BBakken SubsurfaceNorth Dakota well index

NDIC file 26806 · API 33-061-02776-00-00

TOLLEFSON 41-4H

Operated by MARATHON OIL COMPANY · Mountrail County, North Dakota

Active (A)Oil and gasSpud 2013

Well facts

Operator
MARATHON OIL COMPANY
Status
Active (A)
Well type
Oil and gas (OG)
Field
REUNION BAY
Spud date
Total depth
20,993 ft
Legal location
SESE Sec 33 T152N R93W
Footages
275 ft FSL · 765 ft FEL
County
Mountrail County
NDIC file no.
26806
API no.
33-061-02776-00-00

Location & navigation

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47.93513, -102.58173

Published surface location (NAD83). A horizontal well's lateral can run up to three miles from this point.

See it in 3D

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Production

148 months reported, May 2014 to Aug 2026, BAKKEN pool.

Cumulative oil398KbblMay ’14 to Aug ’26 · 148 of 148 months known
Peak oil rate1,001bbl/dMay 2014 · 29,041 bbl in 29 days
Oil, last 12 months3,004bbl-71% against the 12 before
Gas–oil ratio, last 12 months1,835scf/bblfirst year 1,099 scf/bbl
Water cut, last 12 months43%first year 22% · 140K bbl water in all
Gas sold, last 12 months64%of gas produced · 1,205 mcf reported flared
05001,0001,500Oil bbl/d30201620182020202220242026

Early time

First reported month
May 2014
Months to peak
1 (May 2014)
Peak month rate
1,001 bbl/d on 29 days
First 3 months, oil
66,896 bbl
First 6 months, oil
114,601 bbl
First 12 months, oil
161,870 bbl
First 24 months, oil
214,492 bbl
Share of cumulative in year 1
41%

Today

Last reported month
Aug 2026
Last month with oil
Aug 2026
Latest oil rate
30 bbl/d
Latest rate as share of peak
3.0%
Uptime, last 12 months
33% of days
Cumulative gas
502K mcf
Cumulative water
140K bbl
Pools reported
BAKKEN
Last 12 months as a table
MonthOil bblGas mcfWater bblDaysOil bbl/dGOR scf/bblWater cut
6041,33418322272,20923%
8941,68292729311,88151%
5501,00829021261,83335%
023560——100%
169601616,0000%
0000———
03500———
0000———
0000———
0600———
03210——100%
9401,32582431301,41047%

As first reported to NDIC in each month's report (NDIC Monthly Production Reports, Jan 2003 to Aug 2026). Operators amend past months later and the published reports are not updated, so a month can differ from the current record. A blank or missing month is unknown, not zero, and a cumulative over such months is a lower bound; two pools reported in one month are summed. Rates per producing day divide the month's volume by the days reported, so a month reported without producing days has no rate. Gas–oil ratio is gas produced over oil produced; water cut is water over oil plus water. Months from Jan 2003 to Apr 2015 are read from the Division's PDF reports, which print no flared gas and list a well in a unitized pool only inside its unit's total.

Spacing units

Units whose published footprint holds at least 660 ft of this well's surveyed lateral. Allowances are facts extracted from signed NDIC orders, machine-extracted and not human-reviewed.

Nearby wells

Closest published well heads within 3 miles; wells on one pad share a location.

Other published attributes (1)
symbolA-OG

DMR shapefile columns not shown above, unchanged.