Cave and Karst

  Aragonite Vs Calcite Cave Speleothem Buchanan (2025)   Aragonite and calcite are both polymorphs of calcium carbonate (CaCO ₃ ), meaning they have the same chemical composition but different crystal structures. Aragonite is commonly found in marine shells, coral skeletons, and cave formations, while calcite is more widespread in sedimentary rocks like limestone, dolomite. In caves, aragonite and calcite both play significant roles in speleothem (cave formation) development, they form under different conditions and exhibit distinct crystal habits. Picture: - Aragonite sprays- Wolkburg Caves, Limpopo, South Africa, Lake chamber (Mike Buchanan) Crystallography of Aragonite ·          Crystal System: Orthorhombic ·          Habit: Prismatic, needle-like, or columnar crystals, often forming fibrous or radiating aggregates ·          Cleavage: D...

  Environmental Impact Report: Acid Mine Drainage, Groundwater Contamination, and Radon Emissions in the Cradle of Humankind Mike Buchanan 2023   Executive Summary This report investigates the significant environmental challenges arising from acid mine drainage (AMD), groundwater contamination, and the emission of radon gas (Rn-222) in the Cradle of Humankind, a UNESCO World Heritage Site. These issues, primarily stemming from abandoned and relic mines in the Gauteng and Northwest Provinces, pose serious risks to public health, ecological integrity, and cultural heritage. The report outlines the geohydrological mechanisms driving contamination and proposes a multi-tiered remediation strategy supported by recent scientific and governmental findings (Naicker et al., 2003; Coetzee et al., 2006; WHO, 2021). 1. Introduction The Cradle of Humankind, a UNESCO World Heritage Site located in Gauteng, faces pressing environmental issues due to ongoing acid mine drainage (AMD...

  The Importance of Carbonates: A Long‑Overdue Anthropogenic Failure in Global Understanding Mike Buchanan – 2025 Carbonate terrains remind us that the foundations of life, culture and civilisation are often shaped not by the dramatic upheavals we readily perceive, but by the quiet, persistent forces that work in darkness and deep time. In the hidden chambers of karst systems, where water, stone, biology and gravity negotiate their ancient dialogue, we see that the world is built through patient transformation, subtle interaction and the continual re-carving of possibility. These landscapes are a testament to the truth that resilience and vulnerability coexist. They nourish societies with water, fertility and passage, yet remain fragile to human disregard. To understand carbonates is to recognise that our existence is intertwined with processes far older and more intricate than ourselves. That wisdom lies in honouring the slow, delicate architectures that have sustained life lo...