Geodynamic GPS Measurements in the Dinarides Test Area and Comparison to Recent Geological Tectonic Movements

U području Dinarida, u čijoj građi prevladavaju mezozojske karbonatne stijene, na više mjesta pojavljuju se i znatnije mase paleozojskih stijena, koje su građene od gipsa i anhidrita. U hrvatskom dijelu Dinarskoga gorja takve pojave najzastupljenije su u prostoru Knina, Vrlike, Sinja i Drniša koje je odabrano za test područje. U recentno vrijeme u područjima s kemogenim sedimentima primijećena je veća tektonska aktivnost. Na odabranom test području starije paleozojske stijene nalaze se u dolinama, iako bi se očekivalo da se nalaze na okolnim brdima. Kako bi se detaljnije proučio i empirijski geodetskim metodama doveo u vezu nastanak dolina u reljefu s deformacijama paleozojskih stijena, uspostavljena je geodetska GPS mreža za potrebe određivanja geodinamičkih pomaka na test području. Ovim se radom nastoje prezentirati rezultati dvogodišnjeg istraživanja geodinamičkih pomaka na području od Knina do Sinja. U tri GPS kampanje tijekom dvije godine izvedena su mjerenja na osam geodetskih točaka, koje su stabilizirane u interesnom području tako da se omogući maksimalna točnost mjerenja uz prisilno centriranje GPS antena iznad točaka. Računalna obrada GPS mjerenja izvedena je uz pomoć znanstvenog softvera GAMIT/GLOBK, programskog paketa za analizu GPS mjerenja razvijenog na Massachussetts Institute of Technology (MIT), posebno za određivanje geodinamičkih pomaka, izrađenog u prvom redu za istraživanja deformacija Zemljine kore.In the area of carbonate or karst Dinarides, besides the dominant Mesozoic carbonate rocks, in many places more significant mass of Paleozoic sediments can be found, represented by gypsum and anhydrite. In the Croatian part of the Dinara Mountains such phenomena are most frequent in the area of Knin, Vrlika, Sinj and Drniš which was selected for the test area. Recently, in areas with chemogenic sediments, a larger tectonic activity has been noted. At the selected test area older Paleozoic rocks are located in the valleys, although it is expected to be located on the surrounding hills. For a detailed study and empirical correlation of valley formation in the relief with deformations of Paleozoic rock formations using geodetic methods, a geodetic GPS network for the purpose of determination of geodynamic movements in the test area has been established. The goal of this article is to present the results of a 2-year research of geodynamic shifts in the area between Knin and Sinj. The measurements were carried out through 3 GPS campaigns (every 6 months) on 8 geodetic points, which were stabilized in the area of interest with forced centring of GPS antenna above points, in order to enable maximum measurement accuracy. Computer processing of GPS measurements was made with scientific software GAMIT/GLOBK, the software package for analysis of GPS measurements developed at the Massachusetts Institute of Technology (MIT), particularly for the determination of geodynamic movements, designed primarily for research of the Earth\u27s crust deformation