DATA INCLUDED 
This report includes data for 595 wells com¬ 
pleted on or before January 1, 1970, and updates 
Museum Bulletins 373 and 390. It includes deep 
gas exploratory wells and field wells drilled, ex¬ 
cept those in gas storage fields. Supplements, 
at periodic intervals, will update well data. 
Well records in this report and previously pub¬ 
lished records are available for examination at 
the offices of the Geological Survey in Albany 
and Wellsville. If the well record indicates that 
well cuttings are available, these may be ex¬ 
amined at one of the above offices. Drillers’ logs, 
geologic logs, and electric logs are on file for many 
of the wells, with the exception of a few wells held 
temporarily on a confidential basis at the request 
of the operator. Open file records may be examined 
in Albany and Wellsville. 
Most of the gas field discovery wells, shown 
in Figure 1 (pages 4-5), list the county and town¬ 
ship, year discovered, production formation, 
operator, and amount of gas produced by the 
discovery well. 
The information obtained from drillers’ and 
geological records on gas wells was gathered 
from companies and individuals. These data 
were recorded on index cards and the wells lo¬ 
cated by latitude and longitude on 15-minute 
quadrangles from location plats, township maps. 
Additional information was obtained by field 
visits. This report has been developed by com¬ 
puter printout of well locations on the enclosed 
maps and skeletal logs in Table I. 
EXPLANATION OF MAP PLATES 
The scale of the Eastern and Western maps of 
the New York State map is 1:500,000 (1 inch = 
about 8 miles). A grid pattern of the 15-minute 
quadrangles of the United States Geological Sur¬ 
vey is drawn on the maps. Names of the quad¬ 
rangles appear in the upper left corner, where 
feasible. Detail maps at a scale of 1:125,000 are 
drawn for areas too congested to show at a scale 
of 1:500,000. Wells are identified by permit 
number in the table and on the map plates. Ap¬ 
propriate symbols indicate results and deepest 
formation penetrated for each well. 
Geologic features on the Eastern map (Plate 
1A) include two major areas of Precambrian 
rocks: the southern edge of the Adirondack 
Mountains in northeastern New York, and the 
northern edge of the Hudson Highlands in south¬ 
eastern New York. The boundaries are taken 
from Geologic Map of New York State (1961). 
A few Precambrian inliers are indicated south of 
the Adirondack Mountains and north of the Hud¬ 
son Highlands; a few Paleozoic outliers are shown 
within the southern Adirondacks. 
The Clarendon-Linden structure, a major fea¬ 
ture shown on the western map (Plate 1B) extends 
south from Lake Ontario through southeastern 
Orleans County and bisects Genesee County. 
On the maps, the Oriskany horizon line marks 
either (1) actual Oriskany Sandstone outcrop, 
or (2) the base of the correlative Glenerie Lime¬ 
stone in the Hudson Valley, or (3) the base of the 
Onondaga Limestone where the Oriskany is 
absent. 
The “no sand” area on the map shows where 
Oriskany Sandstone is apparently absent in the 
subsurface, as determined through study of well 
samples, drillers’ logs, and geological logs. This 
absence may be due either to post-Oriskany 
erosion or nondeposition because of a pre-Oriskany 
high. The ends of the inferred Oriskany bound¬ 
aries are dashed, indicating the lack of sufficient 
subsurface data. 
3 
