–206 Ωm at the sandy limestone lithology. The largest aquifer volume potency based on the 2D groundwater aquifer model is in the K-03 and K-17 location. The 3D groundwater aquifer model shows that the aquifer volume is 27,689,400 m3 or about 27.689.400.000 liters. The groundwater inside the aquifer will last within 68 years in a condition where there is no population increase. Besides, the groundwater also lasts even there is no water addition inside the aquifer, by natural or artificial

Exceptional Tl-bearing manganese oxides from Zalas, Krakow area, southern Poland

In the Permian rhyodacite quarry at Zalas near Krakow, southern Poland, thallium-bearing Mn oxides occur in a small fault zone cutting Middle Jurassic sandy limestone poorly encrusted by an oxidized polymetallic mineralization. The encrustation comprises sulphides (pyrite, chalcopyrite, chalcocite, covellite, galena, marcasite), native bismuth, hematite, goethite, cuprite, mottramite, iodargyrite, unrecognized Cu sulphates and Bi oxychlorides as supergene minerals, barite and rare tiny grains of gold. It is most likely connected with rejuvenation of Early-Paleozoic faults during the Alpine orogeny on the Oligocene–Miocene boundary. Rare Tlbearing Mn oxides occur in an outside zone of the encrustations, filling small fractures and voids in limestone forming the fault breccia. Tl contents, reaching 20.82wt% as Tl2O, exceed by more than two orders of magnitude those reported in similar minerals before, making the oxides unique on a world scale. The Tl-bearing Mn oxides from Zalas reflect intensive weathering of an older Tl-bearing sulphide mineralization in an arid climate, involving saline fluids delivered to the groundwater system as the nappe structure of the Carpathians was developing during the Sava tectonic phase Oligocene/Miocene boundary.