<SEC-DOCUMENT>0000902664-21-004320-index.html : 20210923
<SEC-HEADER>0000902664-21-004320.hdr.sgml : 20210923
<ACCEPTANCE-DATETIME>20210923172232
ACCESSION NUMBER:		0000902664-21-004320
CONFORMED SUBMISSION TYPE:	SC 13D/A
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20210923
DATE AS OF CHANGE:		20210923

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ION GEOPHYSICAL CORP
		CENTRAL INDEX KEY:			0000866609
		STANDARD INDUSTRIAL CLASSIFICATION:	OIL AND GAS FIELD EXPLORATION SERVICES [1382]
		IRS NUMBER:				222286646
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13D/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-41602
		FILM NUMBER:		211273285

	BUSINESS ADDRESS:	
		STREET 1:		2105 CITYWEST BLVD
		STREET 2:		SUITE 100
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			770422855
		BUSINESS PHONE:		2819333339

	MAIL ADDRESS:	
		STREET 1:		2105 CITYWEST BLVD
		STREET 2:		SUITE 100
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			770422855

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	INPUT OUTPUT INC
		DATE OF NAME CHANGE:	19930328

FILED BY:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Gates Capital Management, Inc.
		CENTRAL INDEX KEY:			0001312908
		IRS NUMBER:				133886865
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13D/A

	BUSINESS ADDRESS:	
		STREET 1:		1177 AVE. OF THE AMERICAS
		STREET 2:		46TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10036
		BUSINESS PHONE:		212-626-1421

	MAIL ADDRESS:	
		STREET 1:		1177 AVE. OF THE AMERICAS
		STREET 2:		46TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10036

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Gates Capital Management Inc.
		DATE OF NAME CHANGE:	20041228
</SEC-HEADER>
<DOCUMENT>
<TYPE>SC 13D/A
<SEQUENCE>1
<FILENAME>p21-2211sc13da.htm
<DESCRIPTION>ION GEOPHYSICAL CORPORATION
<TEXT>
Document 1 - file: p21-2211sc13da.htm

</DOCUMENT>
</SEC-DOCUMENT>