# Relationship history for MSHA mine 1600995

Current hierarchy: **Wilks Brothers LLC → Carbo Ceramics Inc → NEW IBERIA PLANT**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Kennecott Copper Corp → NEW IBERIA PLANT; 1950-01-01 to 1981-06-03; source msha-controller-operator-history
- **controller_controls_mine:** Kennecott Corp & Dresser Industries → NEW IBERIA PLANT; 1950-01-01 to 1987-06-29; source msha-controller-operator-history
- **operator_operates_mine:** Carborundum Company → NEW IBERIA PLANT; 1980-12-01 to 1981-06-03; source msha-controller-operator-history
- **controller_controls_operator:** Kennecott Copper Corp → Carborundum Company; 1980-12-01 to 1981-06-03; source msha-controller-operator-history
- **operator_operates_mine:** Sohio Electro Minerals Company → NEW IBERIA PLANT; 1981-06-04 to 1986-03-31; source msha-controller-operator-history
- **controller_controls_mine:** British Petroleum Company PLC → NEW IBERIA PLANT; 1981-06-04 to 1986-03-31; source msha-controller-operator-history
- **controller_controls_operator:** British Petroleum Company PLC → Sohio Electro Minerals Company; 1981-06-04 to 1986-03-31; source msha-controller-operator-history
- **operator_operates_mine:** Standard Oil Proppants Company Ltd → NEW IBERIA PLANT; 1986-04-01 to 1987-06-29; source msha-controller-operator-history
- **controller_controls_operator:** Kennecott Corp & Dresser Industries → Standard Oil Proppants Company Ltd; 1986-04-01 to 1987-06-29; source msha-controller-operator-history
- **operator_operates_mine:** Carbo Ceramics Inc → NEW IBERIA PLANT; 1987-06-30 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Gary A  Kolstad et al → NEW IBERIA PLANT; 1987-06-30 to 2020-06-30; source msha-controller-operator-history
- **controller_controls_operator:** Gary A  Kolstad et al → Carbo Ceramics Inc; 1987-06-30 to 2020-06-30; source msha-controller-operator-history
- **controller_controls_mine:** Wilks Brothers LLC → NEW IBERIA PLANT; 2020-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Wilks Brothers LLC → Carbo Ceramics Inc; 2020-07-01 to current/open; source msha-controller-operator-history