Tectonics and Structure Commons^™

Geochemical Analysis Of Recent Volcanic Ash Blanketing Barbados And Constraints On Magma Composition (V32e-0112), Nazrul I. Khandaker, Krishna Mahabir, Surendranauth Mahabir, Lloyd Kiefer, Juan C. Campo, Andrew M. Singh

Publications and Research

Preliminary field and geochemical investigations were conducted on ash samples from Barbados to chemically characterize and decipher magma chemistry associated with a recent volcanic event. A thick plume of volcanic ash from the La Soufriere Volcano in St Vincent, which erupted on April 9, 2021, caused lower visibility due to ash clouds which engulfed the region for some time. Three authors from the research team visited Barbados during the summer subsequent and completed a reconnaissance investigation on recent ashfall. St Vincent is a small volcanic island in the Eastern Caribbean and lies in the southern part of the Lesser Antilles …

Integrating Remote Digital Tools Into Post-Pandemic Geologic Fieldwork To Effectively Disseminate Content Delivery And Assist In Overall Understanding Of Various Geologic Phenomena: Summer 2022 Field Mapping Exercises, Nazrul I. Khandaker

Publications and Research

INTEGRATING REMOTE DIGITAL TOOLS INTO POST-PANDEMIC GEOLOGIC FIELDWORK TO EFFECTIVELY DISSEMINATE CONTENT DELIVERY AND ASSIST IN OVERALL UNDERSTANDING OF VARIOUS GEOLOGIC PHENOMENA: SUMMER 2022 FIELD MAPPING EXERCISES

SHAMI, Malek, BETHEL, Cherise, NUNEZ, Eddy, RAYHAN, Salam, KHANDAKER, Nazrul and CABAROY, Charren C.

Geological Society of America Abstracts with Programs. Vol 54, No. 5, https://doi.org/10.1130/abs/2022AM-379779

SHAMI, Malek¹, BETHEL, Cherise², NUNEZ, Eddy³, RAYHAN, Salam³, KHANDAKER, Nazrul² and CABAROY, Charren C.¹, (1)Geology Discipline, AC-2F09, York College of CUNY, 9420 Guy R. Brewer Blvd., Jamaica, NY 11451, (2)Geology Discipline, York College of CUNY, …

Correlations Between The Rotations And Magnetospheres Of The Terrestrial Planets And The Sun's Formation In Our Solar System, Fred J. Cadieu

Publications and Research

Correlations between the rotations of the terrestrial planets in our solar system and the magnetic field of the Sun have been previously noted. These correlations account for the opposite rotation of Venus as a result of the magnetic field of the Sun being dragged across the conducting core of Venus. Currently the Sun’s magnetic field is not sufficiently strong to account for the proposed correlations. But recently meteorite paleomagnetism measurements have indicated that during the Sun’s formation the magnetic field of the Sun was of sufficient strength to have resulted in the observed correlations. As a part of these correlations …

Tectonic And Geotechnical Review Of Bengal Basin For Seismic Risk Assessment In Bangladesh, Mir Fazlul Karim, Jnana Ranjan Kayal, Daya Shanker, Nazrul I. Khandaker, Arif M. Sikder, M Zillur Rahman, Muhammad Qumrul Hassan

Publications and Research

Four major geotectonic provinces of the basin are recognized: 1) the continental slope to the west of the Hinge Zone, 2) the stable shelf, 3) the deep central trough (Sylhet-Hatiya) and 4) the Chittagong-Tripura fold belt to the east. The ~300 km long Dauki Fault demarcates the elevated Shillong Plateau, part of the Indian Shield to the north and the deep basin to the south. The basin experienced three strong to major intraplate earthquakes: a) 1885 Bengal earthquake (rev. Mw 6.8) close to the Hinge Zone, b) 1918 Srimangal earthquake (rev. Mw 7.1) on the Sylhet (trough) fault and c) …

Geologist Syed Humayun Akhter Is Leading The Bangladesh Open University, Nazrul I. Khandaker

Publications and Research

No abstract provided.

A Consistent Model Of Terrestrial Planet Magnetospheres And Rotations In Our Solar System, Fred J. Cadieu

Publications and Research

The Sun comprises 99.9% of the solar system mass so it is expected that Sun terrestrial planet interactions can influence the motion as well as the rotation of the terrestrial planets.Gravity affects the planet orbital motions while the changing magnetic fields of the Sun can influence the planet rotations. Planets that manifest a magnetic field dominate any weaker magnetic fields from the Sun, but the rotation of terrestrial planets without a magnetic field interacts with the changing Sun’s field dependent on the electrical conductivity of the core region. It is determined that the average planet density becomes a useful quantity …

Utilizing Dplot, Sedlog, And Arcgis Pro To Enhance Geologic Field Skills: Rosendale, Ulster County New York, Malek Shami, Nazrul I. Khandaker, Stanley Schleifer, Zarine Ali, Leonardo Sanchez, Gugu Ginindza, Tyn Tyn Nai

Publications and Research

Capstone geologic field mapping courses in undergraduate geoscience programs aim to compliment the academic knowledge with technical field skills. As a pilot study, these tools were used to collect field data using folded lower Paleozoic to mid-Paleozoic sedimentary outcrops consisting of clastic, non-clastic and occasional mixed siliciclastics in Rosendale, Ulster County, New York. Rosendale is known for its classic geological outcrops with variable structural, stratigraphic, paleontological and sedimentological complexities – ideal for a field mapping course. Traditionally, students’ data acquisition in the field and its subsequent laboratory analysis to produce a final geologic field report utilized acetate overlays to produce …

Further Study Of Garnet Xenocrysts In New York City Migmatites, Stanley Schleifer, Nazrul I. Khandaker

Publications and Research

The authors have previously published an article at the 2004 Geological Society of America Annual Meeting, Petrogenetic Significance of Garnets in the Bedrock of New York City, in which they suggested that the garnet xenocrysts observed in the quartzofeldspathic zones of the migmatites, so frequently seen both at the surface, and below the surface pursuant to the construction of the Manhattan portion of New york City Water Tunnel #3, were a refractory residue of the anatectic melting of the immediately surrounding schistose bedrock. Although the relatively high melting point temperature of garnet compared to other minerals in the surrounding …

Record Of Massive Upwellings From The Pacific Large Low Shear Velocity Province, Pilar Madrigal, Esteban Gazel, Kennet E. Flores, Michael Bizimis, Brian Jicha

Publications and Research

Global tomography and numerical models suggest that mantle plume occurrences are closely linked to the margins of large low-shear velocity provinces (LLSVPs)1–4. In these marginal zones the ascent of material from the core-mantle boundary connects deep mantle dynamics with surface processes through mantle plume activity, forming large igneous provinces (LIPs) and some of the modern hotspot volcanoes5,6. Petrological7 and geodynamic8 evidence suggest a link between the formation of oceanic plateaus and the interactions of mantle plumes and mid-ocean ridges (MORs). Even though the causality relationship between both processes is still unclear (either rifting is initiated by plume impact or it …

A College Level Geology Field Trip In Western Connecticut And Vicinity, Stanley Schleifer, Nazrul I. Khandaker, Keshaw Narine, Ezazul Haque, Ratan Dhar

Publications and Research

There are a number of excellent locations for field exposure for college students in, and around Western Connecticut. These are accessible for a one day field trip within striking distance of New York City, Bridgeport and New Haven, CT and other nearby locations. They are also suitable for an expanded weekend field trip. The field locations include; Kent Falls State Park, Kent, CT, Dinosaur State Park, Rocky Hill, CT, the Hubbard Mining Museum, Kent, CT, Bash Bish Falls in Mt. Washington, Massachusetts, Macedonia Brook State Park in Kent, CT and various outcrops exposed along U. S. Route 7 north of …

Sedimentology Of The Upper Scotland Formation (Eocene), Barbados, Krishna Mahabir, Nazrul I. Khandaker, Jay P. Persaud, Stanley Schleifer

Publications and Research

Representative samples collected from the Lower Scotland Formation (Eocene) outcropping in northeastern Barbados were investigated in conjunction with overall facies distribution and stratigraphic and sedimentological characteristics to interpret depositional environment and provenance of the fine-grained clastics. The Lower Scotland Formation is, for the most part, a fine-grained clastic-dominated sequence with occasional thin intercalations of gypsum, ironstone, and kaolinite. Distinctive deep-water-facies have been well-documented in dark gray shale units containing load cast, flutes, grooves and prods. In addition, turbiditic brown sandstone with a sharp erosive base and pelagic caps also characterize the base of the formation. Notable marine fauna observed include …

An Apparent Angular Unconformity In Western Connecticut, Stanley Schleifer, Nazrul I. Khandaker, Adisa Charles, Hernando Martinez, Shirley Jackson, Chiemeka Ihebom

Publications and Research

The recent extension, to the north, of the U. S. Route 7 ‘superhighway’ in the town of Brookfield, Connecticut has involved the excavation of crystalline bedrock of lower Paleozoic to upper Proterozoic age in the area. The road cuts produced by this excavation have exposed some interesting features of structure and lithology. An outcrop, observed by the authors off the east side of route 7, at grid coordinates 41.482444 N, 73.415307 W is of particular interest. It appears, to the casual observer to be an angular unconformity. Maps and publications regarding this area of Western Connecticut support the likelihood of …

Tectonosedimentologic Significance Of The Upper Cretaceous Foreland Basin Siliciclastics: Western Interior, Usa, Nazrul I. Khandaker

Publications and Research

The Upper Cretaceous Frontier Formation exposed along the western margin of the western interior foreland basin is composed of clastic sediments that were deposited during the initial late Cretaceous transgressive-regressive phases of the Western Interior Seaway across Wyoming (Figure 1). Current study is aimed at providing attendees with the best practices associated with tectonic, lithofacies and sedimentologic interpretation of foreland basin sequences and emphasizing the need for utilizing field, structural, geochemical, and compositional data for reconstructing a viable scenario connected with foreland basin sedimentary packages. An attempt will be made to compare documented sedimentological findings with foreland basins located in …

Tectonics And Sedimentary Facies Interpretation Of The Mesozoic Giron Group, Colombia, Hernando Martinez-Sacristan, Ricardo Mier-Umana, Nazrul I. Khandaker, Stanley Schleifer, Diana Lucia Leon-Martinez

Publications and Research

Preliminary field investigations involving exposed Giron Group sediments in Colombia provided some interesting geologic information in terms of provenance, depositional environments, and development of the Mesozoic synrift sedimentary basins in Colombia. Overall, the synrift Triassic-Jurassic rift-related volcanic rocks, redbeds, and evaporites are prominent in Colombia, and a thick basin sequence of Cretaceous sandstones and shales dominates the central part of the Cordillera Oriental. These were mostly deposited in dominantly north-trending grabens. Identified sedimentary rock types were arkose, clast-and-matrix-supported conglomerate, red mudstone, variegated sandstone, siltstone and breccia. Extensive kaolinitization was noticeable in several sandstone samples. Among the notable sedimentary structures were …

Dissemination Of Geological Information In Avoiding Geotechnical Risks Associated With Tunnel Construction: Lessons Learned From Deep Voids In Marble In Lower Manhattan, New York City, Nazrul I. Khandaker, Stanley Schleifer, Masud Ahmed, Leah Scott

Publications and Research

Test boring associated with the recently accomplished City Water Tunnel # 3 in Manhattan, New York City revealed moderately to highly weathered marble with insoluble silicate residues composed mostly of phlogopite, chlorite, and tremolite. Apparent control on the weatherability of the marble was in response to original mineral constituents dominating this lithology. Encountered marble samples ranged between pure calcitic to mixed dolomitic/siliceous types. Fresh marble samples collected from adjacent boring locations revealed characteristic geochemical data: Lime (25-45%), Silica (4-7%), Alumina (1-3%), MgO (5-20%), and LOI (35-42%); compressive strength of unweathered marble varied between 2000-3000 Kg/cm². Relict foliations with …

Upper Cretaceous Peay Bentonites (North-Central Wyoming): Provenance And Tectonics Interpretation From Ash Composition, Nazrul I. Khandaker, Carl F. Vondra, Karl E. Seifert, Malek Shami, Rochelle Cardinale, Thakur Chaturgan

Publications and Research

The Peay bentonites belong to the basal Frontier Formation (Bighorn Basin, north-central Wyoming), primarily outcrop in the Bighorn Basin, rest on an extensively bioturbated sandstone unit, the Peay Sandstone, and are generally the thinner bentonitic unit. Beds of very light gray to greenish gray bentonite are also abundant in the lower Frontier units between Kaycee and Mayoworth (Powder River Basin) and are very rarely as much as 3 m thick. Bentonite occurs within the interstratified shale, sandstone, and siltstone sequences of the lower Frontier unit throughout much of the southwestern Powder River Basin. The purpose of this study is to …

Tunnel Geology As Seen By Geologists: Manhattan, New York City, Nazrul I. Khandaker, Stanley Schleifer, Masud Ahmed, Alan R. Slaughter, Belal A. Sayeed, Dorean J. Flores, Mario Jo-Ramirez

Publications and Research

Current exploratory boring operations in and around Manhattan, New York City are providing geologists and geotechnical engineers with a plethora of new and interesting geological information, which has not been previously reported. The rocks encountered, mostly medium to high-grade metamorphic rocks, with both mafic and felsic intrusives, are highly variable in competency and mechanical durability. One of the most frequently encountered rock types is a garnetiferous-muscovite-biotite schist which grades into schistose gneiss and displays a wide variety of structural, compositional, and textural attributes. Metamorphic minerals showing the variable degree of metamorphism include graphite, talc, garnet, kyanite, tourmaline, emory, and occasionally …

Microanalytical Investigations Of Gold-Bearing Rocks From The An Najadi Region In Saudi Arabia, Nazrul I. Khandaker, M. Ahmed, M. M. Hariri, M. A. Garwan, K. R. Khan, M. M. Al-Ohali

Publications and Research

The Proton Induced X-ray Emission technique with a scanning microbeam (micro-PIXE) and Scanning Electron Microscopy (SEM) were employed to study gold-bearing rocks from the An Najadi and adjacent regions situated within the exposed northeastern part of the Arabian Shield. These microanalytical investigations, together with routine petrological and ore microscopic studies, demonstrated the presence of important partitioning of major minerals and trace elements in several samples. These measurements also revealed microstructural features including brecciation within quartz grains and metal concentrations within these fracture-controlled micro-conduits. Results showed promise in terms of using distinctive geochemical signatures for ore body recognition. Of particular interest …

Study Of Volcanic Sediments By Microbeam-Pixe Technique, Nazrul I. Khandaker, M. Ahmed, M. A. Garwan

Publications and Research

Single mineral grains in a suite of Cretaceous (85–90 Ma) volcanic sedimentary rocks were analyzed using the microbeam-PIXE technique to understand fundamental geological processes responsible for micro-scale variation in elemental composition across mineral zones, twinning, cleavage planes, fractures and grain boundaries. Distributions of major and trace elements show distinct geochemical features indicative of a specific geological setting and a subsequent diagenetic process in these volcanic sediments. Examples of mineral zoning, microstructures of variable chemistry and post-depositional fluid flow are discussed using the data on feldspar group of minerals.

La Deriva De Los Continentes, Aldemaro Romero Jr.

Publications and Research

No abstract provided.