# Relationship history for MSHA mine 0503029

Current hierarchy: **Occidental Petroleum Corp → Sheridan Enterprises Inc → East Salt Creek Test Site No 1 Mine**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **controller_controls_mine:** Occidental Petroleum Corp → East Salt Creek Test Site No 1 Mine; 1977-02-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Sheridan Enterprises Inc → East Salt Creek Test Site No 1 Mine; 1977-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Occidental Petroleum Corp → Sheridan Enterprises Inc; 1977-03-01 to current/open; source msha-controller-operator-history