The surface heat flow of the Arabian Shield in Jordan

Autor: Andrea Förster, Hans-Jürgen Förster, R. Masarweh, A. Masri, K. Tarawneh, DESERT Group
Přispěvatelé: 2.5 Geodynamic Modelling, 2.0 Physics of the Earth, Departments, GFZ Publication Database, Deutsches GeoForschungsZentrum
Rok vydání: 2007
Předmět:
Zdroj: Journal of Asian Earth Sciences
ISSN: 1367-9120
DOI: 10.1016/j.jseaes.2006.09.002
Popis: Surface heat flow in southern Jordan (western part of the Arabian Plate) was determined in a dense cluster of five, up to 900-m-deep boreholes that have encountered sedimentary rocks of Paleozoic (Ordovician and Silurian) age. These rocks are underlain by an igneous and metamorphic basement, which has been studied for its radiogenic heat production, along the eastern margin of the Dead Sea Transform (DST) fault system. The heat flow, calculated from continuous temperature logs and laboratory-measured thermal conductivity of drillcores and surface samples, averages to 60.3 ± 3.4 mW m −2 and contrasts the common view of the late Proterozoic-consolidated Arabian Shield constituting a low heat-flow province of ⩽45 mW m −2 . Although only characterizing an area of about 300 km 2 , this average is unlikely representing a positive local anomaly caused by voluminous HHP granites/rhyolites at shallow depths. Instead, a heat flow of 60 mW m −2 is considered a robust estimate of the Phanerozoic conductive surface heat flow not only for Jordan, but for the Arabian Shield in areas unaffected by younger reactivation. The large variation in conductive heat flow (36–88 mW m −2 ) previously observed in Jordan, southern Syria, and Saudi Arabia is irreconcilable with their broad similarity in lithosphere structure and composition and rather reflects a combination of factors including low-quality temperature data and insufficient knowledge on thermal rock properties.
Databáze: OpenAIRE