Quick
Search: 		  
advanced search
 GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help 
  Petroleum Geoscience   Email Content Delivery
JOURNAL HOME HELP CONTACT PUBLISHER SUBSCRIBE ARCHIVE SEARCH TABLE OF CONTENTS
Petroleum Geoscience; January 2004; v. 10; no. 1; p. 43-52; DOI: 10.1144/1354-079302-547
© 2004 Geological Society of London
This Article
Right arrow Figures Only
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Pranter, M. J.
Right arrow Articles by Davis, T. L.
Right arrow Search for Related Content

Original Article

Anhydrite distribution within a shelf-margin carbonate reservoir:San Andres Formation, Vacuum Field, New Mexico, USA

Matthew J. Pranter1, 2, Neil F. Hurley1 and Thomas L. Davis1

1 Colorado School of Mines, Department of Geology and Geological Engineering, Golden, Colorado, 80401 USA(e-mail: matthew.pranter@colorado.edu; nfhurley@mines.edu; tdavis@mines.edu)
2 Present address: University of Colorado at Boulder, Department of Geological Sciences, Campus Box 399,2200 Colorado Avenue, Boulder, Colorado, 80309-0399 USA

Anhydrite cement causes significant heterogeneity within the San Andres reservoir of the Vacuum Field where it is associated with faults, fractures, karst zones and highly cemented dolomite intervals. The primary reservoir rocks within the Central Vacuum Unit of the Vacuum Field are dolomitized peloidal packstones, skeletal and ooid grainstones and fusulinid packstones. These rocks alternate with lower reservoir-quality dolomite intervals with variable amounts of anhydrite cement. Nodular and pore-filling fabric-selective anhydrite cements are common within the reservoir interval. Cross-plots of apparent matrix grain-density versus apparent matrix volumetric cross-section ({rho}maa–Umaa cross-plots), combined with Vp/Vs seismic attributes and core data, provide insight into the vertical and lateral distribution of anhydrite within the San Andres reservoir. Anhydrite is generally concentrated in thin depositional cycles or intervals that are separated by relatively anhydrite-free cycles that exhibit relatively higher porosity and permeability. Lower Vp/Vs values correspond to higher percentages of anhydrite and are useful formapping anhydrite distribution. This evaluation of anhydrite distribution providesan estimate of the significant cementation-related heterogeneities within the reservoir that is useful for development-well planning and to target areas of bypassed pay.

KEYWORDS: San Andres, carbonate, anhydrite, cement






JOURNAL HOME HELP CONTACT PUBLISHER SUBSCRIBE ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2009 by Geological Society of London