Tiago Macheira Subbasin Aquifer Characteristics
The hydrogeology of the Tiago Macheira Subbasin is defined by its specific geological boundaries and the movement of water through its subsurface layers. Understanding the relationship between the terrain and the water table is essential for mapping how groundwater behaves within this region.
Geological Boundaries and Flow Dynamics
To the north, the Tiago Macheira Subbasin meets the Tassajara Formation. A critical characteristic of this boundary is that no groundwater exchange occurs between the subbasin and this formation, effectively isolating the two systems.
The movement of groundwater within the subbasin is primarily driven by the slope of the regional terrain and the surface of the water table. Consequently, the general flow of water moves from the southeast toward the northwest or north.
Aquifer Depth and Classification
Groundwater in the subbasin is categorized into two distinct types based on its depth and containment: uncontained shallow groundwater and deeper confined water.
Uncontained shallow groundwater refers to water located in the upper layers of the soil and rock that is not trapped under pressure. In this subbasin, these waters are found within 25 feet (8 m) of the surface.
Confined water is groundwater trapped beneath a layer of low-permeability rock or clay. These deeper reserves are found at varying depths, typically ranging from 75 feet (20 m) to 150 feet (50 m) below the surface.
Key Facts
- Flow Direction: Southeast toward the northwest or north.
- Northern Boundary: Contacts the Tassajara Formation with zero groundwater exchange.
- Shallow Water Depth: Within 25 feet (8 m) of the surface.
- Confined Water Depth: Between 75 feet (20 m) and 150 feet (50 m).
- Driving Force: Regional terrain slope and water table surface.
| Water Type | Containment Status | Depth Range (Feet) | Depth Range (Meters) |
|---|---|---|---|
| Shallow Groundwater | Uncontained | 0 - 25 ft | 0 - 8 m |
| Deep Groundwater | Confined | 75 - 150 ft | 20 - 50 m |
Frequently Asked Questions
Does water flow between the Tiago Macheira Subbasin and the Tassajara Formation?
No, there is no groundwater exchange between the Tiago Macheira Subbasin and the Tassajara Formation to the north.
In which direction does the groundwater flow?
The groundwater generally flows from the southeast toward the north or northwest, following the slope of the regional terrain.
How deep is the shallow groundwater in this subbasin?
Uncontained shallow groundwater is located within 25 feet (8 m) of the surface.
At what depth is the confined water found?
Confined water levels occur at various depths ranging from 75 feet (20 m) to 150 feet (50 m) below the surface.
What determines the direction of the groundwater flow?
The flow is determined by the water table surface and the slope of the regional terrain.