1. The Wink Sinks Winkler County, Texas Bob Trentham, CEED, UTPB

2. Historic well and field information: What do we know? Wells were drilled to 300 to 900’ where 15 ½” or 12 ½’ casing was set and cemented to protect surface water. Drilled to the top of the Tansill and 8 5/8” cemented with 500 – 600 sacks of cement. Drilled to TD and produced Open Hole or with liner. By 1930, some wells were making as much as 20,000 BW and 50 BO. Earthen, unlined pits were used for storage of oil and water. It was assumed the water would evaporate. In places, however, the water table rose >10’. 3,500 – 9,500 PPM TDS in 1920’s produced water. 99,000 PPM TDS in water “passing through salt section”. In 1956, 350,000 BWPD was still being diverted to disposal pits at about the time when water floods were starting. Many irregularities in subsurface maps are due largely to errors in measurement resulting from crooked holes (Ackers, et.al., 1930, p.934)

3. Southern Crude #T-88-N-3, Sec 28, Blk 26, Showing 40 0 dip on beds at 2350’. The hole was 32 0 off vertical. Ackers, et.al, 1930

4. Southern Crude #T-88-P-1 Hendrick showing collapse in the “anhydrite section”. In 1928. This had to be present PRIOR to any oil and gas activity in the area.

5. 2005 Apache #10 has lost circulation and washout at~1800’ in Salado Apache #12 well has 16’ bit drop and loses circulation. Begins to flow 100 BO per hour. Apache, 2005 Flowing from 1800’ in Salado Salt Gulf, 1982 Flowed 23,000 BO from ??? Arrington, 1997 Flowed 10,000 BO from ??? Still flowing Wink Sink 1 1980 Wink Sink 2 2002 Wink Sag 1980 - 2002

6. Apache new drills

7. 1980 “The” Wink Sink forms The base map is from the 1930 publication on the Hendrick Field, Ackers et.al., AAPG, vol 14, p.923-244. Contoured on top of Tansill. Wink Sink 1 1980

8. 1982 Gulf #28 Hendrick, originally drilled in 1928, flowed 23,000 BO in 20 days… Capitan Reef? Gulf, 1982 Flowed 23,000 BO from ??? Wink Sink 1 1980

9. 1980’s -2002 Wink Sag Anticipated location of next sink. Gulf, 1982 Flowed 23,000 BO from ??? Wink Sink 1 1980 Wink Sag 1980 - 2002

10. 1997 Arrington #2 Hendrick drilled in 1928, flowed 10,000 BO in 30 days still flowing on choke. Gulf, 1982 Flowed 23,000 BO from ??? Arrington, 1997 Flowed 10,000 BO from ??? Still flowing Wink Sink 1 1980 Wink Sag 1980 - 2002

11. 2002 Wink Sink 2 Gulf, 1982 Flowed 23,000 BO from ??? Arrington, 1997 Flowed 10,000 BO from ??? Still flowing Wink Sink 1 1980 Wink Sink 2 2002 Wink Sag 1980 - 2002

12. 2005 Apache #10 has lost circulation and washout at~1800’ in Salado Apache #12 well has 16’ bit drop and loses circulation. Begins to flow 100 BO per hour. Apache, 2005 Flowing from 1800’ in Salado Salt Gulf, 1982 Flowed 23,000 BO from ??? Arrington, 1997 Flowed 10,000 BO from ??? Still flowing Wink Sink 1 1980 Wink Sink 2 2002 Wink Sag 1980 - 2002

13. 2005 Apache #10 has lost circulation and washout at~1800’ in Salado Apache #12 well has 16’ bit drop and loses circulation. Begins to flow 100 BO per hour. Apache, 2005 Flowing from 1800’ in Salado Salt Gulf, 1982 Flowed 23,000 BO from ??? Arrington, 1997 Flowed 10,000 BO from ??? Still flowing Wink Sink 1 1980 Wink Sink 2 2002 Wink Sag 1980 - 2002 2006 Apache “loses” well to sheared casing

14. WINK SINK I

15. Measurement of the “ring fractures” around Wink Sink 1 suggests the sink and the sag to the east should be view as a couplet. The feature in the bar ditch of SH115 is not part of the previously existing sets of fractures.

17. Hypotheses on Sink development There are many possible causes of a cavity which eventually results in a collapse: –Fresh waters from shallow aquifers enter borehole and cause dissolution in Salado Salt –Existing Cenozoic collapse in Salado is enlarged by water(s) and collapses –Brine water from surface pits enters along fractures in shallow horizons causing dissolution –Water moving up from Capitan Reef causes dissolution –Water lost through casing into Salado causes dissolution

18. Arco 3D East west lines indicate “disrupted” reflectors in the evaporite section. The top of the Yates (Black line) is at approximately 500ms.

19. Although the location of the Cenozoic Alluvium “Fill Zone” is know as an area of poor quality seismic data for deeper horizons, There maybe shallow data present that would be extremely useful to this study

20. WINK SINK II

21. The water supply wells for the city of Wink are in close proximity to Wink Sink 2 (Gray area), and Sag Area (Blue area) both inside the fenced area. Monitor wells, placed between the Sink and the town are strongly recommended.

22. Wink Sink 2

23. Wink Sink 2 looking south

24. Sag Area to east of Wink Sink 2

25. 6” Gas Pipeline serving Wink has been exposed for over 2 years. The depth of the fracture is >13’. The trend of the this crack and the one through the electric substation is independent of Wink Sink II.