Black Sea Crustal Structure and Crustal Type from Integrated Quantitative Analysis of Deep Seismic and Gravity Anomaly Data

Abstract

The composition and thickness of crustal basement are critical to frontier hydrocarbon exploration in deep-water rifted continental margin settings. For the Black Sea, we need to know the distribution of continental and oceanic crust, ocean-continent transition structure, continent-ocean boundary location and magmatic type (whether magma poor, normal or magma rich).

We apply a set a quantitative analytical techniques based on ION's deep long-offset seismic reflection data. These quantitative analytical techniques consist of:

The combined interpretation of these independent quantitative measurements are used together to determine OCT structure, COB location, the distribution of oceanic crust and hyper-extended lithosphere.

Superposition of the 3D Moho surface determined from gravity inversion onto PSDM and PSTM seismic sections provides assistance to, and validation of, deep seismic reflection interpretation. Integrated quantitative analysis maximises the use of the ION deep seismic data.

Radiogenic heat-productivity within continental basement contributes significantly to hydrocarbon maturation; in contrast oceanic crust or exhumed mantle contributes very little. Continental lithosphere thinning and residual thicknesses of continental crust determined from gravity inversion have been used to predict the preservation of continental crustal radiogenic heat productivity and the transient lithosphere heat-flow contribution within thermally equilibrating lithosphere. These are used are used to produce regional grids and maps of top-basement heat-flow history. Outputs from our 3D quantitative analysis of the Black Sea include grids of lithosphere thinning, ß factor and heat flow history for input to petroleum systems modelling.

AAPG Datapages/Search and Discovery Article #90226 © 2015 European Regional Conference and Exhibition, Lisbon, Portugal, May 18-19, 2015