Terroir 2004 banner
IVES 9 IVES Conference Series 9 An overview of geological influences on South African vineyards

An overview of geological influences on South African vineyards


The role of soils and bedrock geology has long been acknowledged as a fundamental component of terroir. In South Africa the influence of geology is misunderstood and some important geological components will be highlighted in this paper.
In South Africa’s Coastal Region the oldest rocks comprise the Late Proterozoic – Cambrian shaley sediments of the Malmesbury Group, and the Cambrian age granitic intrusives of the Cape Granite Suite. Locally these are overlain by sediments of the Klipheuwel Group. These units are unconformably overlain the Middle Ordovician–Early Carboniferous Cape Supergroup, whose basal portion comprises the sandstones of the Table Mountain Group which produce the dramatic mountain scenery of the area.
The Breede River Region covers the valley of the Breede River, to the east of the Coastal Region. The Worcester fault is the major feature defining the geology of this area. To the east of the fault the geology is essentially similar to the Coastal Region. To the west the upper portions of the Cape Supergroup, the Bokkeveld and Witteberg Groups, are present comprising sandstone and shaley sediments. Late Carboniferous–Permian age sediments of the Karoo Supergroup overly the Cape Supergroup and Upper Jurassic-Early Cretaceous sediments of the Uitenhage Group are preserved locally as unconformable remnants.
The following geological features are important for the Coastal Regions vineyards. Soils are often acidic and potassium rich, whilst granites weather to produce both saprolites and kaolin, which are possibly unique in terms of vineyard soils. River gravels are noted in two scenarios, firstly vineyards are planted in river floodplains and secondly fossil gravel terraces exist above the current river level.
In the Breede River Region river gravels are important whilst a significant portion of vineyards are planted on loam soils containing calcareous layers. These calcareous layers are formed as a result of excess evaporation over precipitation in this low rainfall region. A geological control may exist for the formation of these calcareous layers above specific bedrock strata. These soils are unique in the South African context, as they are naturally alkaline.
In addition topography resulting from differential weathering of the geological units is significant in the local terroir. Factors such as warm or cool slope orientation and the effects of altitude on mean temperatures and rainfall are important.


Publication date: January 12, 2022

Issue: Terroir 2004

Type: Article


C. J. Bargmann

Geological Consultant, 5, Allt-y-Wennol, Pontprennau, Cardiff, CF23 8AS, United Kingdom

Contact the author


Terroir, wine, geology, South Africa, Coastal Region, Breede River Region


IVES Conference Series | Terroir 2004


Related articles…

Distribution analysis of myo and scyllo-inositol in natural grape must

s it is well known, myo and scyllo-inositol are two characteristic sugars of grape must and, for this reason, their quantification has been proposed to control the authenticity of the concentrated and rectificated grape must.

Narrow terraces and alternative training systems for steep sloop viticulture – Douro region

In Douro Region, vineyards are usually planted on hillsides with steep sloops. The models currently used for planting those vineyards are, depending on the initial slope of the hillside, vertical planting or terraces.

Dynamics of Saccharomyces cerevisiae population in spontaneous fermentations from Granxa D’Outeiro terroir (DOP Ribeiro, NW Spain)

Granxa D’Outeiro is a recovered ancient vineyard located in the heart of DOP Ribeiro, where traditional white grapevine varieties are growing under sustainable management. Spontaneous fermentations using grape must from Treixadura, Albariño, Lado, Godello, and Loureira varieties were carried out at experimental winery of Evega. Yeasts were isolated from must and at different stages of fermentation. Those colonies belonging to Saccharomyces cerevisiae were characterized at strain level by mDNA-RFLPs.

Rapid damage assessment and grapevine recovery after fire

There is increasing scientific consensus that climate changeis the underlying cause of the prolonged dry and hot conditions that have increased the risk of extreme fire weather in many countries around the world. In December 2019, a bushfire event occurred in the Adelaide Hills, South Australia where 25,000 hectares were burnt and in vineyards and surrounding areas various degrees of scorching and infrastructure damage occurred. The ability to coordinate and plan recovery after a fire event relies on robust and timely data. The current practice for measuring the scale and distribution of fire damage is to walk or drive the vineyard and score individual vines based on visual observation. The process is time consuming, subjective, or semi-quantitative at best. After the December 2019 fires, it took many months to access properties and estimate the area of vineyard damaged. This study compares the rapid assessment and mapping of fire damage using high-resolution satellite imagery with more traditional ground based measures. Satellite imagery tracking vineyard recovery in the season following the bushfire is being correlated to field assessments of vineyard productivity such as canopy health and development, fertility and carbohydrate storage. Canopy health in the seasons following the fires correlated to the severity of the initial fire damage. Severely damaged vines had reduced canopy growth, were infertile or had very low fertility as well as lower carbohydrate levels in buds and canes during dormancy, which reduced productivity in the seasons following the bushfire event. In contrast, vines that received minor damage were able to recover within 1-2 years. Tools that rapidly and affordably capture the extent and severity of damage over large vineyard area will allow producers, government and industry bodies to manage decisions in relation to fire recovery planning, coordination and delivery, improving the efficiency and effectiveness of their response.

Genetic traceability of ‘Nebbiolo’ musts and wines by single nucleotide polymorphism (SNP) genotyping assays

AIM: ‘Nebbiolo’ (Vitis vinifera L.) is one of the most ancient and prestigious Italian grape cultivars. It is renowned for its use in producing monovarietal high-quality red wines, such Barolo and Barbaresco. Wine quality and value can be heavily modified if cultivars other than those allowed are employed.