Reconciling Reported Well Locations in Historic Records of the Trenton Oil and Gas Field of Indiana

Zuppann, Charles W.; Jacob, David; Willett-Jacob, Ian; Montgrain, Laura; Massa, Corbin; Dintaman, Celeste; Powell, Richard; Keller, Stanley J.

Indiana's Trenton Field and Ohio's Lima Trend together form the nation's second oldest giant petroleum field. Discovered in 1886, the Indiana portion covers about 4,300 square miles and produces oil and gas from Ordovician strata. The field's age, size, and poorly documented history are serious obstacles to evaluating its potential for additional production. Many well locations were either poorly described or even unreported when they were drilled. The Trenton Field was reported in 1916 to contain more than 36,000 wells. However, the Indiana Geological Survey (IGS) Petroleum Database Management System currently has information for only about 24,000 wells, which leaves some 12,000 wells unverified. This study uses more than 3,000 maps of various dates, scales, and extents along with other well records, to better determine old well locations in the Trenton Field.

Most IGS Trenton Field well locations were derived from conflicting and unreconciled maps available in one of six historic map vintages:

1902: maps and drillers' logs from the Ohio Oil Company covering seven densely drilled counties in the northeast part of the field (Adams, Blackford, Delaware, Grant, Huntington, Jay, and Wells Counties), herein called the "seven-county area";

1938: IGS maps that cover the seven-county area;

1962: IGS Preliminary Well Location Maps of the seven-county area;

1982: IGS County Well Location Maps covering the entire field;

1995: IGS maps that unaccountably differ significantly from the 1982 maps;

2004: IGS digital well location maps.

Additional obstacles to resolving the well location issue: 1) Most of the maps were constructed on different geographic base grids and 2) little documentation describing the procedures used to construct maps prior to 1995 is available.

A small pilot study showed that digitizing and comparing the coordinates and symbols for every well on every map layer in the seven-county area is too costly. Instead, we developed procedures in which the source maps are: 1) scanned as raster images; 2) color-coded according to source date, arranged in partially transparent ArcMAP layers, and stacked to allow simultaneous comparison; and 3) georeferenced at every congressional section corner to view well locations on a common base. Viewing the stacked layers together helps determine whether symbols on one layer match those on other layers (based on close proximity of the symbols) or whether they represent unique well locations.

AAPG Search and Discovery Article #90163©2013AAPG 2013 Annual Convention and Exhibition, Pittsburgh, Pennsylvania, May 19-22, 2013