LIIT'L^"EL ITP
Jed R. Maebius y
E
a
.
.
; :s"
. ! . :_; , =: "A
4. _ t ._. _.. , .f L, F .d f ^ ;
Ij: r
. _ .a1'.:
_..-,{,
; ,
f -
win.
PKOIliTy OF
, _.
F . - ,'
". _
.. f,- y
1817 4-,' i 2W . I!- J : *A l '1 VE TAR
r
: r. '
1 ., V K. -Thy 'v , -' 4t *-'~~'~'t~V
+ .:.-- ,3s Mai ,> _ ,_"3 ' ,_ -411 '7~ i.~4j '2> -~
, 2 R' .
_ a2 , < .. i T~xE PORTER OIL F IELD by l~ed B-. Maebiua
Department of Geology University of Miohigan ray, 1935 i TABLE OF CONTENTS
INTRODUCTION
Location and Extent of the Area. 1 Events Leading to the Discovery of Oil 1
Source of Geologic Data 2 Acknowledgements 3 STRATIGRAPHY
Early Paleozoic Rocks 3 Devonian System 4
Mississippian System 7
Pennsylvanian System 9
Permo-Carbonif erous(?) System 10 STRUCTURE
Regional Structure 14 Local Structure 15
Porter Oil Field Structure 15 Major Trend, Size, and Relief 15
Minor Variations 17
Thinning and Thickening of Formations 18 Unconformities 18
Origin of the Structure 20
Theory of Differential Compaction 20 Solution Theory 21 Theory of Norizontal Compression 21.
Movements in the pre-Cambrian Rocks 22 U
Production 24 Acid Treatment 24
Properties of~ the Oil 26
Future of the-Field 26 " i
LIST OF FIGURES
Tab le I 11, 12, 13 Figure I 16' Figure II 23 Figure III 25 iv
PLA'TES
PLATE I Subsurf'ace Structural Contours Lower Marshall rormation
PLATE II Subsurface Btruc tural1 Uontours Traverse Yormat i on
PLATE III Subsurf ace struc tural1 Uontours Dundee Formation
PLATE IV Section A-A Across Porter Oil field THE PORTER OIL FIELD
INTRODUCTION
Location and Extent of the Area
The Porter oil field is located in Porter township:,
Midland County and extends in a northwest direction aeros Porter township and into the northeast corner of Jasper town-
ship and the southeast corner of Greendale township. The
extension of the pool four miles to the northwest ih Jasper
and Greendale townships is called the lost field. Six miles farther along the same trend to the northwest lies the Green-
dale field.
The Porter oil field has an estimated produing
area of 3000 acres, but inasmuch as the structure has not yet been completely defined, the potential acreage will be increased
with future drilling.
Eents Leading to the Discovery of Oil
On November 14, 1931, the Michigan Facific 01 and
Gas Company brought in an oil well on the James hi. Otway, ir., lease in tnre W*, W4jN,LW' of oeetion 26. This location is on
the extreme southeast of the proven field. The well made ll1 barrels at a depth of 3417 feet, the oil coming from the vundee
formation. In December, 1932, the Pure Oil Company brought in
the Mattie Yost No. I in 51, Wi, t1* of Section 35, Greendale 2.
township. This well is about five miles northwest from the discovery well in what is now called the Yost field. The
initial production of this well was 1155 barrels. It was after the discovery of this well that a structure of consider-
able extent was indicated. On February 27, 1933, the Michigan Pacific Oil and Gas Company brought in the J. H. Otway well
in the *So* NE.t SW.A sec. 22. This well made an initial
production of 300 barrels and after drilling 35 feet deeper
and treating the well with acid, it made 3200 barrels in 36
hours. The discovery of this well was the beginning of
intensive drilling operati ons in the surrounding region,
especially in section 22. The logs from th6lbriftetellesof the- Dow Chemical Company, located in a line along the boundary between Jasper and Porter townships, were also used in working out the structure.
Source of Geoloc Data
The logs of the oil wells,which serve as the
principle basis of this report, were obtained from the Oonserva-
tion Department of the Eichigan Geological Survey, Lansing,
Michigan. Well samples were obtained from the Pure Oil Company,
Saginaw, Michigan. These samples were used in describing the formations, and also in determining by chemical analysis that the pay horizon was dolomitic. 3.
Acknowledgments
Many helpful suggestions for the preparation of this paper were furnished by the staff of the Department- of
Geology, University of Michigan. Dr. R. B.. Newcombe, George
Lindberg, and F. R. F'ye of the Michigan Geological Survey were very generous in giving helpful suggestions and making
available the materials necessary for the work. W. A. Thomas
of the Pure Oil Company furnished well samples and information
that was necessary in working out the stratigraphy of the area.
STRATIGRAPHI
Early PaleozotieRocks
The sedimentary rock sequence as described below
has been compiled directly from the data derived by the study of the well logs of the field. These wells Include only the
formations down to the Dundee, the producing horizon.
Newcombel and others2 have already described the stratigraphy
INewcombe, R. B., Oil and gas fields of Michigan: Michigan Geol. and Biol. Survey Pub. 38, Geol. Ser. 32, pp. 19-90, 1933. 2 Lane, A. C., and Seaman, A. E., Notes on the geological section of Michigan: Jour. Geology, vol. 15, p. 686, 1907.
4mith, h. A., A report on Michigan limestones: Michigan Geol. and Biol. Survey Pub. 21, Geol. Ser. 17, Prt II, pp. 153-257, 191. 4.
in detail and it is only in certain refinements that the present data is original. The pre-Cambrian rocks that under-
lie unconformably the sedimentary rocks of the Michigan
synclinal basin are of igneous and metamorphic varieties.
The total thickness of the Paleozoie sedimentary rocks in
the central portion of the basin is probably over 12,000 feet.
They consist of sandstones, shales, and limestones. The rocks
of Cambrian age, known principally from outcrops in the Upper
Peninsula, are sandstones with a thickness of about 1500 feet.
The Ordovician system also does not outcrop in the lower peninsula but it has been penetrated by drilling and has an estimated thickness of 1600 feet. It is made up of shale and
limestones with thin beds of sandstones. The possible oil
horizon in this system is the Trenton formation of middle Ordovician age. This is a massive dolomitic limestone with
an average thickness of 600 feet. The Silurian rocks of
Michigan are largely limestone, dolomite, salt, and gypsum.
The conditions of evaporation that caused the salt and gypsum deposits are duplicated several times during the remainder of the Paleozoic era in Michigan.
Devonian 51 tem
The Devonian period began with the deposition of a basal sandstone and ended with the formation of beds of black and gray shales and dolomitic limestones. These beds 5.
have been divided into a number of formations, of which the bylvania sandstone is the lowest. In places it is absent, but elsewhere ranges in thickness up to 300 feet. The Detroit River series overlies the Sylvania and consists of dolomite, gypsum, and salt. It has an average thickness of 800 feet. The next two higher formations, the Oriskany and Mackinac consists of sandstone, oherty limestone, and dolomite. There is some doubt as to the correlation of the Oriskany with the true
Oriskany of surrounding states. The doubtful Oriskany is only 5 feet thick and is overlain by the Mackinac, Which may hpve a maximum thickness of 300 feet, but again may be totally absent. The Dundee formation which overlies the Mackinac unconformably and is the producing horizon of the Porter oil field, varies in thickness from 300 feet in the Saginaw region to 50 feet in central and western Michigan. The irregularities of the Mackinac erosion surface on which the Dundee was deposited, together with an episode of erosion at the close,of
Dundee deposition, accouht for the varying thickness of the latter. The Dundee of the northern part of the state does not correlate with the Dundee in the southern part and there seems to be a different fauna present in the two regions. These faunal elements are thought to be due to the presence of local basins and barriers during deposition. The lithologic characteristics are similar throughout the state. The rock is gray to buff, cherty, crystalline, fossiliferous limestone. There is a 6.
dolomitic bed near the base that grades into a sandstone in some localities. The porous zones that serve as reservoirs in the oil producing areas also are dolomitic and contain much bituminous matter. A drilling sample from the producing horizon may be a buff-colored limestone, but upon treatment with HG1 acid, will yield globules of oil. The Bell shale occurs above the Dundee at the base of the Traverse formation and regionally is a wedge shaped formation thinning to the southwest. The shale is a blue gray to dark gray calcareous rock, usually black at the base. It is locally absent and
in these places it is very difficult to distinguish the base of the Traverse from the top of the Dundee. The thieknesw of the shale varies from 60 to 80 feet but in many of the well logs the drillers either fail to recognize the Traverse-
Bell contact or place the top of thefell shale up in the lower
shale bed of the Traverse. The Traverse formation occurs without a break
throughout the Elohigan basin. It ia made up of alternating beds of shale, limestone, and dolomitie limestone. It has a eharacteristic blue color that helps to distinguishhit from the more buff colored Dunclee below. The average thicknese for the central lichigan area is about 600 feet. The top of the Traverse is very irregular and probably represents an errosional surface. The Antrim shale is a dark brown to black shale containing many concretions of pyrite and bituminous 7.
limestone. These concretions occur throughout the formation but are more characteristic at the base. The average thickness of the Antrim shale in the Porter region is over 400 feet. The basal Herea is composed of a blue shale and may be erroneously classed as part of the Antrim by the drillers.
Mississippian yatem
The Mississippian period is characterized ik central and western Michigan by a succession of sandstones. Overlying the sandstone and shale sequence is a continuous limestone deposit which marks the close of the Missiasipian period.
£ollowing the deposition of the limestone, the area was up- lif ted and eroded, removing many of the upper formations and bringing about a pronounced disconformity. There is some doubt as to the exact position of the base of the Mississippian because some diagnostic RissisutpWian fossils have been found tn the upper Antrim beds. In the
Porter area, the Berea seems to occur at the base of the Mississippian, but in some logs the aedfard is represented underlying the erea. The Bedford formation is a gray shale and is about 45 feet thick when recognized by the drillers. The Berea is a fine grained sandstone separated by thin layers of shale and limestone and has an average thickness of 75 feet.
The greatest thickness occurs in the saginaw region. The formation thins rapidly to the west where it disappears entirely. 8.
The Sunbury formation occurs above the Berea and is a black shale that averages 10 feet in thickness in the central ichigan area. rhis formation does not outcrop in
Michigan and has not been mapped as a separate formation.
The Coldwater formation is the thickest series or shale beds in Michigan and occurs regularly throughout the Aiehigan basin. in the eastern part of the state, it is entirely shale but changes to a calcareous shale and limestone to the west. It is over 1000 feet thick in the Porter area and contains a re d shale bed near the top. The greatest thickness is represented by a black shale.
The Marshall formation Is divided into two parts. 'the upper division is called Napoleon and the lower, Lower
Marshall. Thomas 3 has also proposed another division in the
Thomas, W. A., A study of the Marshall formation in Miehigan: Rieh. Acad. Set., Arts and Letters, Papers, vol. 14, p. 493, 1921. Napoleon as evidenced by an unconformity. A widespread uplift took place at the beginning of the Marshall as is evidenced by the
Conglomerate at the base in the "Thumb" area. The sea transgressed westward and the Marshall grades into a sandstone that include several red beds. These local red beds indicate oxidation and the presence of iron in the seas of that time. In the central
Michigan area, the red bed at the top of the Lower Marshall is continuous and easily spotted by the drillers. This "Red Roo* is used as a key horizon for contouring the structure in the 9.
Porter rield. 6ee 2late 1. There was renewed upwarping at the close of Napolean deposition, which isolated the Michigan basin from the seas to the south. In this confined basin the
Michigan formation was deposited. The sandstones of the
Napoleon are continued in the basal beds of the Miehigan and may be reworked Marshall. During the middle of the period,
4 Lindberg, (., oral communication. gypsum was deposited. These gypsum beds are present in local synclines but absent on the anticlines. This would indicate continued structural relief as deposition was taking place.
The sandstone at the base of the Michigan is also absent on some of the structures in the central Michigan area.
During the succeeding time, new sea connections were opened to the south. in these the Bayport formation was deposited. The Bayport includes alternating limestones, dolomites, and white sandstones. At the close of bayport time, the entire basin was raised above water and active streams ervdedd deeply into the Bayport and Michigan formations. The flow of these streams was directed by the existing structures and accounts for the spottiness of the bayport.
Pennsylvanian ystem
The Pennsylvanian age opened with a shallow sea Which formed continuous sandy shore de osite. The Parma formation at the base is a conglomerate. It filled the uneven erosional surface of the Mississippian rocks. rollowin6 Parma 10.
deposition, the basin became a great shallow area supporting vegetation in the swampy regions. This resulted in coal deposits which occupy the local basins but do not conform to the older structures present. The deposits were brought in by streams as is evidenced by sandstones and shales. These beds together with the coal series constitute the Saginaw formation.
In the Porter area this formation is over 400 feet thick, but throughout the basin it varies in thickness depending on the structural oonditions which existed before its deposition.
Permo-Carboniferous(?) Sys tem
At the close of Saginaw time, Michigan was again raised above water and an unconformable and unnamed series of red sandstones was deposited with the greatest thickness to the northwest. The basal russet colored sandstone has been called Woodville and correlated with the Permian "Bed Beds" of the southwestern United States. Higher in the formation, there are alternating beds of gypsum and sandstone indicating desert conditions. The "Red Beds" are the last consolidated rocks that are now present in Michigan. A detailed log as compiled from the driller's report is included to show the stratigraphic sequence in the Porter pool. See Table I. 11.
Porter (midland) LmAr Oil & Refininlg Cos able B. Finch #1 Permit #1919 Drilling Contractor: Lupher Drilling Co.
4cation: NF4 S'Jv SBr section 21., T.l3N., R.lW1.'s 9901 from south end 990' from west line of quarter section.
Sevation: 688,2 feet above sea level.
Scord by Lyle Wi. Price from driller's log:.t Thickness Dept (Feet) (Feet) leistocene: Drift De-posits: Sand; gravel 6o 6o Clay 146 106 Gravel 36 1~42 Clay 86 228 "Shell" 5 233 ermoCarbonif erous (7) "Red Beds" Red rock 2 5 20 25 -Sandstone, red (Wood~ville) 2 7 efnsylvanian: Saginaw Formationt Sandstone, white 70 35 Shale, blue530 Sandstone, white 8 3 Shale, blue 40470 Shale, blue 70 5140 Sandstone, white 0o59 Shale, blue 4 595 Shle black 15 610 Shale, white 10 620 Shale, gray 52 672 Limestone, gray 13 685 Shale, gray 6 691 'i. sissip ian: Bayaort Formation: Limestone, gray 2 2 Michigan Formation: Shale 10 730 Shale, green 5730 Sandstone 5 Shale, green8 4 Gy-psum 2 750 Shale, blue 13 7 63 Shale ,'gray 40803 Sable2 805 Shale,. blue 6 9 SablueS ray; limestone "shells"6 27 972 Sandstone, gray 2 7 Sandstone 3 g Limestone 10 9850 Shale, black 10 12. Page 2 Porter (Midland) Emnire Oil & Refining Cc. ble B. Finch #1 Permit #1919
Thickness Depth (Feet) (Feet) Michigan Formation: (cont'd) Limestone 7 1007 Shale, black 1025 Naoleon Formation: Sandstone, gray 20 1045 Sandstone 55 1100 Red rock 2 1102 Sandstone 35 1137 Sandstone 53 1190 No record 3 1193 Lower Marshall Formation: Sandstone, red 51 1244 Red rock 14 1258 Coldwater Formation: Shale, blue 5 1263 Shale, black 5 1268 Shale, gray 27 1295 Shale, blue 25 1320 Limestone 8 1328 Shale, reddish 6 1334 Shale, blue 28 13 2 Shale, gray 78 1440 Shale, blue 50 1490 Limestone 3 1493 Red rock 7 1500 Limestone 8 1508 Limestone, hard 8 1516 Red rock 5 15a Shale, blue 42 1563 Shale, gray 287 1850 Limestone 11 1861 Shale, gray 149 2010 Limestone 5 2015 Shale, gray 235 2250 Limestone 5 2255 Shale, gray 35 2290 Sunbury Formation: Shale, black 15 2305 Berea Formation: Sandstone (0. & G. 2305-15) 55 2360 Bedford Formation: Shale, gray 5 ?365
1n ian: Antrim Formation: Shale, brown 10 2375 Shale, gray 45 2420 Shale, brown 375 2795 No record 2 2797 Traverse Formation: Limestone 2830 Shale, gray 2870 Limeston 314 3184 Shale, gray; limestone Rshells" 21 3205 13.
Page 3
Porter (Midland) Empnire Oil & Refining Co. ble B. Finch #1 Permit #1919 Thickness Depth (Feet) (Feet) Traverse Formation: Limestone; shale; "shells"' 27 3232 Shale, gray 15 32147 Limestone "shells"; shale 146 3293 Shale, gray 73 336 Shale, black; limestone 9 3375 Thundee Formation: Limestone 52 31427 TOTAL D 'TH 31427 6ng record: Commenced: t29-34 2 " Initialomle e:763'Production: 5/9" 12691 115 Bbls. 3/16" 3379' 14
5TRUCTURE
Regional Structure
The major structural feature of the lower peninsula of Michigan is a dlightly.elqngated, shallow basin with the main axis extending in a northwest, southeast direction. The sedimentary formations thicken, in general, towards the center of the basin. Throughout the deposition of the sedimentary rocks, there were periods of uplift to the south that cut off the invading seas and left the basin isolated. According to
Newcombe5 , this isolation occurred four times, in late Silurian, Newcombe, R.Bo., Structure and accumulation in the Michigan "Basin" and its relation to the Cinc nnati arch: Amer. Assoe. in early Devonian, in late Mississippian, and in the "trmo-
Carboniferous.* Newcombe6 has suggested the origin of the
60p. cit.,. pp. 537-541. Michigan synclinal basin as being directly related to the major structural regions surrounding the area. The Wisconsin land mass on the west, the Kankakee arch of Indiana on the southwest, the Cincinnati anticline on the southeast, and the Laurentian land mass on the northeast, were known positive elements affecting the region. The Illinois-Indiana aoal basin to the southwest, the western part of the Appalachian coal basin in Ohio on the southeast, and the Lake Superior Geosynclinecon the north were known areas of negative character that were frequently: confluent with the sinking Michigan basin. The '5. relation of these structural features has been discussed by
Pirtle. The cause of the downwarping of the Michigan syn-
7 Pirtle, . C., Michigan structural basin and its relationship to surrounding areas: Bull. Amer. Assoc. Petrol. Geol., vol. 16, No. 2. Pp. 145-152, Feb. 1932. clinal basin is as yet unknown. The problem may be closely related to the general one of geosynclinal formation which cannot be diseussed here.
Local Structure
Many minor folds are superimposed on the major structure and are parallel to the long axis. ee Figure 1. Newcombe8
8 Newcombe, R. B., Structure and accumulation in the Michigan "Basin" and its relation to the Cincinnati arch: Amer. Assoc. Petrol.-Geol AuE.p. 535, Aug. 1934. believes that these smaller structures in Michigan were controlled by severak factirs abd should not be attributed to one major cause.
He further contends that the central part of the basin was more stable than the margins, because the folds in the central area are more symmetrical and trend in one direction. Newcomb's regional structural contour map drawn on top of the Traverse formation shows the alignment of the minor folds with regularity in the central part of the basin and with irregularity around the margins. Porter Oil Field structure
aJor Trend, Size, and Relief The structure of the Porter oil field trends in a northwest, southeast direction. It is approximately 5 miles long and 2 miles wide with a saddle at each end. The structure 16.-
SBSURFACE STRUCTU AL CONTOUR MAP ICHUGAN CONTO RSDRAWN ON TOP
TRAN ERSE FORMATION CONTOUR INTERVAL- 00 FEET
4-SCALE ...... MILES By I) \)RKNEWCOMSE 747 133
IN.cm DEFINITE -
N31 N s rwtsnnso' .01 it.aL .lz V i MSc. NT T wio veam n mc e0 tSitO o tpot tOSSf CL
CGWLmp 'Wv' - /-/-' /" r %%-1 \CKA .-.- -, 'N N atNAtN Ia S7IVC1E 1'f''r f j ''TI 4 % AID A
A4
N N,- t~ CA Z'% ___ NI. .7 1 .
N-. j - N' N't
-I ItAMt- i N,2~ V4A t%"t i Ni-N \iN, ~K;$ 4 _ 'I, "S i. INi/~
00' NL \
oI~4~~4 u.opr r..r. rt " # & 10 10.OW7 00
Flgure I 17. rises to the southeast, and drops off to the northwest towards the Yost field. This major trend is shown by the structural contour map drawn on top of the "Red Rock." See Plate I.
This structure is asymmetrical with the steepest dip to the southwest. As brought out by the structural maps, the dip of the Porter structure becomes steeper with depth to the margin of the contoured area, but this conclusion is based on only a few wells that have been drilled off structure. (Plates
I, II, III) The dip on the southwest flank of the anticline is from 120 to 170 feet to the mile while the dip to the northeast is 40 to 75 feet to the mile. A series of small crestal closures ranging from 20 to 50 feet are conspicuous.
There appears to be a large synclinal basin to the southwest of the structure and a nose coming from the southeast with the dip to the northwest. to the northeast the moderate dip seems to be influenced by the regional dip towards the center of the basin.
Minor Variations Superimposed on the major structure is a series of small sags and swells previously mentioned. There are four of these that are quite regular and pronounced and are represented on all of the formations (Plates I, II, III). They extend transversely across the larger structure. Interspersed between these cross folds are a great many smaller domes and synclines that apparently do not follow any definite direction of alignment. The accumulation of oil seems to have taken place 18.
along these major cross folds, and productive wells extend farther down the structure where these cross folds occur.
The smaller domes and synclines do not affect the accumulation of oil on the 'structure. Thinning and thickening of formations: The formations thicken off structure, especially to the southwest. in the north-south section across the structure the "Red Rock" formation thickens over a hundred feet off structure within a distance of 5 miles (Plate I). The rest of the formations also thicken but not as much as the "Red Rock." This evidence cannot be conclusive because of the lack of wells off structure. it may be a local thickening due to an erosional feature. However, Miss Leaton9 in making a study of the Traverse
9Leaton., Miss. Oral communication. formation for the Gulf Oil Company found that this formation thickened off structure in several of the pools of the state. Unconformities: The unconformities represented in the Porter field are probably an important factor in modifying the structural features and the porosity of the reservoir rock. The breaks that are evident in the wells drilled in this area are the Dunde-Traverse disconformity, the Berea-Coldwater disconformity, the Marshall-Grand Rapids unconformity, and the
(rand iapids-Parma disconformity. The Dundee-Traverse break in the central part of the Michigan basin has been described by Niewcombel 0 10 Newcombe, R. H., Middle Devonian unconformity in Michigan, bull. Geol. Soc. Amer., vol. 41. ;'734-3, 1930. 19.
The Dundee fromation ranges from a few feet to 200 feet within a short distance, or may even be totally absent. This formation is present over the entire Porter structure, the bottom of the Dundee not having been reached in any of the wells. The Berea-Coldwater break was caused according to Newcombe by a tilting of the basin to the southeast. The unconformity is noticeablp in the western part of the state but not in the central area. The Marshall-Grand kapids disconformity represents a period of considerable erosion and the reworking of the upper Marshall sandstone. Lindberg1 1 has 1 1Lindbers G. Oral communication. suggested that the Michigan "stray sand" is reworked Marshall.
The stratigraphic evidence of this break has also been reviewed by Thomas.1 2 He found that there was an overlapping of the 12 Thomas, w. A., A study of the Marshall formation in Michigan: Mich. Acad. Sci., Arts and Letter, Papers, vol. 14, pp. 487-498, 1930. upper Marshall formation to the west. He also suggested a break within the upper Marshall.
The Grand tapids-?arma break occurs at the Mississippi-
Pennsylvanian contact which is a zone of considerable erosional relief. The evidence of this break is shown where the Parma formation is deposited unconformably on the upper marshall formation and in some instances is entirely absent.
The unconformities in the Michigan basin have affected structure by causing regional thinning of formations and over- lapping of sandstone lenses. Uneven deposition over the local 20.
structures depended on the physiography of the local folds when sediments were subsequently deposited over them. That these folds existed during deposition, is evidenced by the thick deposits of gypsum in the synclines and the thinning of the Marshall sandstone on top of the anticlines (Plate IV). Origin of the Structure
The origin of the Porter structure must necessarily be considered in relation to the regional structure of the Michigan basin. Several theories have been proposed to explain the problem but none appears to be entirely acceptible. Each will be discussed but no attempt will be made to draw definite conclusions. Theory of differential compaction: The evidence in favor of this theory is derived from two sources, first, the general thickening of the formations off structure, and second, the steepening of the dip of the structure with increasing depth. The cross-section of Plate IV illustrates the thickening of the Lower Marshall formation off the southwest flank of the fold. The conclusion is not as definite as the diagram would indicate, however, because of the scarcity of well records off structure. A comparison of Plates I, II, and III shows the increasing relief from the Lower Marshall to the Dundee formation,
2000 feet below. An objection to this theory is the fact that the sandstone members thicken a great deal more than the shale members. This would not occur if the entire sedimentary series was deposited before compaction commenced. If, however, compaction 21.
had occurred at the same time as deposition, the sediments may have had an originally greater thickness off than on structure.
This latter interpretation seems probable because of the distri- bution of gypsum in the basins and not on the anticlines.13
1 3Newcombe, R, B,9 Oil and gas fitelds of Michigan: Michigan Ge~1. and Biol. survey, Pub,,38, Geol. Ser. _32. p. 8311 L932* The Parma sandstone also was deposited in the structural synclines. Unconformities would also alter the sequence of an ideal structure by compaction. The problem should be studied in other structures before a definite conclusion is attempted.
Solution theory: The solution of salt beds along planes of faulting and fracturing has been proposed by Newcombe.14
14~ORcit. 9-*R-118.
The solution is supposed to occur some time after salt deposition but before the overlying load was very great. This resulted in a subsequent settling of the overlying formations. Thin theory cannot here be applied with any conviction because the wells have not penetrated the underlying salt-bearing formations. here again, evidence for or against the theory must be drawn from other regions. Theory of horizontal compression: Long parallel and perhaps asymmetrical folds with high dips are usually the result of horizontal compressional forces. In the light of aceumul.ating data, the folds, of the Michigan basin appear to be neither elongated nor parallel and certainly do not have high dips. With future details from drilling, this theory can be more thoroughly tested. 22.
Movements in the pre-Cambrian rocks: Movements along
a few major faults or regionally distributed along systems of
joints in the pre-Cambrian crystalline rocks over which the Paleozoic sedimentary rocks lie, may have caused the local
structures of the michigan basin. The movements must necessarily
have been post-Proterozoic, either recurrent during ialeozoie
time or post-Paleozoic. the fault displacements may have been
vertical or horizontal or a combination of both. The veneer of
Paleozoic sediments is considered to have flexed over the under- lying fault scarps or folded along lines of compressional stress.
The most promising conception of pre-ambrian rock movement is that of a few major northwest trending faults along which horizontal displacement occurred intermittently through
Paleozoic time. Such movement would induce a shearing stress
in the overlying sediments which may find relief in enrchelon
folding and faulting.. The folds and faults in the sediments would be oriented approximately at right angles to each other. The movements, structures, and their relationships are illustrated
in a and b of rigure 2. Assuming that the lower paleozoic beds had been deposited before the horizontal displacement occurred, then the younger formations would be deposited over these folds and assume the general pattern of the structures in the older rocks. Through differential compaction and sedimentation, this might well have smoothed out considerably the 900 relationship of the folds to the faults in the older Paleozoic rocks. ee part c, rigure 2. This theory would also account for the 23. Ff9r 2.
Q..
'Vf if mmmm 0O r.r.i...... 62 mmmmwmmm 6.
<24o i
S r / ..
Diagram of the Origin of the otructure 24.
greater dip to the southwest of the Mt. Pleasant structures inasmuch as both the dip of the folds and throw of faults
combine in this direction.
Production
The Porter field had produced over 10,000,000 barrels of oil at the close of 1934, and had become the
leading producing field in Michigan. The total production would have been considerably more if proration had not been
in effect. The discovery well, drilled in December 1931, was the only well until rebruary 1932. The steady increase in the
number of wells per month is shown in rigure 3. from the time
intensive drilling was begun, the production has increased steadily.
This steady rise is shown by the graph, rigure 3. The statistics
for the first part of 1935 were not available, but the output of oil has probably continued to increase due to a more liberal proration allowance. The average production per well has been
over 30,000 barrels. Acid treatment: The use of hydrochloric acid has
played a major role in the development of the fields in Michigan.
The Dow Chemical Company developed this acid, using corrosion
resistant inhibitors to protect the tubing and casing. before
acid treatment was developed, the rate of production was checked quite rapidly by the "salting up" of the pore space in the 'pay."
The amount of acid used in a well varies from 500 to 1000 gallons. This acid is pumped into the producing formation under considerable pressure, forcing it into the pore spaces and 25.0 ri gur e III
______I ______I I I
. ..+ . --- 4----,-- C) j...i O A - .
pp7. N
0 o . O4 o 0 S *3 6N 0 -0 i
0S4
.4 I 4 ...... 4 i\ 1U K -
1-.1.
11 t j.* ------4 .
'- -.-...-- -
110
~-II .-
0 0 0 8 0 0 0 0 8 0 0 0 0 8 o 0 0 0 0 0 o 0 0 o 0 0 0 0 0 8 0 0 o% 0 o 0 0 0 0 0 0 0 0 0 0~ 10 r-4 0l .-4 26.
away from the bottom of the well. The treatment has caused many wells to double and some to quadruple their output. A few have done even better than this. Praetidally all of the wells in the field have been or will be treated once, and some of them several times.
Properties of the oil: The oil produced in this area is a high gravity (A.P.I. 43 plus) paraffin base crude. There is a small amount of sulphur present but with present methods of refining this is not objectionable. The gasoline recovery is around 335%.
Future of the field: The length of time that the Porter pool will be productive depends on future drilling:to completely define the structure and producing area. At present, several areas should be productive especially to the northwest towards the Yost pool, and also to the southeast. everal large companies have a corner on the leases in these areas and are not developing them any faster than compelled to. The area to the southeast is structurally as high as the main pool, but it has not yet been definitely found to have any closure. iruture development in the acid treatment may also extend the life of the field and increase the ultimate production. 1 UNIVERSITY OF MICHIGAN i ID l 6illil HllI 3 9015 00326 7500
-4
". PLATE I c_ S _
$8,6, p, +
N N JASPER TWP. PORTER S TWP N N - 0 -% MIDLAND CO. 31I N 7 N MIDLAND CO. jN N i / OF!d.. f 64 >,R-2-W \ ' R -1-W 6i rm I
- , __ \_ _f___ _ _ N ____
10,N ,
.1 NNN
\ i\ '\ -\
530 NIItN -0- N \
%4.ft.00.4 0l 540 1 ~'
I NI op
N%.0001 __
46'e
Z. -a - 830 ' ' 6 _. . ~ r _ -l Z HJ = -
-, J 'i " 590 - ogd
1 16 * * 16 0 1 1 0 I/ \ \ %N 1 1 ' 11 0 - I j L ..... _. i i i 1 ) i j i .k P.- t -0 4- %--4-4 U 0 4h-T i i1 - A - i # A. # \19 l IS i j I ~J. - 0 -%'" 1 9ItI I' Am 0 14 MAP OF "THE P R E -J L POOL M60 S E 01OF THE CENTRAL MICHIGAN AREA
4.0I0, ."4N BY J. B.MAEBIUS
SUBSURFACE STRUCTURAL CONTOURS DRAWN ON THE TOP OF LOWER MARSHALL (RED ROCK) FORMATION N \\i1 N \ N
SCALE N N 4 i MILE " FW/9646
DATUM MEAN SEA LEVEL Nr \ N1ff___ "\i CONTOUR INTERVAL /D FEET
EXPLANATION BASE MAP PREPARED BY " OIL WELL THE MICHIGAN DEPT. OF 4 DRY HOLE CONSERVATION, GEOLOGICAL 0 BRINE WELL DIVI SION ___CONTOURS DEFINITE -~ CONT OURS INDEFINITE
R+W -- J". PSATE iT 351 4 0 0 ~NJASPER TWR PORTER TWP. MIDLAND _ CO. N MIDLAND CO. R-I-W I- at2-WN o 0.
1lP
?130
2160 / NN
218/ _ _ ___
// // ,, 1N
_22/ / ~Ny -V / r
-- /
'or M-40P N 1 -/- dor Il 00, 0 00- 1 a \ 1 1 a .0 -d
O~ft, 1 a-3\-r h z N ~..N\ i\'\N%. rb -W- -,*O Sn aa jeft J"a&I F- 'a - -7' ir T ' i- I 001ff #06" t : +i+4N 1 +-LW.0 -a to ______]11 __ 4 __ I lhI\\~\I ids' erg ago a -pa--- dpL-
a19 &so& Jeff i ' N N N N "'so
. , N t 4r N " %16 qfNw 2 4 / MAP OF THE NI ... %~J-~a a.Ole 1 ______Zvi_ 'aN~a ~1 1 or-~ . ers ~7 N N1% POTR N No Zvi y'a JSE 1LPOOF THE CENTRAL MICHIGAN AREA
BY J.B.MAEBIUS
SUBSURFACE STRUCTURAL CONTOURS DRAWN ON THE TOP OF TRAVERSE FORMATION
SCALE 'N NNNN \ \ o & JA /A///ir \\
DATUM MEAN SEA LEVEL * °p 1'. ' rwO i+ N °'a i p it CONTOUR INTERVAL /0 FEET
'aC4\Na - N\' NO N EXPLANATION BASE MAP PREPARED BY * OIL WELL THE MICHIGAN DEPT. OF 4. DRY HOLE CONSERVATION, GEOLOGICAL __ _r ( _ CONTOURS DEFINITE DIVISION r....VCONTOURS INDEFINITE
1 RIW + - __ PLA7T lII
I
" Xyo JASPER ~ TWP.* PORTER TWP 5 ? go M IDLANt -4CO. MIDLAND CO. 0 *0 0 R-"- AWto -xi2-
\ \
4,00 ____ N NNz%,.
00,,
4 No \\ \\
1\ '
Z LmKLJIILIXi_ M'
* t oI'
*V0 " i
S* S J " N \I \ N Jac 460 * r s Nr V / 1#4 a- /
1l k i f I S .. . ,"r all, _.t~ . .. o / /% II .
N N\ +" ON N*{ i",*, *~nJnJ " N \\, Nf\N \ \\J~ f 1 \ a"t " ?r. aJa ' "" Jr . , / ( \\ 27t
BY . B .ABIN
DR APNO THE NOP OF \ DUNDEFORATIO \ \ \ \ O r N\4 4270
SCALE 44 MLE n.ibc D ATUM 271 MEAN SEA LEVEL
CONTOUR INERVAL L /O FEETr
EXPLANATION NN NmNNN BASE MAP PREPARED BY N N * OIL welL THE MICHIGAN DEPT. OF 4 DRY HOL E a' 'aNR +W CONSERVATION, GEOLOGICAL 0--o CON TOURS DEPI/PVITE DIVISION IL --- CONTOURS /NDEF/IOWE I
PORTER TWP. - MIDLAND CO. PL ATE IY SEC 4 SEC 9 SEC /6 SEC SEC 28 SEC 33 T 2/
I
BELOW SEA LEVEL 450 450
-475 1910 -475 4
1659
1658 1691 -500 rs 5 166 1811 500
1822
ERS. -525 525 MIT PER R ,, R STATE OF
1 P -550 1527' 550
-575 I--. 575
08
-600 600
12675 2675 roP 0 C
-2700 Q 2700- / gt o, fHv -2725 272534 YI t I Y 4"0 7o. 7:0± r 0+. 2750 2750~
rONorF 2775 NORTH -SOUTH 2775 7:. SECTION A-A ACROSS PORTER 01I L FI ELD ~2800 SHOWING 2800' THICKNESS OF THE RED ROCK AND0 TOP OF THE -2825 DUNDEE AND PAY HOFtIZON 2623
HORIZONTAL SCALE
-2850 0 VIa ~, MILE 2e d VERTICAL SCALE T:. TOD 0 is3% tjoo FEET -2875 BY J.B. MAEB1 US 2875-
m
U NEUMMMEW
J /
y - ,\
. '
i
.- ,'"
y URARY Naeblus The sorter oil field . A1935.0
TA.