# Regional hydrogeology — grounding notes & model anchors

Working notes for the Israel carbonate-mountain / desert-margin modeling program.
Figures below are the anchors baked into `models.py` and the terrain model.

## 1. The Mountain Aquifer (Judea Group) — the master system

- **Rock:** Late Albian–Turonian limestone & dolomite of the **Judea Group**,
  ~800 m thick, strongly **karstified**; karstification raises hydraulic
  conductivity by **several orders of magnitude**, so flow is conduit-dominated
  in the lower sub-aquifer and fracture-dominated in the upper.
- **Structure controls flow:** folding (the Judean anticlinorium) + lithology
  set the flow regime; water moves **westward from the hydrogeologic divide**,
  then turns clockwise at the confined foothills toward two outlets.
- **Yarkon–Taninim basin** (western Judea Group): **largest freshwater source
  in Israel, ~360 MCM/yr.** Combines humid + arid recharge zones, phreatic +
  confined parts, fresh + saline boundaries. → *Model A* (double-reservoir
  recession) and *Model D* (recharge balance to 360 MCM/yr).

## 2. Structural / geomorphic model of the Judean hills

- Broad **anticlinorium**, axis ~NNE–SSW; crest near the Jerusalem watershed.
- **Asymmetric drainage:** long gentle **western dip-slope** wadis → coastal
  plain / Mediterranean; short, steep **eastern** wadis → Dead Sea rift.
- **Differential erosion** of alternating hard **Mizzi** dolomite / soft
  **Meleke** chalk (Bina Fm members) → the terraced hillsides.
- Encoded in `geomorph.make_judean_terrain` as arch + fold-parallel erodibility
  bands + rain-shadow rainfall field + rift base level.

## 3. Desert margin — Judean Desert wadis

- **Rainfall gradient:** ~**250 mm/yr** at headwaters → ~**50 mm/yr** at outlet.
- **Flash-flood dominated:** rapid response to intense, localized storms
  (documented events ~**60 mm depth at >50 mm/h**).
- Standard modeling: rainfall-runoff with **SCS Curve Number**, **Green–Ampt**,
  or **Horton** infiltration; paleoflood hydrology for magnitude/frequency.
  → *Model C* (SCS-CN peak calibration).

## 4. Next regions to extend to (same framework)

- **Mount Carmel:** faulted carbonate block, coastal springs, separate
  hydrogeologic compartment — good test of structural compartmentalization.
- **Galilee:** higher rainfall, basalt cover in the east (Golan/Lower Galilee)
  overprinting the carbonate — a two-lithology recharge contrast.

## Sources
- Yarkon–Taninim basin hydrogeology (case study & critical review): https://www.sciencedirect.com/science/article/abs/pii/0022169494901309
- A highly active karstic aquifer bounded by saline waters: the Judea Group aquifer: https://www.researchgate.net/publication/345445451_A_highly_active_karstic_aquifer_bounded_by_saline_waters_The_Judea_Group_aquifer
- The Yarkon–Taninim Basin — a major carbonate aquifer: https://www.researchgate.net/publication/346855849_The_Yarkon-Taninim_Basin-An_Example_of_a_Major_Carbonate_Aquifers_in_Israel
- Yarkon–Taninim aquifer — what radiocarbon can tell (Cambridge Core): https://www.cambridge.org/core/journals/radiocarbon/article/abs/yarkontaninim-aquifer-judea-group-israel-what-radiocarbon-can-tell/8F52770237081874EFADD1477262DFF8
- Salinity sources, Judea Group aquifer — conceptual hydrogeological model: https://www.sciencedirect.com/science/article/abs/pii/S0022169402002160
- Largest floods in steep bedrock channels, Southern Judean Desert: https://www.sciencedirect.com/science/article/pii/S2214581821001154
- Contrasting rainfall-runoff of floods in desert vs Mediterranean basins (HESS): https://hess.copernicus.org/articles/23/2665/2019/
- Paleoflood hydrology, Nahal Ashalim (Dead Sea): https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2006WR004956
- Bedrock geology & building stones of the Jerusalem area (Bina Fm members): https://www.researchgate.net/publication/335761910_Appendix_1_Bedrock_Geology_and_Building_Stones_in_the_Western_Wall_Plaza_Excavations_and_the_Jerusalem_Area