New Mexico Bureau of Mines & Mineral Resources

A DIVISION OF NEW MEXICO INSTITUTE OF MINING & TECHNOLOGY

Geology of Garfield quadrangle, Sierra and Dona Ana Counties, New Mexico

by William R. Seager and Greg H. Mack

Department of Earth Sciences, New Mexico State University, Las Cruces, New Mexico 88003

SOCORRO 1991 11

NEW MEXICO INSTITUTE OF MINING & TECHNOLOGY Laurence H. Lattman, President NEW MEXICO BUREAU OF MINES & MINERAL RESOURCES Charles E. Chapin, Director and State Geologist

BOARD OF REGENTS Ex Officio Bruce King, Governor of New Mexico Alan Morgan, Superintendent of Public Instruction Appointed Steve Torres, President, 1967-1997, Albuquerque Carol A. Rymer, M.D., President-Designate, 1989-1995, Albuquerque Lt. Gen. Leo Marquez, Secretary/Treasurer, 1989-1995, Albuquerque Robert 0. Anderson, 1987-1993, Roswell Charles Zimmerly, 1991-1997, Socorro

BUREAU STAFF Full Time ORIN J. ANDERSON, Geologist ROBERT W. EVELETH, Senior Mining Engineer NORMA J. MEEKS, Senior Pub./Bus. Office Clerk RUBEN ARCHULETA, Metallurgical Lab. Tech. Lois GOLLMER, Staff Secretary BARBARA R. POPP, Chemical Lab. Tech. II AUGUSTUS K. ARMSTRONG, USGS Geologist IBRAHIM GUNDILER, Metallurgist MARSHALL A. REITER, Senior Geophysicist GEORGE S. AUSTIN, Senior Industrial Minerals Geologist WILLIAM C. HANEBERG, Engineering Geologist JACQUES R. RENAULT, Senior Geologist AL BACA, Maintenance Carpenter II JOHN W. HAWLEY, Senior Env. Geologist JAMES M. ROBERTSON, Senior Economic Geologist JAMES M. BARKER, Industrial Minerals Geologist CAROL A. HJELLMING, Assistant Editor JANETTE THOMAS, Cartographic Drafter II MARGARET W. BARROLL, Post-Doctoral Fellow GRETCHEN K. HOFFMAN, Coal Geologist SAMUEL THOMPSON III, Senior Petrol. Geologist PAUL W. BAUER, Field Economic Geologist GLEN JONES, Computer Scientist/Geologist REBECCA J. TITUS, Cartographic Supervisor ROBERT A. BIEBERMAN, Emeritus Sr. Petroleum Geologist FRANK E. KOTTLOWSKI, Emeritus Director and State Geologist JUDY M. VAIZA, Executive Secretary LYNN A. BRANDVOLD, Senior Chemist ANN LANNING, Administrative Secretary MANUEL J. VASQUEZ, Mechanic I RON BROADHEAD, Petrol. Geologist, Head, Petroleum Section ANNABELLE LOPEZ, Petroleum Records Clerk JEANNE M. VERPLOEGH, Chemical Lab. Tech. II MONTE M. BROWN, Cartographic Drafter II THERESA L. LOPEZ, Receptionist/Staff Secretary ROBERT H. WEBER, Emeritus Senior Geologist KATHRYN E. CAMPBELL, Cartographic Drafter II DAVID W. LOVE, Environmental Geologist SUSAN J. WELCH, Assistant Editor STEVEN M. CATTIER, Field Economic Geologist JANE A. CALVERT LOVE, Editor NEIL H. WHTTEHEAD, III, Petroleum Geologist RICHARD CHAMBERLIN, Field Economic Geologist WILLIAM MCINTOSH, Research Geologist MARC L. WILSON, Mineralogist RICHARD R. CHAVEZ, Assistant Head, Petroleum Section CHRISTOPHER G. McKEE, X-ray Facility Manager DONALD WOLBERG, Vertebrate Paleontologist RUBEN A. CRESPIN, Garage Supervisor VIRGINIA MCLEMORE, Geologist MICHAEL W. WOOLDRIDGE, Scientific Illustrator Lois M. DEVLIN, Director, Bus./Pub. Office LYNNE McNEIL, Technical Secretary JIRI ZIDEK, Chief Editor—Geologist

Research Associates CHRISTINA L. BALK, NMT ALONZO D. JACKA, Texas Tech. HOWARD B. NICKELSON, Carlsbad WILLIAM L. CHENOWETH, Grand Junction, CO BOB JULYAN, Albuquerque GLENN R. OSBURN, Washington Univ. RUSSELL E. CLEMONS, NMSU SHARI A. KELLEY, SMU ALLAN R. SANFORD, NMT WILLIAM A. COBBAN, USGS WILLIAM E. KING, NMSU JoHN H. SCHILLING, Reno, NV CHARLES A. FERGUSON, Univ. Alberta MICHAEL J. KUNK, USGS WILLIAM R. SEAGER, NMSU JOHN W. GEISSMAN, UNM TIMOTHY F. LAWTON, NMSU EDWARD W. SMITH, Tesuque LELAND H. GILE, LAS Cruces DAVID V. LEMONE, UTEP JOHN F. SUTTER, USGS JEFFREY A. GRAMBLING, UNM GREG H. MACK, NMSU RICHARD H. TEDFORD, Amer. Mus. Nat. Hist. RICHARD W. HARRISON, Tor C NANCY J. MCMILLAN, NMSU Tommy B. THOMPSON, CSU CAROL A. HILL, Albuquerque

Graduate Students WILLIAM C. BECK ROBERT L. FRIESEN GARRETT K. Ross JENNIFER R. BORYTA ROBERT S. KING ERNEST F. SCHARKAN, JR. STEPHEN G. CROSS DAVID J. SIVILS

Plus about 30 un