Lawrence A. Lawver

Present-day Plate Boundary Digital Data Compilation

The PLATES Project compiled digital data representing the present-day plate boundaries. This report includes the digital data in three formats: GMT, KMZ and ArcGIS shapefiles.

Heat flow measurements in the southern portion of the Gulf of California

Abstract Twenty-five new heat flow measurements made in the Gulf of California are presented. All the values except two at the mouth of the Gulf and two in the Sal si Puedes basin are high. The values ranged from 2.0 to greater than 10 μcal/cm 2 sec (82 to > 420 mW/m 2 ) with eight values greater than 5.2 (210 mW/m 2 ). Due to high rates of sedimentation throughout the Gulf, the actual heat flow, in many cases, may be up to 25% greater than that recorded. Most of the heat flow stations are concentrated in the Farallon and Guaymas basins and show a marked increase towards the central deeps, where new crust is believed to be forming. The heat flow values in the Farallon basin show a sharp peak 10–15 km southeast of the central depression while those in the Guaymas basin peak in the depression. The heat flow profiles across the Guaymas and Farallon basins are remarkably similar to those observed on other well sedimented spreading centers such as the northern portion of the Explorer trough. Thus they may provide evidence that the crust is being created by an axially symmetric intrusion process with a major loss of heat due to hydrothermal circulation. The absence of magnetic anomalies in the Gulf has been attributed to the supposed presence of large grains in the intruded basalt. Large grains form by the slow cooling of the basalt under a layer of sediment. Prominent magnetic anomalies have been observed on the northern portion of the Explorer trough. Observational data suggest that the thermal processes at this ridge axis and the center of the Farallon basin are identical. We suggest that further careful study is needed in the Gulf before the slow cooling model is accepted as an explanation for the attenuation of the magnetic anomalies.

Antarctica: Gravity Anomaly and Infrared Satellite Image 1992.

This composite satellite image of the Antarctic continent and surrounding ocean basins combines Geosat altimeter profiles of sea-surface topography in the Southern Ocean (south of 60°S) with Advanced Very High Resolution Radiometer (AVHRR) data from Antarctica.

The PLATES 2014 Atlas of Plate Reconstructions (550 Ma to Present Day), PLATES Progress Report No. 374-0215

This atlas presents plate reconstructions from 550 Ma to the present-day derived by the PLATES Project, Institute for Geophysics, The University of Texas at Austin. The atlas was made possible through the scientific contributions of many researchers, from UTIG and from other institutions. Their efforts are highly appreciated by the members of the PLATES research team. The atlas was created using the PaleoGIS (paleogis.com) for ArcGIS plate reconstruction software by The Rothwell Group, L.P., and the GPlates (http://www.gplates.org/) plate reconstruction software. For more information, contact plates@ig.utexas.edu.

Paleogeographic Reconstructions With Sediment Isopachs

This atlas displays a series of reconstructions from 1 00 Ma to Present. The data displayed include coastlines and sutures (from coasts25.1995) and sediment isopachs (from isopachs.1 995). In the summer of 1994, Mobil Exploration and Producing Technical Center of Dallas, TX, gave the PLATES Project a global digital set of sediment isopachs. The data are now in PLATES format and have been assigned plate identification numbers but have not yet been assigned ages. Figure 1 (0 Ma) shows how the data have been assigned to plates. Figures 2 through 12 present reconstructions from 100 Ma to Present. The isopachs were colored according to thickness (in kilometers). For more information, contact plates@ig.utexas.edu.

Large Igneous Provinces: Map and Data

The PLATES Project compiled digital data representing the location of large igneous provinces (LIPs). This report includes a map of the data, the digital data, and a bibliography.

Present-day Plate Boundaries (poster)

This poster shows present-day plate boundaries. The background image is topography/bathymetry of the world as derived by Smith and Sandwell, 1997. Earthquake epicenter locations were downloaded from NEIC (http://neic.usgs.gov) on Marcy 19, 2010. Volcano locations were downloaded from the Global Volcanism Program (http://www.volcano.si.edu) in June 2009.

Combining Burial Histories and Sedimentary Basin Rotations (PLATES Progress Report No. 267-0502)

The PLATES Project produced global plate reconstructions. Mike Horn provided the project with a dataset of 845 burial history case studies. The dataset included oil generation tables, vitrinite reflection calculations, references, thermal histories, natural fracture predictions, oil generation calculations, simultaneous fractue prediction, standardized locations maps, and basin and sedimentary province classification. This poster incorporated the thermal and burial histories into plate reconstructions for added dimensions of paleodepths and temperatures.