# Relationship history for MSHA mine 2901062

Current hierarchy: **Donald R  Shannon → Caprock Sand & Gravel Inc → CAPROCK PIT**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Caprock Sand & Gravel → CAPROCK PIT; 1950-01-01 to 1990-06-30; source msha-controller-operator-history
- **controller_controls_mine:** B J  Woolley → CAPROCK PIT; 1950-01-01 to 1990-06-30; source msha-controller-operator-history
- **controller_controls_operator:** B J  Woolley → Caprock Sand & Gravel; 1950-01-01 to 1990-06-30; source msha-controller-operator-history
- **operator_operates_mine:** Caprock Sand & Gravel Inc → CAPROCK PIT; 1990-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Donald R  Shannon  et al → CAPROCK PIT; 1990-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Donald R  Shannon  et al → Caprock Sand & Gravel Inc; 1990-07-01 to current/open; source msha-controller-operator-history