Abbed Babaei

Geochemistry of arc volcanic rocks of the Zagros Crush Zone, Neyriz, Iran

Abstract The northeastern margin of the Tethyan Neyriz ophiolite complex in southwestern Iran is tectonically juxtaposed under cataclastically-deformed island arc volcanic–volcaniclastic rocks. We document this arc component of the Zagros Crush Zone in the Neyriz area, and describe its petrographic and geochemical characteristics. The arc unit which we call the Hassanabad Unit, is tectonically intercalated with Cretaceous limestone in the cataclastic shear zone around the Hassanabad pass north of Neyriz. Analyses of the distributions of the major, rare earth and other trace elements in the volcanic rocks of the Hassanabad Unit reveal a dominantly calc-alkaline island arc composition. Volcanogenic sandstone and sedimentary breccia, with clasts of basalt, andesite and diorite, are cataclastically intercalated with pillowed calc-alkaline island arc volcanic rocks, pelagic limestone and radiolarian chert. Trace element geochemistry corroborates the petrographic evidence that the poorly-sorted and angular volcanogenic sediments were derived locally from the island arc volcanic and intrusive rocks. The emplacement of the volcanic arc rocks adjacent to the thrust sheets of the crustal and mantle sequences of the Neyriz ophiolite was probably a result of subduction-related processes during closure of the Tethys ocean during the Late Cretaceous.

Modeling geological objects with the XML Schema

Interchange, storage, and management of geological data require the development of knowledge-based, standardized vocabularies and data structures. Concepts modeled and designed with the Unified Markup Language (UML), can be mapped into XML Schema Definition Language (XSDL) to compose modular markup languages for each discipline. Developing such efficient, intra-disciplinary, modular and reusable components, based on the XSDL namespace facility and the principles of object-oriented design, reduces redundancy, increases efficiency, scalability, and extensibility, and simplifies the maintenance and future extension of the code. This paper discusses the best practices of composition and reuse of modular intra-disciplinary components by applying XML Schema namespace syntax. In addition to several small examples given for a variety of geological cases, the paper constructs a UML conceptual model and markup language, applying an XML-type library, for a component of the plate tectonics knowledge base (TectonicsML) that deals with the divergent plate boundary.

Developing the earthquake markup language and database with UML and XML schema

Seismic information is commonly shared across networks, and stored in heterogeneous databases that are maintained by different and autonomous groups. Because the metadata of the seismic information is generally not structured, information loss commonly occurs when data is transmitted from one source to another. Minimizing such information loss and enhancing information interchange over the Web require construction of specific markup languages for each part of seismology. The sub-disciplinary data syntax and vocabularies allow construction of corresponding relational databases to store and interchange the structured data. Developing modular data structures and databases for each sub-discipline allows composition of new languages through reuse, and enables future extension of the vocabulary and maintenance of the knowledge base. In this paper, we show how to design the conceptual and logical models for a small set of seismology that deals with earthquake (EarthquakeML). We discuss the application of the UML to the design and mapping of the object model into W3 XML Schema and database. The emphasis is on designing components that can be reused across discipline, and reduce redundancies by developing type libraries. We show how to map the XML schema into a relational data model; and implement the EarthquakeDB with the Microsoft Access DBMS.