ALBERT

Description: Since 1963, the International Heat Flow Commission has been fostering the compilation of the Global Heat Flow Database to provide reliable heat-flow data. Over time, techniques and methodologies evolved, calling for a reorganization of the database structure and for a reassessment of stored heat-flow data. Here, we provide the results of a collaborative, community-driven approach to set-up a new, quality-approved global heat-flow database. We present background information on how heat-flow is determined and how this important thermal parameter could be systematically evaluated. The latter requires appropriate documentation of metadata to allow the application of a consistent evaluation scheme. The knowledge of basic data (name and coordinates of the site, depth range of temperature measurements, etc.), details on temperature and thermal-conductivity data and possible perturbing effects need to be given. The proposed heat-flow quality evaluation scheme can discriminate between different quality aspects affecting heat flow: numerical uncertainties, methodological uncertainties, and environmental effects. The resulting quality codes allow the evaluation of every stored heat-flow data entry. If mandatory basic data are missing, the entry is marked accordingly. In cases where more than one heat-flow determination is presented for one specific site, and all of them are considered for the site, the poorest evaluation score is inherited to the site level. The required data and the proposed scheme are presented in this paper. Due to the requirements of the newly developed evaluation scheme, the database structure as presented in 2021 has been updated and is available in the appendix of this paper. The new quality scheme will allow a comprehensible evaluation of the stored heat-flow data for the first time.

Description: Since its establishment in 1963, the International Heat Flow Commission (IHFC) has fostering and curating the Global Heat Flow Database (GHFDB). The dynamic nature of techniques and methodologies used in heat-flow density determination has necessitated regular updates to the database. Despite its widespread utility, the GHFDB faces challenges arising from variations in measurement techniques and data quality. Ongoing efforts are dedicated to overcoming these challenges, aiming to elevate the database's accuracy and reliability, thus solidifying its value within the scientific community. Multiple iterations of the GHFDB exist, primarily focused on characterizing the quality of individual heat-flow data points. However, the establishment of a new, authenticated GHFDB demanded the development of a fresh reporting standards for heat-flow data submitted to the IHFC. This new framework, derived from a collaborative global initiative, incorporates 62 metadata fields. This comprehensive approach became imperative due to the escalating volume of data and the diverse methodologies employed, necessitating a standardized scheme to evaluate the quality of heat-flow density determinations consistently. This update provides insights into the community-driven initiative initiated in 2021, targeting the reassessment of approximately 1,414 publications containing 73,033 global heat-flow data points. A noteworthy aspect of this initiative is the introduction of a novel quality scheme, unifying three independent criteria into a combined score. This score encompasses quantified uncertainty, methodological quality, and the status of overruling effects. The integration of these criteria facilitates a swift comparison of heat-flow data, instantly revealing any missing data or inadequately documented information. The introduction of this quality scheme empowers users to efficiently select reliable heat-flow values tailored to their specific research purposes.

Description: Terrestrial heat-flow determinations are crucial for understanding the thermal structure of the lithosphere. This study presents the results of a revision of the heat flow database in Türkiye contributing to the Global Heat Flow Data Assessment Project conducted by the International Heat Flow Commission (IHFC). The database includes 750 heat flow determinations reported in Türkiye between 1991 and 2023, and are reassessed according to the new IHFC specific structure documented by Fuchs et al. (2023). The data are gathered from the original literature and examined to ensure complete documentation of relevant metadata. The quality score is assigned based on the uncertainty, methodology and environmental disturbances. The new national wide database shows that heat-flow determinations are predominantly distributed in the western part of the country. However, the eastern part of the country has been poorly investigated to date. Despite numerous exploration-based studies conducted in the region concerning its substantial geothermal potential, a noteworthy portion of thermal data remains archived and is not accessible. The study reveals a significant demand for additional heat flow determinations to allow the drawing of a substantially revised and robust heat-flow map. However, the ongoing update of the Türkiye Heat Flow Database already allows a more transparent identification of areas with thermal anomalies.

Description: Recently, the International Heat Flow Commission (IHFC), the Task Force VIII of the International Lithosphere Program (ILP) and a global network of geoscientists have jointly developed new standards for the structure and the quality evaluation of heat flow-density data. Heat-flow data are important for understanding the temperature field at shallow depths to the lithospheric scale and thus are fundamental for geodynamic and tectonic processes as well as for geoenergy applications, like geothermal utilizations. It often builds an essential parameter for analytical or numerical models of subsurface thermal models. Since 2021, the Global Heat Flow Database is undergoing an intensive collaborative assessment considering the new defined standards. The new quality scheme, for the first time, will allow a joint classification of data in terms of (i) numerical uncertainty, (ii) methodological evaluation, and (iii) overriding or perturbing effects. On the example of the Global Heat Flow Database Release 2024, we present for a regional example how the assessment changes the data density and detail of information stored and how the new quality standards effect regional heat flow statistics.