A5: KIMBERLITES IN THE CAYUGA LAKE REGION OF CENTRAL NEW YORK: THE SIX MILE CREEK, WILLIAMS BROOK, AND TAUGHANNOCK CREEK DIKES
David Bailey
Department of Geosciences
Hamilton College
Clinton, NY 13323
dbailey@hamilton.edu
Marian Lupulescu
New York State Geological Survey
Albany NY
mlupules@mail.nysed.gov
INTRODUCTION
Diamonds in New York State? While it may be hard to believe, just over 100 years ago local residents and scientists thought that there was a very strong possibility of finding diamonds in upstate New York (Figure 1) . This diamond rush lasted for the first few decades of the 20th century, but after numerous failed attempts, the diamond hunt was over and this interesting episode in New York State’s history was largely forgotten.
Below we provide a chronological outline of the scientific discoveries and reports on the kimberlitic rocks of central New York, followed by detailed descriptions of the three dikes that will be visited on today’s field trip. For a more detailed discussion of the ages and origins of these unusual rocks, the reader is referred to Kay et al. (1983) and Bailey & Lupulescu (2015).

A5: KIMBERLITES IN THE CAYUGA LAKE REGION OF CENTRAL NEW YORK: THE SIX MILE CREEK, WILLIAMS BROOK, AND TAUGHANNOCK CREEK DIKES

Meeting Place in Wegman's Parking Lot

Sixmile Creek Dike
Parking lot for Mulholland Wildflower Preserve, south off of Giles Street, on east side of Six Mile Creek.
Follow the nature trail on the east side of Six Mile Creek for ~600 m (~ 1/3 mile); two dikes will be exposed and clearly visible in the streambed. The largest is ~ 20 cm-wide, and stands out prominently from the surrounding shales. The second is a cluster of small, anastomosing dikelets ranging from 1 to 8 cm in width. These are two of the seven dikes that have been observed in a 4 km long stretch of the Six Mile Creek drainage southeast of Ithaca (Figure 6).

STOP 2. WILLIAMS BROOK DIKE
Small gravel turn out on west side of NY Route 96 just after turn for Hopkins Place.
Just to the north of the turn out, Route 96 crosses over a small creek. Enter the creek on the west side of the road, and hike upstream for ~ 60 m. The Williams Brook kimberlite is a dark green-black dike approximately 3.5 m wide; it is best exposed on the northern bank of the creek.

STOP 3. TAUGHANNOCK CREEK DIKES
Parking Location and Coordinates: Small gravel turn out on south side of Taughannock Park Rd.
Take the short fishing access path to the nicely exposed rocks on the banks of Taughannock Creek. A total of 15 individual dikes, in five clusters, have been reported from a 1.5 km long section of Taughannock Creek (Figure 15) (Foster, 1970; Martens, 1924; Matson, 1905). Due to erosion and revegetation along the banks of the creek, few of these dikes are currently exposed. We will try to find two of the westernmost dikes in Taughannock Creek. NOTE: All of the dikes are within the confines of Taughannock Creek State Park, and sample collecting is prohibited.