Physical Sciences and Mathematics Commons^™

Guidance Index For Shallow Landslide Hazard Analysis, Cheila Cullen

Dissertations, Theses, and Capstone Projects

Rainfall-induced landslides are one of the most frequent hazards on slanted terrains. They lead to considerable economic losses and fatalities worldwide. Intense storms with high-intensity and long-duration rainfall have high potential to trigger rapidly moving soil masses due to changes in pore water pressure and seepage forces. Nevertheless, regardless of the intensity-duration of the rainfall, shallow landslides are influenced by antecedent soil moisture conditions. To the present day, no system exists that dynamically interrelates these two factors.

This work establishes a relationship between antecedent soil moisture and rainfall expressed in the form of a Shallow Landslide Index (SLI) at 1km …

An Iterative Approach To Ground Penetrating Radar At The Maya Site Of Pacbitun, Belize, Sheldon Skaggs, Terry G. Powis, Clara R. Rucker, George Micheletti

Publications and Research

Ground penetrating radar (GPR) surveys provide distinct advantages for archaeological prospection in ancient, complex, urban Maya sites, particularly where dense foliage or modern debris may preclude other remote sensing or geophysical techniques. Unidirectional GPR surveys using a 500 MHz shielded antenna were performed at the Middle Preclassic Maya site of Pacbitun, Belize. The survey in 2012 identified numerous linear and circular anomalies between 1 m and 2 m deep. Based on these anomalies, one 1 m × 4 m unit and three smaller units were excavated in 2013. These test units revealed a curved plaster surface not previously found at …

Effective Integration Of Nasa Stem Curricula Is Allowing Students To Appreciate Earth Science Concepts, Nazrul I. Khandaker, Stanley Schleifer, Krishna Mahabir, Newrence Wills, Matthew Khargie

Publications and Research

NASA Minority University Research and Education Project (MUREP) Aerospace Academy - MAA is a national, innovative activity designed to increase participation and retention of historically underserved and underrepresented K-12 youth in the STEM disciplines, particularly earth science and human exploration (HEO). HEO is dedicated to informing and educating the public about NASA's plans for a new era in space exploration. Utilization of NASA satellite images, online climate education, space mathematics and other earth science-related resources is allowing students to conduct basic research and prepare themselves for a New York City-wide science competition. In addition to offering school children a solid …

Surficial Geology Of York College Campus (Queens) And Montauk Point (Long Island): An Open Access To Geoscience Education, Nazrul I. Khandaker, Stanley Schleifer, Krishna Mahabir, Erik Menjivar, Ality Aghedo, Dennis Baidoo, Tenzin Choeying, Vanessa Erwin, Jonathan Xavier, Laboni Molla, Akeed Alrubay

Publications and Research

To evaluate compositional and textural differences among the samples collected from York College (YC) campus (Queens), Montauk Point (MP) and Hither Hills (HH), Long Island, emphasis is given to the general geologic setting, overall grain size distribution, and relative abundances of light and heavy mineral assemblages. Geologic setting encompasses outwash plains (York College), fluvioglacial and glacial (Montauk Point) and beach and dune complex (Hither Hills). YC samples were collected from depth ranging 40 cm to 250 cm and are mostly an assortment of medium to coarse sand, granule to cobble sized, minor silt, and clay. Presence of low angle cross …

Experiential Learning Opportunities Through Nasa Stem Content Allows Greater Grass Root-Level Understanding Of The Present Day’S Extreme Climate Change Scenario, Nazrul I. Khandaker, Stanley Schleifer, Matthew Khargie

Publications and Research

The NASA MAA (MUREP Aerospace Academy) project at York College has demonstrated a track record of providing experiential learning opportunities (ELO) to its participating students. ELOs associated with MAA are designed to increase learners’ involvement, knowledge, comprehension and application of learning in one or more STEM subjects/disciplines. They involve inquiry-and-activity-based learning approaches designed for the level of the learner to inspire, engage, and educate while progressively challenging each student. ELO activities enable learners to acquire knowledge, understand what they have learned, and apply that knowledge through inquiry-based tasks. Specifically, we are prepared to address the following priority: Encourage, increase, and …

Montauk Point, An Essential Field Experience For Students In The New York City Area, Stanley Schleifer, Nazrul I. Khandaker, Keshaw Narine

Publications and Research

Except for a thin strip of Proterozoic and Paleozoic metamorphic and igneous rock along its very western edge and an outcropping of coastal plain deposits along its northwestern edge, the surface of Long Island is immediately underlain by unconsolidated deposits consisting of moraines of glacial till, outwash plains of stratified drift, and beach and dune complex formed by wave action. Two very prominent features of the island are the Harbor Hill Moraine, which marks the southernmost extent of the last major advance of continental glacier ice in the New York area during the Pleistocene and the Ronkonkoma Moraine, which marks …

Bathymetric Survey For Lakes Azuei And Enriquillo, Hispaniola, Michael Piasecki, Mahrokh Moknatian, Fred Moshary, Joseph Cleto, Yolanda Leon, Jorge Gonzalez, Daniel Comarazamy

Publications and Research

The two largest lakes on the Caribbean Island of Hispaniola, Lake Azuei in Haiti and Lake Enriquillo in the Dominican Republic, have experienced dramatic growth and surface area expansion over the past few years leading to severe flooding and loss of arable land around the lake perimeters. In order to better understand the reasons for this unprecedented rate of expansion and the resulting consequences a multi-disciplinary team comprised of researchers from Haiti, the DR, and the US have embarked on an extensive data collecting and hydrologic and climatological modeling campaign. While the sensor deployment entails stations that measure climatological data …

Improving Landslide Hazard And Risk Mapping In Guatemala Using Terrain Aspect, Yuri Gorohkovich, Elia Axinia Machado, Luis Ivan Giron Melgar, Mahta Ghahremani

Publications and Research

Guatemala is in the path of numerous atmospheric hazards that trigger landslides by saturating mountain slopes with water reducing their safety factor. Available local studies of landslide characterization in Guatemala have indicated the importance of slope in hazard and risk mapping, but, for the most part, ignored another topographic index: aspect. However, many regional studies analyzing the effect of hurricanes on terrain show that Caribbean and Central American locations experience higher impact from hurricanes and storms on eastern, southeastern, southern and southwestern slopes. Since hazard and risk mapping focuses on infrastructure and settlements located on slopes with various orientations, this …

Analyzing Evapotranspiration In The Tropical Montane Cloud Forest At Sierra De Bahoruco, Dominican Republic, Emmanuel Rodriguez-Gonzalez

Dissertations and Theses

Lake Enriquillo is located in the southwestern extreme of Dominican Republic and has been experiencing a rapid expansion in surface area, along with other water bodies in the same region, since 2004 causing major flooding to the surrounding agricultural and cattle-raising lands, infrastructure and communities. Understanding why the lake is expanding at such rapid rate and accurately forecast how they will behave in the future is the main goal of The Hispaniola Lakes Project. The purpose of this project is to investigate the effects that hydrometeorological drivers are having on the forested areas located in Sierra de Bahoruco, which is …

Modern Foraminiferal Assemblages Of The Denmark Strait, Laura Larocca

Dissertations and Theses

Foraminifera occupy a geological range from the early Cambrian to the present day. Their well preserved shells, high relative abundance, and short response time to changing environmental conditions make foraminifera ideal proxies for environmental change. Benthic foraminifera are a valuable but poorly understood paleobiological proxy for the reconstruction of environmental conditions on continental shelves occupied by arctic and subarctic waters. This study identifies, examines, and quantifies calcareous benthic foraminiferal faunas from a sediment core taken from the Denmark Strait. Our analysis of three-thousand individuals from ten discrete samples aim to provide a better understanding of the modern patterns of foraminiferal …

Assessing The Utility Of Imaging Radar For Identifying White Sand Vegetation Structure, Jessica Rosenqvist

Dissertations and Theses

White sand vegetation communities are wide spread across South America; found in Peru, Venezuela, Brazilian Amazon and Guyana. They are distributed in patches ranging from <1 km2 to greater than tens of square kilometers and their origins and locations are still not well understood. The communities are related to a variety of factors (soil type, flooding, nutrient content and fire); hence a precise definition for the ecosystem is still not fully defined. Nevertheless, the result of these variations creates a unique environment for endemic plant and animal species to thrive. Furthermore, analysis of these areas has been very scattered and identification of local white sand areas (<1 km2) have not been accomplished. In addition, identification of these locations has currently only used optical satellite imagery (Landsat, MODIS). Hence, in this project, we have attempted to use synthetic aperture radar to create a classification system to locate the white sand vegetation systems. The goal is to be able to apply this method to identify white sand vegetation distribution across South America. The region of focus for this thesis has been in Aracá, a large white sand area located in Brazil in the State of Amazonas. Due to the lack of ground reference data, a classified map by Capurucho et al. (2013), generated using Landsat data, was used as a comparison and reference. JAXA’s ALOS-1 PALSAR (L-band), ESA’s Sentinel-1A (C-band) and NASA’s SRTM sensors were used for land classification. As microwave signals penetrate clouds and haze, the advantage of using sensors with this wavelength allows for an unobstructed coverage of the landscape all year round. Different combinations of polarizations and wavelengths were used during the analysis to try and separate the white sand vegetation from water and terra firme forest. The resulting classification images showed a 30% agreement with the classification map by Capurucho et al. It is important to note, that this number is in fact an agreement percentage as the map used was a classification image and coarse in resolution (due to the lack of reference data). Therefore, this value does not imply a bad classification. Future work will include time-series data, precise ground reference points and data from other sensors such as ALOS-2 PALSAR, to improve the classification accuracy.

The Bou Dahar Jurassic Carbonate-Hosted Pb–Zn–Ba Deposits (Oriental High Atlas, Morocco): Fluid-Inclusion And C–O–S–Pb Isotope Studies, Larbi Rddad, Salah Bouhlel

Publications and Research

The Bou Dahar Pb–Zn–Ba (±Sr) is hosted in the Lower and Middle Liassic carbonate platform in the oriental High Atlas of Morocco. The paragenetic sequence includes quartz–pyrite–melnicovite–sphalerite–galena– calcite–barite ± fluorite– ± celestite. Fluid-inclusion studies were conducted on sphalerite (early mineralizing stage) and barite, and celestite (late mineralizing stage). These studies reveal two end-member fluids, a hot (~143 °C) and saline fluid (~23 wt.% NaCl eq.) and a cooler (b50 °C) and diluted fluid (~5 wt.% NaCl eq.). Based on fluid-inclusion and C–O–S isotope studies, a conclusion is reached that the Bou Dahar ore deposits were formed by the mixing of …

3d Structural And Stratigraphic Architecture Of The Northwest Santa Barbara Basin And Implications For Submarine Landslide Generation, Alexis Wright

Dissertations and Theses

Multiple submarine landslides have been previously documented on the north flank of the Santa Barbara Channel, and such failures are considered to be capable of generating local tsunamis hazards to the Santa Barbara region. 2D seismic-reflection datasets provide a general view of regional framework geology, including faulting and folding associated with north-south compression. However, better understanding of the relationships between faults, folds, stratigraphic architecture, and submarine landslides can be obtained with 3D seismic datasets. In this study we use an industry 3D seismic-reflection volume that encompasses the slope and shelfbreak surrounding the Gaviota submarine landslide (3.8 km2) to investigate structural …