# Relationship history for MSHA mine 4003159

Current hierarchy: **Martin Marietta Materials Inc → Martin Marietta Materials, Inc. → Chattanooga Quarry**

- 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:** Martin Marietta Materials Inc → Chattanooga Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** AMT Florida Rock Industries → Chattanooga Quarry; 2000-04-01 to 2008-04-11; source msha-controller-operator-history
- **controller_controls_mine:** Wright James Et Al → Chattanooga Quarry; 2000-04-01 to 2001-09-22; source msha-controller-operator-history
- **controller_controls_operator:** Wright James Et Al → AMT Florida Rock Industries; 2000-04-01 to 2001-09-22; source msha-controller-operator-history
- **controller_controls_mine:** Florida Rock Industries Inc → Chattanooga Quarry; 2001-09-23 to 2007-11-15; source msha-controller-operator-history
- **controller_controls_operator:** Florida Rock Industries Inc → AMT Florida Rock Industries; 2001-09-23 to 2007-11-15; source msha-controller-operator-history
- **controller_controls_mine:** Vulcan Materials Company → Chattanooga Quarry; 2007-11-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Vulcan Materials Company → AMT Florida Rock Industries; 2007-11-16 to 2008-04-11; source msha-controller-operator-history
- **operator_operates_mine:** Martin Marietta Materials, Inc. → Chattanooga Quarry; 2008-04-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Martin Marietta Materials Inc → Martin Marietta Materials, Inc.; 2008-04-12 to current/open; source msha-controller-operator-history