# Geological Influences on Wine Quality: Analyzing Nebbiolo Grapes from Northern Italy
## 1 Introduction  
Wine has been a quintessential product of Europe for thousands of years, particularly in the Mediterranean basin. Today, the foremost global wine producers are Italy, France, and Spain, with Italy distinguished by its vast array of indigenous grape varieties. This diversity sets Italian wines apart from those produced elsewhere, highlighting the intricate relationship between grape cultivation and regional characteristics. The quality of wine is closely linked to the quality of the grapes; optimal conditions for cultivation--healthy wines at the right level of ripeness--are essential for producing high-quality wines [1]. Consequently, exceptional wines are born in the vineyard rather than the cellar. The characteristics of wine are profoundly influenced by grape variety and the vineyard's environmental conditions, particularly the soil's composition, which plays a crucial role in determining the final product's quality [2, 3]. The qualitative and quantitative composition of the inorganic matrix of wine can accurately trace its vineyard of origin, as this is inherently linked to the soil in which the vines grow, the nutrient drainage, and the geological and geochemical properties of the vineyard substrate. Research has shown that specific soil characteristics, such as texture and mineral content, directly impact vine physiology and grape composition, ultimately influencing wine quality [4, 5, 6]. In this context, determining the concentrations of specific trace elements in grapes destined for wine production is essential. Mineral substances, cations, and anions of geological origin are absorbed through the plant's roots and incorporated into the biological tissues of the grape. The concentration of these substances, particularly the cationic fraction, often exists in parts per billion (ppb). Notable elements such as Al, Ba, Mn, Mo, Rb, Si, Sr, and Ti are particularly relevant, as their concentrations reflect the mineral contributions of the soil and the grape clusters' capacity to absorb these metals [7]. Advanced instrumentation allows for the detection of these trace elements, with their relative distribution strongly correlated with the mineralogical composition of the soils, as evidenced, for example, by [PERSON] et al. [8], which reported the straight correlation between isotopic Sr and Pb composition in soils and wines. The Italian peninsula, with its complex tectonic evolution, offers a favorable environment for such studies, resulting in an extremely diverse geological and lithological landscape [7,9]. For premium wines, certification of authenticity and geographical provenance is critical for enhancing market value. Scientific methods can support the artistry of winemaking by establishing a chemical, organic, and geochemical fingerprint for the wine, facilitating effective traceability [7]. Quantifying the inorganic matrix of wine enables precise identification of its vineyard of origin, closely linked to the land's geological and geochemical characteristics [2]. This study analyzes nearly fifty samples of Nebbiolo grapes, musts, and wines sourced from various regions in Northern Italy--specifically Langhe and Canavese (Piedmont), Valtellina (Lombardy), and the small area at the beginning of the Aosta Valley. Nebbiolo is renowned as one of Italy's finest grape varieties, producing esteemed red wines such as Barolo and Barbaresco, known for their depth and aging potential [10,11]. This grape also holds significant cultural and economic importance in Piedmont, a region recognized for its high-quality agricultural production, particularly in the wine sector, which boasts 14 DOCG and 46 DOC designations, many derived from indigenous grapes [10]. Characterized by its late ripening and susceptibility to climatic variability, Nebbiolo flourishes in specific terroirs that enhance its distinctive attributes [12].