UNEARTHING NEW JERSEY NEW JERSEY GEOLOGICAL SURVEY Vol. 2, No. 1 Winter 2006 Department of Environmental Protection MESSAGE FROM THE STATE GEOLOGIST As New Jersey welcomes Governor Jon Corzine and the Department of Environmental Protection greets Commissioner Lisa Jackson, the Geological Survey is pursuing several new initiatives. This issue of Unearthing New Jersey, focuses on tools and research undertaken by the Survey to provide a better understanding of the near-surface environment and the geology of the State. Ron Witte and Don Monteverde present recent mapping work in the Delaware Water Gap National Recreation Area. Newly mapped karst landscape features including sinkholes, sinking streams, springs and caves were identified along Wallpack Ridge. In the New Jersey Valley and Ridge and Highlands Physiographic Provinces much of the potable water comes from karst terrain. These areas support ecologically sensitive resources that are easily impacted by human activity. Karst areas are also prone to ground subsidence due to the formation of sinkholes. Laura Nicholson is working on the carbonate rock aquifers in northern New Jersey that supply approximately 8 billion gallons of water annually. Unfortunately these aquifers are vulnerable to Bedding surface of the Onondaga Limestone exposed along a small stream contamination from near pollution moving down through fractures in on Wallpack Ridge. The irregularly shaped depressions formed by dissolu- the rock. To better understand these pathways, the Survey recently tion of soluble nodular limestone. The large joints cutting across and paral- conducted studies on the fractured carbonate rocks in Hamburg leling the stream go deep into the rock. Sinkholes in the park tend to follow the same joint trends. Photo by R.W. Witte Borough, Sussex County The research involved characterization of the hydrogeology of the site and two 72-hour aquifer tests to KARST IN THE DELAWARE WATER GAP investigate specific water-bearing zones. Results suggest that under natural flow conditions a varying degree of hydrologic NATIONAL RECREATION AREA connection exists between the shallow and deep aquifers. Greg Herman details new tools and methods used to develop By Ron W. Witte and Donald H. Monteverde the relationship between geology and ground water flow in a computerized hydrogeological framework. Specifically, the heat- pulse flow meter and optical televiewer are teamed with traditional INTRODUCTION borehole geophysics and geographic information systems to Recent mapping in northwestern New Jersey detected a analyze fractured bedrock geology and ground water flow at the large number of karst features found along Wallpack Ridge Heron Run Golf course in Hunterdon County. Combining this in the Delaware Water Gap National Recreation Area (fig. information into a hydrogeologic framework facilitates the modeling 1). Dozens of small sinkholes, sinking streams, springs of the way that water in the aquifer moves and is stored. John Dooley and Larry Müller provide information on the and small caves were identified. The greatest number of mineral prehnite which once was considered for designation as features were found in the Onondaga Formation, a 270 the state mineral of New Jersey. Prehnite is a green, translucent, foot-thick limestone that outcrops on the northwest-facing hydrous, calcium aluminum silicate. It can be mistaken for jade and slope of Wallpack Ridge. Less commonly, karst features is occasionally used as an ornamental stone. It mainly occurs as a also developed in older limestones along the eastern face of vein or filled vesicle in igneous rocks such as basalt. New Jersey Wallpack Ridge. has produced some of the finest specimens from localities near Paterson, Passaic County. A karst landscape typically results when carbonate rock The Survey welcomes your feedback (http://www.njgeology. is dissolved by rain and groundwater. It is characterized org/comments.html). Other recent geologic activities and digital by rocky ground, caves, sinkholes, and subterranean and publications of the Survey are noted elsewhere on the Survey’s discontinuous surface streams. Karst is common in Kittatinny Web site. Printed maps and reports are available to the public Valley and parts of the New Jersey Highlands where thick through the DEP Maps and Publications Office (609) 777-1038, belts of carbonate bedrock underlie lowlands. It was not PO Box 438, Trenton, N.J. 08625-0438 and a publications price list is maintained on the Web. Unpublished information is provided previously recognized in the Delaware Water Gap National at cost by writing the State Geologist’s Office, N.J. Geological Recreation Area (DEWA). However, during the last century Survey, PO Box 427, Trenton, N.J. 08625-0427. Staff are available small caves were discovered outside the park in the same to answer your questions 8 a.m. - 5 p.m. Monday through Friday by limestone-rich formations found in DEWA. calling (609) 292-1185. Karst is a valuable natural resource in New Jersey. In the Valley and Ridge and part of the New Jersey Highlands Karl W. Muessig, New Jersey State Geologist physiographic provinces about 40 percent of potable water comes from karst terrain. NEW YORK Area of NEW JERSEY Also, caves sometimes Detail Sussex contain information about Passaic er Bergen iv past climate, plants and R Warren Morris re Essex a animals, and human Hudson w la Union e history. Karst areas are Hunterdon D Somerset also susceptible to the Middlesex impact of human activity Mercer Monmouth and can be used to monitor environmental health. In addition to its value as a Burlington Ocean natural resource, karst Gloucester Camden Salem areas are prone to ground Atlantic subsidence due to the Cumberland formation of sinkholes. Cape May The Congress recog- nized the value of karst and PENNSYLVANIA NEW JERSEY NEW JERSEY passed two acts to ensure Wallpack Bend its protection on federal lands. The Federal Cave EXPLANATION r Resources Protection e Sussex County New Jersey part of DEWA iv 1) secures, R Warren County Act of 1988 e ar Pennsylvania part of DEWA w protects, and preserves la De Worthington State Forest, significant caves on New Jersey federal lands for the Karst study area perpetual use, enjoyment, 0 5 and benefit of all people, miles and 2) fosters increased cooperation and exchange of information between Figure 1. Location of Delaware Water Gap National Recreation Area (DEWA) in New Jersey and Pennsylvania, and governmental authorities karst study area. and those that utilize caves located on Federal lands for scientific, education, among the New Jersey Geological Survey, U.S. Geological or Recreation purposes. The National Cave and Karst Survey, and National Park Service (NPS) to study and protect Research Act of 1988 1) furthers the science of speleology karst in the Delaware Water Gap National Recreation Area. (caving), 2) centralizes and standardizes speleological Geologic research on federal lands is allowed only after information, 3) fosters interdisciplinary cooperation in cave a permit is issued by the NPS. Unauthorized collecting, and karst research programs, 4) promotes public education, exploring, and mapping of natural and cultural resources are 5) promotes national and international cooperation in strictly prohibited and punishable by fines and imprisonment. protecting the environment for the benefit of cave and karst Inflicting damage to park resources is similarly punishable. landforms, and 6) promotes and develop environmentally To further protect DEWA’s karst resources, the location of sound and sustainable resource management practices. features discussed in and photographed for this article are This act led to the founding of the National Cave and Karst shown at a regional scale. Research Institute (NCKRI) which operates under the auspices of the National Park Service (NPS). PHYSIOGRAPHY AND BEDROCK GEOLOGY These two acts provided the basis for a cooperative effort Long, narrow, and slightly sinuous, Wallpack Ridge extends 25 miles from Wallpack Bend on the Delaware River to Tristates in New York State (fig. 2). Its width varies NJGS between 0.67 and 1.7 miles and its highest elevation is 928 1835 feet. Topography is knobby, typically consisting of short, rocky northeast-trending ridges and benches. Wallpack STATE OF NEW JERSEY Ridge may be divided into three sections (southern, middle Jon S. Corzine, Governor and northern) based on the ridge’s topographic trend. The Department of Environmental Protection southern and northern sections trend about 055 degrees Lisa P. Jackson, Commissioner while the middle trends about 026 degrees. The middle New Jersey Geological Survey Karl Muessig, State Geologist is also the widest section because its rock formations are 29 Arctic Parkway Telephone: (609) 292-1185 inclined much less steeply than those in the lower and P.O. Box 427 FAX: (609) 633-1004 upper parts. On either side of Wallpack Ridge lie Minisink Trenton, NJ 08625 www.njgeology.org (west) and Wallpack (east) Valleys. Both valleys are narrow, Unearthing New Jersey Vol. No. 1 Port Jervis deep, and trend southwest following belts PENNSYLVANIA r Tristates v e Sussex i NEW YORK of weaker rock. The valleys were also the Area of w a r e R County a NEW JERSEY Detail l former sites of a planned hydroelectric and e D water storage project by the Army Corps NorthernRidge Wallpack of Engineers. A dam constructed at Tocks Warren Montague County Island would have flooded Minisink Valley upstream to Port Jervis, New York, and Wallpack Valley upstream to Layton. The reservoir would have provided storage capacity of nearly 250 billion gallons. After Beemerville years of controversy, Congress deauthorized M i n i s i nMiddle k V a Wallpackl l e y Ridge Dingmans the project in 1992. Kittatinny Mountain (fig. Ferry Layton 2) is a prominent ridge that forms the eastern W a l l p a c k V a l l e y NEW JERSEY border of the study area. It separates Minisink Valley from Kittatinny Valley, and runs from the Shawangunk Mountains in New York southwestward through New Jersey into Pennsylvania.