Indian Rocks Research Articles

Advanced machine learning approaches for uniaxial compressive strength prediction of Indian rocks using petrographic properties

Advanced machine learning approaches for uniaxial compressive strength prediction of Indian rocks using petrographic properties

First Report of an Alien Whitefly Predatory Beetle, Delphastus pallidus (LeConte) (Insecta: Coleoptera: Coccinellidae) from South Punjab, Pakistan

Delphastus pallidus (LeConte) is an important predatory beetle reported for effective control of whiteflies including Bemisia tabaci, Aleurotrachelus trachoides, Paraleyrodes bondari and Dialeurodes citrifolii. Many other members of genus Delphastus are well known predators of multiple whitefly species such as Delphastus catalinae (Horn). The members of this genus have predatory potential against all the stages of whitefly including eggs, nymphs and adults. This genus was reported in earlier 1950s from Florida on citrus whitefly. The later studies have reported it from Beach and the Mims areas in 1951, Indian Rocks Lake Alfred areas in 1953. It was not reported against cotton whitefly from anywhere of Pakistan. The Pest Warning Quality Control of Pesticides, Punjab team Multan reported it from cotton fields. Samples were collected and got identified from the Department of Entomology, Muhammad Nawaz Sharif University of Agriculture, Multan. After morphological and taxonomic identification, it was identified as Whitefly Predatory Beetle, Delphastus pallidus (LeConte) (Insecta: Coleoptera: Coccinellidae). Extensive surveys during the 3rd week of August 2022 reported its presence in 15 tehsils of cotton zone, South Punjab, Pakistan.

India (Tethyan Himalaya Series) in Central Myanmar: Implications for the Evolution of the Eastern Himalayan Syntaxis and the Sagaing Transform‐Fault System

AbstractIn the Katha Range of central Myanmar, lithologic tracers and pressure‐temperature‐deformation‐time data identify Cambro‐Ordovician, Indian‐affinity Tethyan Himalaya Series, located ∼700 km from their easternmost outcrop in S‐Tibet, and ∼450 km from Himalayan rocks in the Eastern Himalayan Syntaxis. Metamorphism began at ∼65 Ma, peaked at ∼45 Ma (∼510°C, 0.93 GPa), and exhumation/cooling (∼25°C/Myr) occurred until ∼30 Ma in a subduction‐early collision tectonic setting. When the Burma microplate—part of the intra‐Tethyan Incertus arc—accreted to SE‐Asia, its eastern boundary, the southern continuation of the Indus‐Yarlung suture (IYS), was reactivated as the Sagaing fault (SF), which propagated northward into Indian rocks. In the Katha rocks, this strike‐slip stage is marked by ∼4°C/Myr exhumation/cooling. Restoring the SF system defines a continental collision‐oceanic subduction transition junction, where the IYS bifurcates into the SF at the eastern edge of the Burma microplate and the Jurassic ophiolite‐Jadeite belts that include the Incertus‐arc suture.

Indian rocks may harbor 1.6-billion-year-old ancestors of complex life

Indian rocks may harbor 1.6-billion-year-old ancestors of complex life

Prediction of abrasiveness index of some Indian rocks using soft computing methods

The present paper mainly describes the prediction methodology to determine the Cerchar Abrasiveness Index and Penetration Rate related to rock excavation using simple geomechanical parameters as predictors. As abrasiveness of rocks is influenced by many geomechanical parameters, an attempt is made to use these parameters for its prediction using Multivariate Regression Analysis and Artificial Neural Networking. Abrasiveness Index as well as Penetration Rate are very vital in deciding the economics of the excavations as they directly govern the wear and tear of drill bit. It was observed that ANN shows a better prediction capability than MVRA using UCS, Point load index, P wave velocity and Young’s modulus as predictors.

Modified Mohr–Coulomb criterion for non-linear triaxial and polyaxial strength of jointed rocks

Rocks encountered in civil and mining engineering fields are invariably jointed and act under triaxial or polyaxial stress conditions. The Mohr–Coulomb shear strength criterion is the most widely used criterion for jointed rocks. In its present form there are two major limitations of this criterion; firstly it considers the strength response to be linear, and, secondly the effect of the intermediate principal stress on the strength behaviour is ignored. A modified non-linear form of Mohr–Coulomb strength criterion has been suggested in this study to overcome these limitations. Barton's concept of critical state for rocks has been imbibed in the linear Mohr–Coulomb criterion to deduce a semi-empirical expression for non-linear criterion. However, the shear strength parameters of the conventional Mohr–Coulomb criterion are used in the proposed criterion. The proposed criterion is a simple and rational nonlinear polyaxial strength criterion for anisotropic jointed rocks. In an earlier publication [1] the applicability of the criterion was evaluated for intact rocks. In present paper the criterion is extended to jointed rocks, which are anisotropic in nature. The applicability of the proposed criterion has been verified by applying it to extensive experimental data on triaxial and polyaxial test results on jointed rocks available from literature. Applicability of the criterion, to explain rock burst conditions for some Indian rocks, is also demonstrated.

Where does India end and Eurasia begin?

The Indus Suture Zone is defined as the plate boundary between India and Eurasia. Here we document geochronological data that suggest that Indian rocks outcrop to the north of this suture zone. The inherited age spectrum of zircons from mylonitic gneiss collected in the southern part of the Karakorum Batholith is similar to those obtained from the Himalayan Terrane, the Pamir and is apparently Gondwanan in its affinity. These data are taken to indicate that the Karakorum Terrane was once a component of Gondwana, or at least derived from the erosion of Gondwanan material. Several continental ribbons (including the Karakorum Terrane) were rifted from the northern margin of Gondwana and accreted to Eurasia prior to India-Eurasia collision. Many therefore consider the Karakorum Terrane is the southern margin of Eurasia. However, we do not know if rifting led to the creation of a new microplate(s) or simply attenuated crust between Gondwana and these continental ribbons. Thus there is a problem using inherited and detrital age data to distinguish what is “Indian” and what is “Eurasian” crust. These findings have implications for other detrital/inherited zircon studies where these data are used to draw inferences about the tectonic history of various terranes around the world.

Radon ( 222Rn) level variations on a regional scale from the Singhbhum Shear Zone, India: A comparative evaluation between influence of basement U-activity and porosity

This paper is devoted to the comparative study of the radon flux vs. uranium content and radon flux vs. porosity for mineral samples from some typical Indian rocks (schists, quartzites, argillaceous quartzites, slates and granites) used as building materials, primarily around the Singhbhum Shear Zone, Jharkhand State. As the radon flux of any particular rock type was investigated with reference to its uranium activity and porosity, a good concordance of porosity on radon flux was observed. Such a significant influence of porosity on radon flux was also observed when different rock types were inter-compared. For example, granite that is commonly considered as typical source of indoor radon showed depleted level of radon flux when compared to most other rocks in the study area. In case of rocks such as slates and argillaceous quartzites, low porosity exhibited reduced radon flux in spite of their enhanced radioactive source content. It is concluded that it may not be advisable to utilize materials that are uranium depleted for construction purposes without giving importance to the materials' porosity.

Groundwater arsenic contamination affecting different geologic domains in India—a review: influence of geological setting, fluvial geomorphology and Quaternary stratigraphy

Arsenic contamination in groundwater is pervasive within lowland organic-rich Bengal Delta and narrow entrenched channels in the Middle Ganga floodplains. Local areas of Damodar fan-delta and isolated areas within the Dongargarh Proterozoic rift-zone in central India are also contaminated. In this rift-zone, arsenic is enriched in felsic magmatic rocks and weathered rocks and soils from local areas are enriched further in arsenic and iron. Late Quaternary stratigraphy, geomorphology and sedimentation have influenced groundwater arsenic contamination in alluvium that aggraded during the Holocene sea-level rise. No specific source of arsenic could be identified, although Himalaya is the main provenance for the Ganga floodplain and the Bengal Delta. Gondwana coal seams and other Peninsular Indian rocks might be sources for arsenic in the Damodar fan-delta. As-bearing pyrite or any As-mineral is nearly absent in the aquifer sediments. Arsenic mainly occurs adsorbed on hydrated-iron-oxide (HFO), which coat sediment grains and minerals. Arsenic and iron are released to groundwater by bio-mediated reductive dissolution of HFO with corresponding oxidation of organic matter.

Scour and Burial Mechanics of Objects in the Nearshore

A process-based, numerical, hydrodynamic vortex lattice mine scour/burial model (VORTEX) is presented that simulates scour and burial of objects of arbitrary shape resting on a granular bed in the nearshore. There are two domains in the model formulation: a far-field where burial and exposure occur due to changes in the elevation of the seabed and a near-field involving scour and transport of sediment by the vortices shed from the object. The far-field burial mechanisms are based on changes in the equilibrium bottom profiles in response to seasonal changes in wave climate and accretion/erosion waves spawned by fluxes of sediment into the littoral cell. The near-field domain consists of one grid cell extracted from the far-field that is subdivided into a rectangular lattice of panels having sufficient resolution to define the shape of the object. The vortex field induced by the object is constructed from an assemblage of horseshoe vortices excited by local pressure gradients and shear over the lattice panels. The horseshoe vortices of each lattice panel release a pair of vortex filaments into the neighboring flow. The induced velocity of these trailing vortex filaments causes scour of the neighboring seabed and induces hydrodynamic forces on the object. Scour around the object and its subsequent movement into the scour depression contribute to burial, while far-field changes in local sand level may increase burial depth or expose the object. Scour and burial predictions of mines and mine-like objects were tested in field experiments conducted in the nearshore waters off the Pacific coast of California at Scripps Pier, the Gulf Coast of Florida at Indian Rocks, and off the Atlantic coast of Massachusetts at Martha's Vineyard. Model predictions of mine scour and burial are in reasonable agreement with field measurements and underwater photographs.

Multibeam Observations of Mine Burial Near Clearwater, FL, Including Comparisons to Predictions of Wave-Induced Burial

A Kongsberg Simrad EM 3000 multibeam sonar (Kongsberg Simrad, Kongsberg, Norway) was used to conduct a set of six repeat high-resolution bathymetric surveys west of Indian Rocks Beach (IRB), just to the south of Clearwater, FL, between January and March 2003, to observe in situ scour and burial of instrumented inert mines and mine-like cylinders. Three closely located study sites were chosen: two fine-sand sites, a shallow one located in 13 m of water depth and a deep site located in 14 m of water depth; and a coarse-sand site in 13 m. Results from these surveys indicate that mines deployed in fine sand are nearly buried within two months of deployment (i.e., they sunk 74.5% or more below the ambient seafloor depth). Mines deployed in coarse sand showed a lesser amount of scour, burying until they present roughly the same hydrodynamic roughness as the surrounding rippled bedforms. These data were also used to test the validity of the Virginia Institute of Marine Science (VIMS, Gloucester Point, VA) 2-D burial model. The model worked well in areas of fine sand, sufficiently predicting burial over the course of the experiment. In the area of coarse sand, the model greatly overpredicted the amount of burial. This is believed to be due to the presence of rippled bedforms around the mines, which affect local bottom morphodynamics and are not accounted for in the model, an issue currently being addressed by the modelers. This paper focuses specifically on two instrumented mines: an acoustic mine located in fine sand and an optical instrumented mine located in coarse sand.

An Acoustic-Instrumented Mine for Studying Subsequent Burial

The U.S. Navy is supporting the research to develop and validate stochastic, time-dependent, mine burial prediction models to aid the tactical decision making process. This research requires continuous monitoring of both mine behavior during burial, and the near-field processes responsible for burial. A new instrumented mine has been developed that far exceeds the capabilities of the earlier optically instrumented mine in terms of the burial processes that can be measured. The acoustic-instrumented mine (AIM) utilizes acoustic transducers to measure burial and scour, localized flow rates, and sediment size and concentration in the water column. The AIM also includes sensors for measuring mine orientation and movement, as well as oceanographic information such as significant waveheights, wave period, and water temperature. Four AIMs were constructed and deployed during the Indian Rocks Beach (IRB, FL) and Martha's Vineyard Coastal Observatory (MVCO, Edgartown, MA) mine burial experiments. The results from the field experiments have proven that the sensor suite is viable in providing a wealth of data that are critical in understanding and modeling the complex subsequent burial process.

Measured and Predicted Burial of Cylinders During the Indian Rocks Beach Experiment

Burial of instrumented mine-like cylinders as a result of wave-induced scour was measured during experiments conducted in shallow water (15-16 m) with fine-sand (133-mum) and coarse-sand (566-mum) sediments off Indian rocks beach (IRB), FL. scour pits developed around the instrumented cylinders in the fine-sand site when significant waveheights exceeded 2 m, causing the cylinders to pitch, then roll into the developing scour pits, often changing heading to align parallel with the wave crest. Final cylinder burial was nearly 40 cm (about 70%-80% mine diameter) relative to the sediment-water interface, but only 20%-50% relative to surface area covered. The difference was caused by the lack of complete infilling of scour pits. Little development of scour pits and burial was noted on the coarse-sand site and the cylinders buried to only 20%-40% of the cylinder diameter below the sediment surface. Burial results, although variable, are in general agreement with the wave-induced scour model developed by Trembanis et al. (2007) for the fine sand, but not for the coarse sand where measured burial was much less than predicted.

Mine Burial in the Shoaling Zone: Scaling of Laboratory Results to Oceanic Situations

During the past several years, the Environmental Fluid Dynamics Group at Arizona State University (ASU, Tempe, AZ) conducted a comprehensive laboratory-based research program to elucidate the mechanisms and dynamics of mine burial in noncohesive sediments under shoaling waves on coastal slopes. This paper presents a brief description of this program as well as salient observations and quantitative parameterizations for scour, ripples, and burial that resulted from it (which constitute the ASU mine burial model). Improvements to mine burial predictive capabilities offered by the ASU model are demonstrated by evaluating it vis-a-vis the (legacy) mine burial models that are in common use [Defense Research Agency mine burial environment (DRAMBUIE), Industrie Anlagen Bau Gesellschaft (NBURY, Munchen, Germany), and wave-induced spreadsheet prediction (WISSP)]. To this end, both the legacy and ASU models are discussed briefly and compared with field experimental data obtained during the 2003 Indian Rocks Beach (IRB, FL) experiment. The scour/burial data collected during the IRB campaign, using instrumented mines and diver observations, show that the predictions of the mostly laboratory-based ASU model agree satisfactorily with field observations, both qualitatively and quantitatively.

Predicting Seabed Burial of Cylinders by Wave-Induced Scour: Application to the Sandy Inner Shelf Off Florida and Massachusetts

A simple parameterized model for wave-induced burial of mine-like cylinders as a function of grain-size, time-varying, wave orbital velocity and mine diameter was implemented and assessed against results from inert instrumented mines placed off the Indian Rocks Beach (IRB, FL), and off the Martha's vineyard coastal observatory (MVCO, Edgartown, MA). The steady flow scour parameters provided by Whitehouse (1998) for self-settling cylinders worked well for predicting burial by depth below the ambient seabed for (0.5 m) diameter mines in fine sand at both sites. By including or excluding scour pit infilling, a range of percent burial by surface area was predicted that was also consistent with observations. Rapid scour pit infilling was often seen at MVCO but never at IRB, suggesting that the environmental presence of fine sediment plays a key role in promoting infilling. Overprediction of mine scour in coarse sand was corrected by assuming a mine within a field of large ripples buries only until it generates no more turbulence than that produced by surrounding bedforms. The feasibility of using a regional wave model to predict mine burial in both hindcast and real-time forecast mode was tested using the National Oceanic and Atmospheric Administration (NOAA, Washington, DC) WaveWatch 3 (WW3) model. Hindcast waves were adequate for useful operational forcing of mine burial predictions, but five-day wave forecasts introduced large errors. This investigation was part of a larger effort to develop simple yet reliable predictions of mine burial suitable for addressing the operational needs of the U.S. Navy.

The onset of India–Asia continental collision: Early, steep subduction required by the timing of UHP metamorphism in the western Himalaya

Ultrahigh-pressure (UHP) rocks in the NW Himalaya are some of the youngest on Earth, and allow testing of critical questions of UHP formation and exhumation and the timing of the India–Asia collision. Initial collision of India with Asia is widely cited as being at 55 ± 1 Ma based on a paleomagnetically determined slowdown of India's plate velocity, and as being at ca. 51 Ma based on the termination of marine carbonate deposition. Even relatively small changes in this collision age force large changes in tectonic reconstructions because of the rapid India–Asia convergence rate of 134 mm/a at the time of collision. New U–Pb SHRIMP dating of zircon shows that Indian rocks of the Tso Morari Complex reached UHP depths at 53.3 ± 0.7 Ma. Given the high rate of Indian subduction, this dating implies that Indian continental crust arrived at the Asian trench no later than 57 ± 1 Ma, providing a metamorphic age for comparison with previous paleomagnetic and stratigraphic estimates. India's collision with Asia may be compared to modern processes in the Timor region in which initiation of collision precedes both the slowing of the convergence rate and the termination of marine carbonate deposition. The Indian UHP rocks must have traveled rapidly along a short, hence steep, path into the mantle. Early continental subduction was at a steep angle, probably vertical, comparable to modern continental subduction in the Hindu Kush, despite evidence for modern-day low-angle subduction of India beneath Tibet. Oceanic slab break-off likely coincided with exhumation of UHP terranes in the western Himalaya and led to the initiation of low-angle subduction and leucogranite generation.

New Locality Records for Dermophthirius carcharhini (Monogenea: Microbothriidae) and Dermophthirius maccallumi and a List of Hosts and Localities for Species of Dermophthirius

Abstract We report Dermophthirius carcharhini (Monogenea: Microbothriidae) from the skin of a dusky shark, Carcharhinus obscurus (Carcharhinidae), in the southwest Indian Ocean off Umhlanga Rocks, South Africa, and Dermophthirius maccallumi from the skin of 2 bull sharks, Carcharhinus leucas, in the northern Gulf of Mexico off Cat Island, Mississippi, U.S.A. No previous report exists of a microbothriid from the western Indian Ocean or from off southern Africa or of D. maccallumi from beyond the vicinity of the Lake Nicaragua–San Juan River system. We also provide a list of hosts and localities for members of Dermophthirius.

An overview of the stratigraphy and tectonics of the Nepal Himalaya

Nepal can be divided into the following five east–west trending major tectonic zones. (i) The Terai Tectonic Zone which consists of over one km of Recent alluvium concealing the Churia Group (Siwalik equivalents) and underlying rocks of northern Peninsular India. Recently active southward-propagating thrusts and folds beneath the Terai have affected both the underlying Churia and the younger sediments. (ii) The Churia Zone, which consists of Neogene to Quaternary foreland basin deposits and forms the Himalayan mountain front. The Churia Zone represents the most tectonically active part of the Himalaya. Recent sedimentologic, geochronologic and paleomagnetic studies have yielded a much better understanding of the provenance, paleoenvironment of deposition and the ages of these sediments. The Churia Group was deposited between ∼14 Ma and ∼1 Ma. Sedimentary rocks of the Churia Group form an archive of the final drama of Himalayan uplift. Involvement of the underlying northern Peninsular Indian rocks in the active tectonics of the Churia Zone has also been recognised. Unmetamorphosed Phanerozoic rocks of Peninsular India underlying the Churia Zone that are involved in the Himalayan orogeny may represent a transitional environment between the Peninsula and the Tethyan margin of the continent. (iii) The Lesser Himalayan Zone, in which mainly Precambrian rocks are involved, consists of sedimentary rocks that were deposited on the Indian continental margin and represent the southernmost facies of the Tethyan sea. Panafrican diastrophism interrupted the sedimentation in the Lesser Himalayan Zone during terminal Precambrian time causing a widespread unconformity. That unconformity separates over 12 km of unfossiliferous sedimentary rocks in the Lesser Himalaya from overlying fossiliferous rocks which are >3 km thick and range in age from Permo-Carboniferous to Lower to Middle Eocene. The deposition of the Upper Oligocene–Lower Miocene fluvial Dumri Formation records the emergence of the Himalayan mountains from under the sea. The Dumri represents the earliest foreland basin deposit of the Himalayan orogen in Nepal. Lesser Himalayan rocks are less metamorphosed than the rocks of the overlying Bhimphedis nappes and the crystalline rocks of the Higher Himalayan Zone. A broad anticline in the north and a corresponding syncline in the south along the Mahabharat range, as well as a number of thrusts and faults are the major structures of the Lesser Himalayan Zone which is thrust over the Churia Group along the Main Boundary Thrust (MBT). (iv) The crystalline high-grade metamorphic rocks of the Higher Himalayan Zone form the backbone of the Himalaya and give rise to its formidable high ranges. The Main Central Thrust (MCT) marks the base of this zone. Understanding the origin, timing of movement and associated metamorphism along the MCT holds the key to many questions about the evolution of the Himalaya. For example: the question of whether there is only one or whether there are two MCTs has been a subject of prolonged discussion without any conclusion having been reached. The well-known inverted metamorphism of the Himalaya and the late orogenic magmatism are generally attributed to movement along the MCT that brought a hot slab of High Himalayan Zone rocks over the cold Lesser Himalayan sequence. Harrison and his co-workers, as described in a paper in this volume, have lately proposed a detailed model of how this process operated. The rocks of the Higher Himalayan Zone are generally considered to be Middle Cambrian to Late Proterozoic in age. (v) The Tibetan Tethys Zone is represented by Cambrian to Cretaceous-Eocene fossiliferous sedimentary rocks overlying the crystalline rocks of the Higher Himalaya along the Southern Tibetan Detachment Fault System (STDFS) which is a north dipping normal fault system. The fault has dragged down to the north a huge pile of the Tethyan sedimentary rocks forming some of the largest folds on the Earth. Those sediments are generally considered to have been deposited in a more distal part of the Tethys than were the Lesser Himalayan sediments. The present tectonic architecture of the Himalaya is dominated by three master thrusts: the Main Central Thrust (MCT), the Main Boundary Thrust (MBT) and the Main Frontal Thrust (MFT). The age of initiation of these thrusts becomes younger from north to south, with the MCT as the oldest and the MFT as the youngest. All these thrusts are considered to come together at depth in a flat-lying decollement called the Main Himalayan Thrust (MHT). The Mahabharat Thrust (MT), an intermediate thrust between the MCT and the MBT is interpreted as having brought the Bhimphedi Group out over the Lesser Himalayan rocks giving rise to Lesser Himalayan nappes containing crystalline rocks. The position of roots of these nappes is still debated. The Southern Tibetan Detachment Fault System (STDFS) has played an important role in unroofing the higher Himalayan crystalline rocks.

Longshore Sediment Transport Rate Measured by Short-Term Impoundment

The total longshore sediment transport rate in the surf zone was measured at a temporary groin installed at Indian Rocks Beach, west central Florida. Approximate mass balance between updrift accumulation and downdrift erosion, which served as an indicator of reliability, was obtained in four of the six runs, which were subjected to further analysis. Magnitudes of three of the four transport rates were considerably lower than predictions by the Coastal Engineering Research Center formula calculated based on contemporaneous measurements of the breaking waves. Error analysis indicated that the determination of the longshore wave-energy flux factor carried a 22–48% maximum uncertainty, and the measured volume-change rate carried a 22–43% uncertainty. The combined uncertainties produce a 40–90% maximum uncertainty in determination of the empirical transport coefficient K appearing in the Coastal Engineering Research Center formula. Comparable or greater uncertainty in K-values probably exists in the total data...

The Patient in Room 321

Elaine Creasman, LPN,a freelance writer, has experience in orthopedic, medical and psychiatric nursing. She attends First Baptist Church of Indian Rocks in Largo, Florida, and just celebrated her nineteenth wedding anniversary.