All images on this page:  Dukelabs.com © 2006

27 October 2006

New Geological Discoveries in Southern Manhattan

Dr. Merguerian spoke at the 3rd Annual Hofstra University Natural Science Research Symposium on his field work and analysis of southern New York City.

Abstract:

Drill core examined from over two dozen separate locations south of Canal Street in Manhattan over the past three years have been fruitful in extending surface mapping from areas of natural exposures north of 59th Street.  In this area of no surface exposure, drill core and other forms of subsurface information indicate that the region is underlain by internally sheared units of the Walloomsac, Manhattan, and Hartland formations together with sheared slivers of serpentinite and foliated granitoid rock.  This work supports the contention that the venerable Manhattan Schist formation actually consists of three schistose units, now mapped as the Hartland, Manhattan, and Walloomsac formations.  These lithostratigraphic units have different paleogeographic origins.  In addition, a newly discovered belt of schistose and calcareous rocks appears south of Canal Street in NYC in two separate along strike areas near the World Trade Center site and also reappears across town near the Brooklyn Bridge.  Exposed as a result of new construction efforts, the duplication of hitherto unrecognized Walloomsac rocks on either side of southern Manhattan suggests repetition by folding and/or faulting.

26 September  2006 

New Insights into the Structural Geology of NYC

A post-luncheon presentation at the Mineral Sciences Department of the American Museum of Natural History by Dr. Charles Merguerian focused on new discoveries from construction sites in NYC.  Recent work in collaboration with Cheryl Moss of Mueser-Rutledge Engineers indicates that in southern Manhattan duplication of a continuous belt of sheared Hartland schist and granofels and Walloomsac graphitic schist and calc-silicate rocks occurs in a tract where aluminous rocks of the Manhattan formation were anticipated.  Based on new data concerning the distribution of serpentinites and a wealth of existing data from historic construction efforts, new insights and interpretations of the structural geology and tectonics of the region were discussed.  A highly spirited question and answer period delighted all attendees.

09 May 2006

Mega-Construction Projects in New York City

Dr. Merguerian presented an animated lecture at the annual dinner of the Stamford Mineralogical Society in early May.  His talk described new tunneling contracts in the City of New York including elements of the Third NYC Water Tunnel, the Second Avenue Subway, the East Side Access project, and the #7 Line Extension.  He discussed new discoveries in deep tunnels that have changed our views of the geology of New York City and show examples of minerals found during mapping of the Queens Tunnel.

In the past decade, Merguerian's research has strayed to include geologic mapping and analysis of tunnels bored by tunnel boring machines (TBMs).  This work has verified geological relationships established by surface mapping and has provided new insights into the relationships between TBM penetration rates, geological structure, and rock type in the New York City area.  Geotechnical research, along with engineering, have evolved efficient methods in constructing water, utility, and transportation tunnels in urban areas.

Structural Implications of Walloomsac and Hartland Rocks Displayed by Borings in Southern Manhattan

A joint paper presented by Charles Merguerian (speaker) and Cheryl Moss focused on a new discovery of a continuous belt of Walloomsac graphitic schist and calc-silicate rocks in an area of Manhattan where aluminous rocks of the Hartland formation were expected.  Always on the look-out for the unusual, Merguerian and coauthor Cheryl Moss of Mueser-Rutledge Consulting Engineers have spent countless afternoons examining drill core and construction excavations and have found the presence of calcareous and graphitic rocks based on their investigations.  They will report on their findings and the implications for the bedrock map of Manhattan.  This paper was presented at the 13th Annual Meeting of the Long Island Geologists.  

22 April  2006

Evidence for Multiple Glacial Advances and Ice Loading From a Buried Valley in Southern Manhattan

Cheryl Moss (speaker) and Charles Merguerian presented a paper on a newly discovered NW-trending buried valley in southern Manhattan that holds evidence for multiple glaciations is slated for the 13th Annual Meeting of the Long Island Geologists.  Always on the look-out for the unusual, Cheryl Moss of Mueser-Rutledge Consulting Engineers and coauthor Charles Merguerian of Hofstra University have found serpentine-pebble basal till overlain by additional glacial drift units.  They will report on their findings and the support for the multi-glacier hypothesis for New York and vicinity.

 22 April  2006

Orchard Beach Ultramafic Erratics – Where Are They From?

Drs. Nehru E. Cherukupalli (Speaker) and Charles Merguerian presented a joint paper on the preliminary results of their petrographic and geochemical analysis of three separate and seemingly unique ultramafic erratics found on striated bedrock at Orchard Beach, NY.  The presentation is slated for late April at the 13th Annual Meeting of the Long Island Geologists.  

View of mechanically weathered ultramafic boulder, one of three analyzed in this pilot study.  Digital image by N. E. Cherukupalli (2005).

16 April  2005

Newly Discovered Ophiolite Scrap in the Hartland Formation of Midtown Manhattan

Dr. Charles Merguerian delivered a joint paper at the Twelfth Annual Meeting of the Long Island Geologists on a new discovery of a mass of sheared serpentinite in midtown Manhattan.  Always on the look-out for the unusual, Merguerian and coauthor Cheryl Moss of Mueser-Rutledge Consulting Engineers spent four afternoons examining the geology and contact relationships of a small, highly deformed and elongated serpentinite body that has been uncovered in a deep building construction site at 43rd Street and Sixth Avenue in midtown Manhattan.  Serpentinites are black to greenish-black, fine-textured rocks containing serpentine group minerals including chrysotile, lizardite, and antigorite together with amphiboles, chlorite, brucite, magnesite, talc, calcite, and relict chromite, magnetite, olivine and pyroxene.  Similar to the famous Staten Island and Hoboken NJ serpentinites, many scattered bodies of serpentine rock have been encountered in the subsurface of NYC over the years as a result of construction.  In addition to the legendary mass known from Manhattan between 54th and 62nd Streets along the shore and 10th Avenue (Cozzens 1843; Gratacap 1887), a few bodies were penetrated by borings in the geotechnical investigation stages of the #7 Line extension in Manhattan and in train tunnels excavated beneath the Hudson River.  The joint paper makes a comparison between Appalachian serpentinites and those of the Coast Ranges of California, suggesting that they originated in a similar tectonic setting.

View toward the SSE (Bryant Park in distance) of the One Bryant Park site showing the early stages of the excavation.  Digital image taken 21 December 2004.

Loading Patterns in Varved Pleistocene Sediment in the NYC area

Another joint paper, this one presented by Cheryl Moss of Mueser-Rutledge Consulting Engineers was also presented at the Twelfth Annual Meeting of the Long Island Geologists.  Her work on the loading of Pleistocene lake strata shows a systematic geographical distribution pattern that may indicate where younger glacial ice once over-rode pre-deposited lake strata.  Although preliminary at the present time, such data may prove beneficial in establishing the thickness, scope, and extent of the Woodfordian glacier and help to support the multi-glacier hypothesis of Sanders and Merguerian (1998).

Surficial geological map of northern New Jersey with locations of additional sites studied in the New York and New Jersey area.  The numbers indicate the average amount of overconsolidation (in tsf) for non-desiccated soils at each of the locations (x).  D indicates only desiccated samples were tested; N indicates the soil is normally consolidated under the existing overburden.   (Figure 5; Moss and Merguerian, 2005.)

Post-Alleghenian Deformation of the Shawangunk Ridge in NY and NJ

Based on a research trip with Hofstra University structural geology students led late last year (2004), new field data supports the idea that deformation of the Shawangunk ridge in NY and NJ may be of Mesozoic age.  At High Point State Park in NJ, the Shawangunk strata is overturned and changes in strike away from typical non-Appalachian trends.  The geometry of the structures forces the conclusion that deformation was the result of right lateral shear, perhaps resulting from an early stage of opening of the Atlantic ocean basin.  In a joint paper at the Twelfth Annual Meeting of the Long Island Geologists, Hofstra University students Jeff Wills, John Bigolski, and Charles Merguerian share some new ideas on the age and style of Appalachian deformation saw the light of day in poster form.

Scanned 35 mm Kodachrome taken from commercial flight over Harrisburg, PA, showing folded strata typical of the Valley and Ridge physiographic province of the Appalachians.

08 April 2005

Applications of Geology to Mega-Construction Projects in New York City

Merguerian delivered a keynote after-dinner candle-lit talk to research students attending the Colonial Academic Conference at Hofstra University in April 2005.  His lecture was based on research which has concentrated on geologic mapping of tunnels bored by tunnel boring machines (TBMs).  This work has verified geological relationships established by surface mapping and has provided important new insights into the relationships between TBM penetration rates, geological structure, and rock type in the New York City area.  His research has paved the way for more efficient tunneling in crystalline terrains and has opened the field for municipal mega-construction projects including water, utility, and transportation tunnels.  His talk focused on new tunneling contracts in the City of New York including the Third NYC Water Tunnel, the Second Avenue Subway, the East Side Access project, and the #7 Line Extension.

05 March 2005

Geology of the Painted Desert and Petrified Forest, AZ

Awed by a visit to the region in July 2004 with his assistant Mickey, the elder Merguerian spoke at the New York Mineralogical Club Mineral Show about the landscape formation and geology of the Painted Desert and Petrified Forest region of northeastern Arizona.  In the 1800s, U.S. Army map makers and surveyors described the "Painted Desert" and its trees turned to stone.  Here, the geologic history of the region peaks during Mesozoic time - an era when dinosaurs ruled the earth.  After growing to great height and thickness, the tall trees fell and were washed by swollen streams into a broad floodplain.  There they were covered by silt, mud, and volcanic ash, and this blanket of deposits cut off oxygen and slowed the logs decay. Gradually, silica-bearing ground waters seeped through the logs and encased the original woody tissue with silica.  Slowly the process continued, the silica crystallized into quartz, and the logs were preserved as dense, multi-hued petrified wood.  Images of these magnificent petrified logs and video clips of the region adorned the Powerpoint presentation on this unique area. 

All images on this page:   © Dukelabs.com

05 November 2004

Teaching Geology in New York City Parks

Dr. Merguerian spoke to the Education Section of the New York Academy of Sciences to end the 2004 lecture circuit on the subject of utilizing New York City parks to teach inquiry based geological education.  His lecture focused on the bedrock and glacial features exposed in Central and Inwood parks in Manhattan, the New York Botanical Garden, and some smaller parks in the Bronx that best illustrate his methodology of teaching geology in New York City.  Participants, many of whom were tired from teaching at their day job, brought ripe vegetables and limber throwing arms for some big lecture fun.  Digital image of Merguerian coming to grips with his understanding of the geology of New York City.

All images on this page:  © Dukelabs.com

21 October 2004

12 Million Thirsty People:  Supplying New York City and Long Island with Fresh Water

Most of New York City and all of Long Island are, in fact, islands surrounded by salt water.  So how do we get enough fresh drinking water to supply 12 million thirsty people and their dehydrated pets?  Speaking for the IDEAS Institute Lectures Series at Hofstra University, Dr. Merguerian diagrammed how Long Island sits above trillions of gallons of fresh groundwater that is pumped to the surface for drinking water and how, by contrast, New York City relies on a system of gravity-feed pressure tunnels to bring fresh water from reservoirs over a hundred miles away in the Catskills.  These huge water tunnels and their distribution systems constitute the greatest engineering work of our Twentieth century (and let's face it - what a century it was!).  Participants (thanks Mabel, for showing up) were treated to a video-laced Powerpoint presentation that took them deep under the city inside a water tunnel constructed beneath Queens, Brooklyn and now in Manhattan.  Digital Image of early field work by Merguerian in the City of New York, demonstrating his long-standing commitment to the "glory days" of mapping before 15 km of uplift and erosion took place.

All daguerreotypes  on this page:  Dukelabs.com © 200 Million Years ago

15 October 2004

Geotechnical investigations specific to the Narrows provide the tantalizing interpretation that an episodic breach took place through the Harbor Hill moraine that drained the meltwater lakes and eroded the Narrows channel.  Subsurface information compiled from multiple sources indicates that two tills, outwash fans, and varved lake strata form a continuous blanket of regolith in the NY Harbor area and support a multi-glacier hypothesis for the region.  Varved lake clays provide evidence that the Harbor Hill moraine acted as a dam, impounding glacial lakes in the Hudson Valley.  In a brief cameo appearance (10 minutes), Professor Merguerian spoke at the Divisional Natural Sciences Research Day at Hofstra University to explain, to a small but stunned audience, how such an event could have redirected the flow of the ancestral Hudson River across the Upper New York Bay into its modern course.  Digital image from commercial flight showing the modern Narrows channel.  Note on left hand side of roadway, Merguerian beating the eastbound toll on the Verrazano Narrows bridge.

All images on this page:  Dukelabs.com © 2005

08 September 2004

Geology of California and the Mother Lode Gold Belt

Dr. Charles Merguerian of Hofstra University and Duke Geological Laboratories spoke to the New York Mineralogical Club at the Museum of Natural History.  Based on experience mapping in the foothills gold belt of the Sierra Nevada, he described a west to east transect view of the geology of the state and then focused on the geology and history of the Mother Lode gold belt.  With first-hand knowledge and an extensive line of bull as a composite resource, his video-enhanced Powerpoint lecture featured images of many crystalline gold specimens found in the area of the Mother Lode.  Digital image of Merced River drainage.

Geology of Central Park - From Rocks to Ice

At the eleventh annual meeting of the Long Island Geologists, Charles Merguerian spoke about the joint research project conducted with Dukelabs advance scout Mickey in late 2003.   New lithologic mapping has redefined the extent of aluminous rocks mapped as Hartland formation throughout Central Park.  Their fully extended 24 p. abstract (Merguerian and Merguerian, 2004) includes a Field Trip to the south part of the park, the area most visited by travelers and tourists.  Such a trip was conducted on 26 June 2004 for the Long Island Geologists by the authors.  Digital image of Central Park and Manhattan island from the window of a commercial jet by señor author.

All  images on this page:  Dukelabs.com © 2005

Brittle Fault Chronology of New York City

At the Northeastern Sectional Meeting of the Geological Society of America in Tysons Corner, VA this year, Hofstra University Professor and Dukelabs geologist Charles Merguerian discussed the chronology of the brittle faults of New York City, pointing to evidence of neotectonic activity along NNW and NW-trending faults.   His geomorphic analysis of the McCoun topographic map of 1609 (reproduced below) indicates the presence of numerous through-going faults of the type that have shown recent seismicity.  The epicenters of two 2001 earthquakes are shown as red dots.

All  images on this page:  Dukelabs.com © 2005

Topographic map of Manhattan by McCoun (1609) showing the pre-industrial era drainage patterns.  Drainages follow zones of structural weakness in crystalline rocks, typically faults.  The pronounced NNW-SSE alignment of creek and stream valleys is striking.  The right panel shows the traces of three mapped faults in Central Park (faults showing offset symbols), other inferred faults based on stream patterns and topography, and epicenters of two small tremors that struck Manhattan Island in 2001.  Note that the vertical edge of the figure is oriented N29°E.   (From Merguerian and Merguerian, 2004; Figure 7.)

21 February 2004

All  images on this page:  Dukelabs.com © 2005

Geology of the NYC Water Tunnel System

Dukelabs geologist and Hofstra University Professor Charles Merguerian discussed the geology of the NYC aqueduct system paying particular attention to the distribution tunnels beneath NYC.  His Powerpoint talk focused on the results of over 25 years of research in the water tunnel system showing many subsurface views.  The subsurface data has helped verify Merguerian's surface mapping and points to the presence of hitherto unknown rock units, ductile- and brittle faults, and volcanic rocks, never before found in NYC.

 

Seminar Lecture for the Department of Earth and Planetary Sciences

American Museum of Natural History

All  images on this page:  Dukelabs.com © 2005

 

 

Public Lecture for the New York Mineralogical Club

Wednesday Evening 08 October 2003

American Museum of Natural History

    Dukelabs geologist and Hofstra University Professor Charles Merguerian discussed the geologic control on the scenery of the Hudson Highlands in the vicinity of Bear Mountain at the October meeting of the New York Mineralogical Club.  The talk explained both the bedrock and glacial geology of the region and explained causes for mineral formation.  With the direct help of Mike Hawkins and Erik Rutnik of the New York State Museum, images of minerals from classic localities were be shown.

    Ancient rock of over a billion year vintage decorate the Hudson Highlands in this tract of New England.  The Hudson River course is emphatically controlled by the structural geology with bends in the river conforming to major cross faults.  The erosive effects of glacial ice flow from two major contrasting directions (NW to SE and NE to SW) was superimposed on the prevailing geologic structure, resulting in truly spectacular scenery.  Many brought vegetables in the event Merguerian screwed up.

 All  images on this page:  Dukelabs.com © 2005

June 2003

View from the WSW of Bear Mountain, the Bear Mountain Bridge, and Anthony's Nose at a major NW to NE bend in the Hudson River.  (From Lowe, 1950, Plate 1.)

    The Dukelabs staff has recently investigated the structural geology of the west and east footings of the Bear Mountain Bridge in connection with a new geotechnical engineering project aimed at replacing the aging cables.  Built ahead of schedule in 1923-24, the bridge was a boon to transportation and commerce and at the time providing the easiest way for New Yorkers to cross the Hudson and partake of recreational areas.  Engineers for the new project will evaluate potential strategies for replacement or strengthening of the aging suspension cable network.  In addition to the images here, annotated scanned images from a brochure published by the NYS Bridge Authority entitled "Bear Mountain Bridge - The History" and a Quicktime Virtual Reality tour of the western bridge area will be found by those who click.

Bear Mountain Bridge - southeastward view from Popolopen Creek Bridge (May, 2003).

    The two main suspension cables consist of 7,542 individual galvanized wires 0.192" in diameter and wrapped to a finished cable diameter of 18.25".  The total length of wire used in both cables amounted to 7,377 miles, almost enough to surround the conterminous United States.  The wire-wrapped suspension cables enter the anchorages where they are concreted into Grenville-aged (~1.0-1.3 billion year old) bedrock on both sides of the bridge.  The main suspension cables are disseminated into 37 strands, each consisting of 196 galvanized wires.  The strands are attached to eyebar chains that are fixed to eyebars attached to the the bedrock anchorages.

Geologic map of the west anchorage of the Bear Mountain bridge showing high grade (granulite facies) Grenville Series metasediments (in green) and the Storm King granitoid gneiss (in orange).  (From Lowe, 1950, Plate 5.)

View of Anthony's Nose, east anchorage buildings and main suspension cables.

View of the NE anchorage building and cable strand separation.

View of cable strands and eyebar chains, east anchorage.

Dukelabs Photos (c) May 2003

Enduring great hardship, Merguerian traveled to New Orleans and spoke at the Rapid Excavation and Tunneling Conference in mid-June.  Between visits to Bourbon Street and a local clinic, he presented a coauthored paper (Merguerian and Ozdemir, 2003) on penetration rate studies for the Queens Tunnel.

Robbins Model 235-282 open main beam high-performance TBM with 19" cutters was used to excavate the Queens Tunnel from 1996 to 1999.

April 2003

The Narrows flood – Post-Woodfordian meltwater breach of the Narrows channel, NYC 

In mid-April Merguerian spoke at the 10th Annual meeting of the Long Island Geologists.  Showing tremendous diversity and an unfathomable ability to concoct bizarre conclusions from weak data spanning divergent branches of geology, he spoke on the subject of The Narrows Meltwater Breach and coauthored a paper on Quicktime Virtual Reality.

Sketchmap showing the v-shaped channel of The Narrows.  Note the absence of roughly 200' of stacked glacial till and outwash and truncation by ~160' of Holocene silt.  (From Merguerian 2003, Figure 5.) 

March 2003

The Classic Minerals of New York City

Dukelabs geologist and Hofstra University professor Charles Merguerian spoke at the NY Mineral Club Show on the subject the Minerals of NYC.  Long the focus of thorough geologic investigation and multi-level excavation, over the past 150 years NYC has yielded many spectacular mineral specimens.  These specimens are sought after by collectors because such specimens are rare in crystalline terranes such as found in NYC.  Much of the rock floor of NYC is covered by younger strata.  Luckily, surface and subsurface rock removal as a prelude to construction of buildings and municipal systems have allowed for the preservation of minerals, typically found along faults and in pegmatite veins.  Dr. Merguerian, who has studied the geology of this region throughout his career and still promises one day to get it right, discussed the geological background for NYC mineralization, the formation of minerals from various geological environments, and described the joys of urban mineral collecting.  His talk was highlighted by views of classic and new NYC mineral specimens, some of which come from the NY Mineralogical Club's collection.

See these Dukelabs links:

Classic Minerals of New York City Gallery

Queens Tunnel Mineral Gallery

Queens Tunnel Mineral Localities                 

Geological Fieldguide for New York City and Vicinity   

The Famous "Sewer" Garnet of New York City

April 2002

Brittle Faults of the Queens Tunnel Complex, NYC Water Tunnel #3

Extending his streak of non-compensated appearances, Charles Merguerian spoke at the Ninth Annual Long Island Geologists Conference at Stony Brook on Saturday, 20 April 2002.  His topic was on the brittle faults of the Queens Tunnel.

Superimposed on the granulite facies gneisses of the Queens Tunnel Complex, are a sequence of brittle faults.  Each with its unique character, orientation, and relative age, the youngest episode of brittle faulting trends NW-SE with steep dip and show predominately strike-slip offset.  Correlative with the famous "125th Street fault" of New York City and parallel to many faults in the NYC area, the faults define a set of fractures along which a recent (2001) earthquake has been localized.

View of a brittle fault in the Queens Tunnel.    

Hosted by our long-time friend and colleague, Dr. Gil Hanson, the conference is a mainstay for geologists and students to meet and present the results of their research on the Geology of the New York Metropolitan region.  Click on the link above for past conference publications and the other fine programs organized by the LIG.

March 2002

Rhyodacite Dikes of the Queens Tunnel Complex, NYC Water Tunnel #3

On the road again, Merguerian spoke at the 37th Annual meeting of the NE Section of the Geological Society of America on the subject of  rhyodacite dikes.   He discussed the scientifically startling and unforeseen discovery made during excavation of the Queens Tunnel.   Exposed ~800' beneath Woodside, Queens, a suite of at least five sub-parallel red-colored rhyodacite dikes display pristine igneous textures.

Although the tunnel boring machine (TBM) may have removed dikes no longer visible in the tunnel walls, the exposed dike rocks underlie a minimum of 667' between stations 109+20 and 152+40 and compose 15.4% of the tunnel perimeter rocks within that 4,320' tunnel reach.  They occur as tabular, discordant bodies roughly oriented N53°W and average just under 10' in thickness.

View of discordant contact of glassy rhyodacite dike and Proterozoic Queens Tunnel gneiss exposed in the sidewall of Queens Tunnel.

View of cooling joints orthogonal to dike contact with Queens Tunnel gneiss.

The rhyodacites are highly porphyritic.  Suspended in the red, siliceous groundmass are phenocrysts of hornblende, clinopyroxene, biotite, plagioclase, and subordinate K-feldspar.  The groundmass is enriched in quartz and K-feldspar and dusted with fibrous aggregates of iron oxide - the probable result of quenching and devitrification of initial felsitic volcanic glass. 

    The dikes crosscut folded Proterozoic Y granulite facies rocks of the Queens Tunnel Complex with which they are genetically and temporally unrelated.  The dikes are cut by a generation of steep, NNE-trending brittle faults that are cut by younger, steep NW-trending faults.  The injection of a suite of rhyodacite dikes that are chemically, texturally, and temporally unrelated to their bedrock hosts, mark an anomalous geological formation that adds a new chapter to the evolution of the New York City area.

February 2002

Dukelabs Geologist Charles Merguerian spoke at a meeting of the New York Mineralogical Club on 13 February 2002 (People's Center, Museum of Natural History, 7 PM).  Accompanied by his assistant, Mickey Merguerian, his digital talk was entitled:

If carefully handled, rocks can be sliced so thin that most minerals in them become transparent to visible light.  Viewed under a polarizing (petrographic) microscope, with light penetrating them from beneath, such thin sections reveal the identity and composition of minerals by exhibiting their unique optical properties.  By viewing their textures and spatial relationships, the mineral paragenesis (sequence of formation) can be learned in this way.  Field geology is enhanced tremendously using petrographic techniques to peer into the invisible world of internal mineral relationships.

Igneous Texture:  Interlocking texture in a clinopyroxenite.

His talk on 13 February 2002 was in digital format using the most modern technology available that morning.  He explained the art of thin section preparation from field collecting, to rock chip preparation, to final production of the thin section – basically a rock and glass sandwich (hold the lettuce and mayo – add the epoxy!).  Rock textures unique to the igneous, metamorphic, and sedimentary rock types were examined next as an introduction to the secrets of interpreting geologic history through the magic and natural beauty of the petrographic microscope.

Metamorphic Texture:  Crenulations of early mica foliation.

Fall 2001

Having spent the better part of three years working on the geologic mapping and analysis of the Queens Tunnel, our very own Dr. Merguerian of Hofstra University has coauthored a paper with Drs. Pamela and Patrick Brock from Queens College about the anomalous bedrock formation found in the tunnel.  Based on detailed mapping by CM and joint analysis with the Brocks, they have recognized that the tunnel exposes predominately complexly deformed crystalline rocks of great age, hardness, and high metamorphic grade.  Twice the age of the Hartland bedrock series that was anticipated in the subsurface of western Queens as based on existing maps, surface mapping in adjacent areas, and projections from exposed rock in the vicinity, granulite facies Fordham Gneiss is now recognized in the subsurface of western Queens.

Their joint paper entitled "THE QUEENS TUNNEL COMPLEX - A GRANULITE FACIES ORTHOGNEISS TERRANE EXPOSED IN NYC WATER TUNNEL #3 " was presented by Charles Merguerian at a special theme session at the 2001 Annual Meeting of the Geological Society of America in early November.  Follow the link to the GSA for more details on this and other upcoming events.

Spring 2001

Charles Merguerian and Pamela Chase Brock spoke at the Eighth Annual Long Island Geologists Conference at Stony Brook on Saturday, 21 April 2001.  Hosted by our long-time friend and colleague, Dr. Gil Hanson, the conference is a mainstay for geologists to meet and present the results of their research on the Geology of the New York Metropolitan region.  Click on the link above for past conference publications and the other fine programs organized by the LIG.

Pamela Brock spoke about the petrographic, geochemical, and geochronologic data that have together proven that the rocks of the Queens Tunnel are Grenvillian in age (Brock, Brock, and Merguerian, 2001).  Merguerian spoke about mapping of the raw tunnel excavation exposed by the Queens Tunnel TBM (tunnel boring machine) and an anomalous suite of red-colored volcanic dike rocks ~700’ beneath Woodside, Queens (Merguerian, 2001).  Chemical- and petrographic studies indicate that the rocks are rhyodacitic in composition (chemically between rhyolite and dacite) and exhibit textures and other characteristics typical of shallow-level (hypabyssal) volcanic rocks.  Because they are now found adjacent to the high grade (granulite facies) bedrock series exhumed from depths of roughly 40 km, their presence in a depth position close to where they were initially injected forces a new view of the developmental geology of the NYC region.  Rocks of this composition and structural setting have never before been reported from the New England Appalachians.

Fall 2000

Hofstra University- Distinguished Faculty Lecture Series

Malachite mineralization at trap rock contact, New Britain, CT.

Arsenopyrite crystal from bull quartz vein in schist, Cobalt, CT.

Rare specimen of wire gold from Marble Quarry, Columbia, CA.